Talk:Infrared/Archive 1

General Comment

The definition of infrared in the opening paragraphs is inconsistent with the text. Authoritative sources (e.g. the McGraw-Hill Dictionary of Scientific and Technical Terms say and the IEEE standard dictionary) define IR as extending down (in frequency) to 1mm or 1000 micrometers.

In terms of overall organization of the article, it would be better to either break some of the subtopics out into their own articles, or at least organize the materials so that it is a bit clearer that the various alternative categorizations of the IR spectrum are not different definitions for IR, but application-specific designations of bands within the broader IR spectrum.

an improvement of the article could be, to add how this can be related to milling and sieving in the chemistry industry and how it might help with these different products of cell culture media. This would give a much wider state of mind on the subject at hand. — Preceding unsigned comment added by 78.147.19.99 (talk) 16:57, 1 December 2014 (UTC)

(An aside, the last comment regarding the orders of magnitude question under "How does this make sense?" below, has it right.) —Preceding unsigned comment added by Neolute (talk • contribs) 15:34, 7 May 2009 (UTC)

Wavelength of Humans wrong?

The wavelength of 12 µm in the sentence "Humans at normal body temperature radiate chiefly at wavelengths around 12μm (micrometers), as shown by Wien's displacement law." is wrong!
Reasoning:
1. The Wien's displacement law article reads "Mammals at roughly 300 K emit peak radiation at 3 thousand μm K / 300 K = 10 μm".
2. My own calculations give at 37°C = 310,15 K give 9,34 µm.
Or did I forget something????
Michilans (talk) 15:40, 5 July 2010 (UTC)

Miscellaneous

"IF your computer monitor is warm, the following patch should be coloured infrared"

I like this joke a lot :-D. But technically, all objects above absolute zero radiate infrared, right?

I imagine if something gets cold enough its black body spectrum will have very little infrared in it, with the peak dropping down into the frequencies below infrared. There will still be infrared emission, but I'm not sure if the swatch could be termed to be colored infrared at that point. Maybe it would be colored microwave.

considering that no one can "see" infrared, it seems weird to say that it is colored as such. if the combination of colors creates other colors, then the square can't be "colored" infrared because it would then be a combination. if you say that it just emits or reflects infrared, then the color is still meaningless, because any visible color could do that if it contains IR reflective qualities. and, black would both emit and absorb IR since it absorbs, and it gets hot.

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Who wrote that about sunburn? are you sure? "Although relatively harmless, overexposure to IR can cause damage to cells and is the cause of sunburn (despite ultraviolet commonly being thought of as the culprit.)"

Scientific American seems to diagree: http://www.sciam.com/askexpert/medicine/medicine57/ --rmhermen

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How does the infrared in remote controls work? How does our sensation of radiated heat work? Does our skin sense infra-red, or does it heat up because of it and we then sense the heat (are the two different?) -- Tarquin 16:47 7 Jun 2003 (UTC)

I put in a few sentences about remote controls. As for skin, it senses heat, not radiation directly. There is a difference. Direct radiation sensing, as happens in the eye, is a photochemical process caused by photons colliding with light-sensitive (and, if you're a cat, IR-sensitive) molecules. These molecules are highly selective about what wavelength of photon they respond to, which is why we can see in colour. Heat receptors in the skin are different. It seems that nobody knows how they work, but they just sense temperature in the bulk of the skin. This temperature is mediated by mechanical vibrations of atoms, not by radiation. The skin receptors don't know if the heat got there by IR radiation, or by conduction from a hot object. By the way, some snakes can see infra-red, too, but they do it in a different way from mammals with IR-sensitive eyes. Their IR sensors, called pits, are separate from their eyes. The pits detect IR by its heating effect on the skin inside the pit. They can work out which part of the pit is hottest, and therefore roughly where the hot object is. -- Heron

thanks! The above is probably enough to make a start on Thermoception. -- Tarquin 19:45 7 Jun 2003 (UTC)

I find it cool how the Military has grasped this technology to make infrared goggles. —Preceding unsigned comment added by 216.227.15.93 (talk) 12:57, 14 May 2010 (UTC)

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The page happens to be in 4 (possibly 5) different categories that mean the same thing. This wiki definitely needs to merge categories to lower their numbers.

Infrared as a color - physical significance?

Do you have any way to modify the human eye so that we can see infrared as a color?? This should be known by 2100.

Our retina's red-sensing cones are far more sensitive to long wavelengths. The green and blue cones aren't going to give much of a signal. See http://www.4colorvision.com/files/photopiceffic.htm . So, if we view some light which is well above 700nM wavelength ...and if that light is so bright that it does become visible, then it will appear to be deep red in color. This is different than with some digital cameras which "see" infrared as orange or even turquoise color. The three RGB (CYM?) filters on the camera CCD may pass differing amounts of NIR, and if the blue filter passes more NIR than the red filter, the camera will see NIR light as being bluish. --Wjbeaty 19:23, 28 May 2006 (UTC)

It should? omigosh I better get to work then! WTF?!--Deglr6328 16:31, 16 Aug 2004 (UTC)

http://www.amasci.com/amateur/irgoggl.html Yes, and for $10.00. --Alexander

Even for less, just take a IR-fluorescence card for €0.10.--BoP 07:44:59, 2005-09-09 (UTC)

One of the historical discoveries was that the IR radiation boundaries had no physical significance, but was arbitrarily placed due to physiology. Where should I place that in the article? History?--Rayc 03:03, 9 September 2005 (UTC)

Can you give me a hint which physical properties have "physical significance" in current setting of wavelength regions? Today IR is subdivided mainly by the detector range, the transmission windows in an optical fibre and the sources available. Think of Terahertz radiation, some years ago this region was just an uninteresting subportion of IR-or mm-waves. What is the "physical significance" you want to mention? --BoP 07:44:59, 2005-09-09 (UTC)

Not everoyne is physically the same, some people are more sensitive to IR than others71.58.198.190 (talk) 04:40, 17 May 2011 (UTC)

Applications

I think the article is good so far. One of the things I missed in it was Remote sensing. In a Remote Sensing grad class I took several years ago we focused on biomass and plant stress measurements from the Landsat program images, high Near-IR reflectance for healthy plants. A good discussion of this can be found in http://rst.gsfc.nasa.gov/Sect3/Sect3_1.html

Another simplistic sensing use I saw in a documentary was imaging polar ice to find polar bears, ice reflects IR and polar bears absorb IR (not sure of the band likely near-IR from the images shown). Boris58 22:54, 27 September 2006 (UTC)

How about gaming applications, for example the Wii? This is also creating interest in homebrew hacks on the wiimote such as Johnny Chung Lee's Wii projects Zlog (talk) 12:44, 20 January 2008 (UTC)

As well as gaming applications, some mobile phones also use infrared, although Bluetooth is used mainly. Wikiert (talk) 18:07, 23 October 2008 (UTC)

There is a less popular application that the use of infrared heat is utilized. The asphalt industry used infrared machines to heat asphalt in place to repair and decorate areas. This is a industry that is becoming more popular by the day because of its respect to "green". This application of infrared technology has been in use since the 1970's. --Colinkeinath (talk) 21:09, 28 October 2009 (UTC)

Fahrenheit and Celsius scales

The image only has a Fahrenheit scale. Does anybody know how to add a Celsius scale to it? Bobblewik  (talk) 12:16, 10 Oct 2004 (UTC)

Done. --Heron 09:37, 12 Nov 2004 (UTC)

what danger can infrared cause?

It's non-ionising, so the only danger is due to heating. In other words, if it's powerful enough, it will burn your skin. --Heron 09:08, 12 Nov 2004 (UTC)

This is only true in a certain range of pulse lengths and intensities. There are several effects involved at higher intensities (like these found in lasers), like multiphoton processes, plasma generation and such. But in the low intensity case the heating effect is the dominant. --BoP 11:44, 2 Jan 2005 (UTC)

Besides the heating also electrical effects might influence particles at the resonant frequencies, this is where the particle has about the size of the radiation. Which is neglible for humans in the range below 2mm radiation. However cm long waves have shown that they can affect the hair of certain animals... --BoP 07:44:59, 2005-09-09 (UTC)

Related to the dangers of IR, in the "Different Regions in the Infrared" section, there is a mention that the 1530-1560 nm range is mainly used for long-range telecommunications. I've heard that this range is considered the "eye-safe" range. See here for a definition of "eye-safe". In general, I think the information in the previous link and this one from the same website explain some useful but simple ideas that could be incorporated into the article (if not already) such as why near-infrared light is able to permanently damage eyes, and 1.4+ micron light doesn't. This sort of gives context to why you shouldn't ever point a "laser" at someone's eyes. Or maybe just add a reference somewhere to the wiki article for laser safety, although ideally I think it should be the other way around. Kzero22 (talk) 19:19, 7 July 2010 (UTC)

15 micron band saturation and the greenhouse gas effect

I am doing some research on the question of the carbon dioxide greenhouse effect. Specifically, some critics of Global Warming claim that the 15 micron band is "optically saturated" for CO2 in the atmosphere. Further increases in CO2 will not have the expected effect, they argue, since the band cannot absorb anymore. There just ain't more 15 micron IR left to absorb. We would appreciate any info you could provide on this question. Specifically, how does the IPCC model IR saturation in the 15 micron band for the climate change predictions?

The center of the 15 micron band is saturated, but increasing CO2 concentration extends the unsaturated wings of the band, thus absorbing more IR radiation with increasing CO2 concentration. [1] treats this in some detail. The author there states that you can *still* increase the greenhouse effect by adding CO2 to the atmosphere if the CO2 level is 10 000 times higher than our CO2 level (3 atmospheres). Wikisteff (talk) 22:38, 12 November 2009 (UTC)

IR is not "Heat radiation"

The article and discussion here seems to reflect a common misconception about IR that I'd like to clear up. Basically, IR does not equal heat, "heat radiation", etc. Warm/hot objects radiate many wavelengths of electromagnetic radiation ("light"), INCLUDING infrared. Have you ever seen something extremely hot glow red? Or get hotter and glow orange, then yellow, then white? Same phenomenon.It glows IR first, you just can't see it. As for transmission of heat via IR, well yeah. Absorption of any wavelength of "light" warms things, INCLUDING infrared. Um, that's all. Thanks.

• EDIT*

After adding this comment, I went to clarify the article, and realized that this misconception /wasn't/ reflected in it after all. But in that case, what prompted me to post this and "fix" it? Twilight zone...

The article could be less wishy-washy if it clearly states that infrared "heat radiation" idea is simply wrong. After all, a snowbank puts out mostly microwave for its blackbody spectrum. And a 1000mW laser pointer can burn holes in objects. The IR/heat connection is a widespread misconception that's mostly supported by children's science books. But since we were all children at the start, even some physicists end up believing that IR is "heat radiation." One person who has written about this misconception is the physicist Dr. Chris Bohren, but I don't think his article is online anywhere. See his book on popular science, "Clouds in a glass of beer." --Wjbeaty 19:15, 28 May 2006 (UTC)

There still seems to be something missing in the article on the "heat" topic, it states that "IR light from the sun only accounts for 50% of the heating of the Earth, the rest is caused by visible light." Doesn't some of the heat on the earth come from other forms of electromagnetic radiation from the sun other than visible light? Or is the absorbtion rate for other non-visible electromagnetic waves that the sun produce just too low to count? This should be clarified, since the article also stated that "Light or electromagnetic waves of any frequency will heat surfaces which absorb it." --Tetrakatus 27 June 2006

Other heat-adding or heat-cooling mechanisms include:

* radioactive decay (adds heat);

* electromagnetic energy (adds heat);

* volcanic activity (chills surface, heats atmosphere)[1];

* solar wind (adds insignificantly)[2];

* lunar tidal heating (may influence additional volcanic activity)[3]; and

* greenhouse gases (traps heat).

[1] A. Robock, Volcanic Eruptions and Climate (2000)

[2] B. E. Wood, Astrospheres and Solar-like Stellar Winds (2004)

[3] J. G. Williams et. al, Lunar Power Dissipated by Tides and Core-Mantle Interaction (2000)

Hope that helps.

--User:Thangalin 23 September 2006

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Excuse me, I think this sentence in the Apps->Night-vision paragraph is a bit screwed up, could some native speaker take a look at it...? (you can delete this post afterwards) [bkil] 17:12, 11 July 2005 (UTC)

Smoke is more transparent to infrared than to visible light, so fire fighters use infrared imaging equipment when working in smoke-filled areas because it does not interfere with other devices in adjoining rooms - this is especially important in areas of high population density (IR does not penetrate walls).

I believe that a partial sentence describing indoor infrared comms got nixed with one on infrared firefighting equipment. Fixed it. Jaraalbe 20:27, 11 July 2005 (UTC)

Yup, just as I suspected! ;) Tx for your edit! :) 62.201.113.195 21:34, 11 July 2005 (UTC)

Didn't a Canadian, P. M. S. Blackett (poor guy, with those initials!) do research on infrared in WW2? --squadfifteen

The whole article is screwy. IR is not 'light', by definition. I can't take seriously anyone who claims to be talking about physics and then refers to 'infrared light'. — Preceding unsigned comment added by 92.14.30.2 (talk) 23:04, 5 March 2012 (UTC)

Lower boundary of IR

I've tweaked the article a bit, since there seems to be no strong definition I can find of the exact boundary between visible and IR (I've seen 700nm, 750 nm, 760 nm, 780nm, and 800nm listed in various references and standards.) I've also added a paragraph addressing the issue. --Bob Mellish 18:10, 15 December 2005 (UTC)

Authors who give various IR boundaries just show that they don't understand how retinas behave. Since human retinas have no sharp frequency cutoff, therefore there can be no sharp boundary between IR and visible red light. Here's a good article on retinal response: http://www.4colorvision.com/files/photopiceffic.htm

On the other hand, for almost all practical purposes, 700nM is the boundary between IR and visible light. Our retinas are about 10,000 times less sensitive at 700nM than at the peak at 550nM (the green frequencies.) For scenes illuminated with broadband white light sources, the wavelengths above 700nM have far less than 1% contribution to visible red colors, and are essentially invisible. However, if the intensity of a 700nM narrowband source is cranked up by 10,000 times, it becomes just as visible as green light. Similar things are true of ALL near-infrared wavelengths: to easily see 750nM, turn up the brightness by about 200,000X. To easily see 800nM, turn up the brightness by about 10^7. The lower boundary of IR wavelenghts depends on the brightness and frequency distribution of the light source used as illumination. --Wjbeaty 19:15, 28 May 2006 (UTC)

One important note is that the visual system is stimulated by sources as a power law (see Stevens' power law for reference) with a coefficient between 0.33 and 0.5, depending on the source. That means that being 10 000 times less sensitive in photometric terms corresponds to between 20 and 100 times less sensitive in perceptual terms, which is not an insignificant difference. If one were looking at a monochromatic source in a dark room at 710 nm, one's eyes would certainly adapt to be able to see it as a dim red. You can easily test this by turning on an element on your stove to medium at night, if you have a dark kitchen. Not that I disagree with Wjbeaty, who seems to have it right. However, the lower cutoff adopted for IR matters a lot for the power contained in the infrared. Using 750 nm, the irradiance at the Earth's surface is 32 W/m² in UV, 503 W/m² in the visible, and 468 W/m² in IR. Using 700 nm as a cutoff, the irradiance at the surface is 32 W/m² in UV, 445 W/m² in the visible, and 527 W/m² in the IR. Wikisteff (talk) 22:45, 12 November 2009 (UTC)

Could it be that increasing the intensity is not making the the longer wavelengths more visible but the "red" that is perceived is the result of the natural harmonics present that are at unperceptible levels for lower intensities?Carywt64 (talk) 12:29, 13 October 2009 (UTC)

To Carywt64, received light has essentially no higher harmonics at normally-encountered intensities, as the energy densities required for nonlinear optical effects in most materials can only be found in very high-powered lasers. So it's a real effect of wavelength. Wikisteff (talk) 22:45, 12 November 2009 (UTC)

So what is our consensus for the boundary wavelength? I will request 700nm. But I see that some one changed it today to 740nm. Graeme Bartlett (talk) 12:04, 7 July 2011 (UTC)

Ahooo

Riiight, it's a wolf. This dangerous animal can be seen at http://coolcosmos.ipac.caltech.edu/image_galleries/ir_zoo/dog.html --Femto 14:20, 6 April 2006 (UTC)

Cellphones

Can someone add the use of infrared on cellphones. --MarioV 01:05, 1 August 2006 (UTC)

Ice cubes emitting microwave?

and ice cubes emit mostly microwaves...

It doesn't match. If microwaves start at 1 mm, according to Wien's displacement law the top wavelength should be about 2.9 K! Sure water is frozen at that temperature, but it is not what I mean with just ice cube. --Pinzo 19:49, 4 October 2006 (UTC)

CADPAT

The Canadian Army uses a type of camouflage called CADPAT that reportedly reduces or conceals IR. Think this should be included?

--JodoYodo

Different regions in the infrared

This section is lacking in any references and so it is unclear who is using the listed "schemes" or how they are applicable. I have no idea how this information was derived. It could be complete rubbish for all I know. Should the first two "schemes" be scrapped? Thanks. — RJH (talk) 18:55, 3 April 2007 (UTC)

Citations

Why are there so many sections in this article that are missing citation? --the_hoodie 17:21, 23 May 2007 (UTC)

The fact "Humans at normal body temperature radiate chiefly at wavelengths around 10μm" cites a page that does not contain that information

That was boned by this anon IP edit in Dec. 2008. I'll take it out. Dicklyon (talk) 15:17, 26 October 2009 (UTC)

The link at reference [18] is to a business information site which requires an account. This doesn't seem like a legitimate reference, and could be construed as a company marketing there business research service. — Preceding unsigned comment added by 70.194.1.65 (talk) 16:24, 31 August 2012 (UTC)

Missiles

homing on to the IR signature of the target aircraft, typically the jet engine exhaust plume.

My understanding was this is NOT true; IR missiles home in on the hot metal of the tailpipe, not on the gases themselves which are too diffuse to track. But then this is old information and I know IR seeker heads have changed since then. The sources I can Google talk about both hot metal and exhaust plumes, but they're not all that great ( a lot are corporations with a product to sell ) so I would hope somebody has a good book they can check.

Eleland 20:07, 25 June 2007 (UTC)

therapeutic uses

This documents a new one, but there are other, better known therapeutic uses such as for cramps etc. --Espoo 18:08, 27 June 2007 (UTC)

"FIR is also gaining popularity as a safe method of natural health care & physiotherapy. Far infrared thermometric therapy garments use thermal technology to provide compressive support and healing warmth to assist symptom control for arthritis, injury & pain."

The above reads like it came straight from an info-mmercial. Before you know it someone will add some BS about the "benefits" of embedded amethyst crystals in your clothes, or something equally asinine. The marketing jargon should be dropped and simply something to the effect of "insulating garments and wraps can increase blood flow to the extremities, perhaps relieving pain and accelerating healing." Ideally, a legit source should be provided to justify the claim. Also, "compressive support" is completely unrelated to an insulating clothing item, which may or may not be compressive. 143.215.217.47 (talk) 18:37, 13 April 2010 (UTC)

There are few businesses which are selling products on FIR. Here is one such company. Their claims are moderate. Yndesai (talk) —Preceding undated comment added 10:16, 6 May 2012 (UTC).

IR Blaster / IR Blast Diode

Should something be added about an IR Blaster or IR Blast Diode used to actually create the IR signal?166.20.114.10 15:49, 6 July 2007 (UTC)

Night Vision

Added a couple of references resolving some year old tags. Rewrote the Night Vision section as it was confusing night vision which deals with infrared light and thermal imaging which deals with infrared radiation. Arcos9000 04:36, 13 August 2007 (UTC)

Thermography copyright violation

In November 2006, user 70.91.43.253 replaced the entire Thermography section of the article with text copied from http://www.infraspection.com/FAQ.html. (Here's a link from archive.org, showing that they had the text before it was added to Wikipedia.) I've reverted the section to the previous version.  --mconst 01:16, 2 November 2007 (UTC)

Wavenumbers

Can we add wavenumbers (cm-1) into this article. They are an extremely common way of measuring infrared frequencies

what is the history of infrared rays? KALIY Smith —Preceding unsigned comment added by 75.49.37.47 (talk) 00:48, 20 March 2008 (UTC)

Heat - Infrared - The resulting frequencies from external stimuli

I have been wondering for years: There are apperantly infinate frequencies for an object to be stimulated with/by. However, I wonder if the heat generated, due to the stimulation, is part of the reaction of the object limited to the infrared range? David Colley 75.0.13.223 (talk) 16:54, 22 March 2008 (UTC)

No.

How does this make sense?

Towards the beginning of the article it says: "Infrared radiation has wavelengths between about 750 nm and 1 mm, spanning five orders of magnitude." How is 750-1000 five orders of magnitude? Isn't this only 1/4 of an order? Or is there some base other than 10 which is being referenced? Anyone? 65.183.135.231 (talk) 19:03, 19 May 2008 (UTC)

750 nm is 0.75 μm and 1 mm is 1000 μm. Seems like 3 orders of magnitude to me. Thunderbird2 (talk) 19:06, 19 May 2008 (UTC)

Doh!65.183.135.231 (talk) 19:20, 19 May 2008 (UTC)

History cruft

The history cruft was added by a drive-by anon here; since we don't have anyone we can ask about sources, I recommend we just flush the unsourced stuff. OK? Dicklyon (talk) 19:02, 18 December 2008 (UTC)

Candela for sunlight

It is strange to mention the candela value of bright sunlight in relation to how much of the sun's energy that reaches earth's surface is IR. Candela is a unit weighted for the perception of humans, so all IR light will have an irradiance of 0 candela, no matter how bright. "Bright sunlight provides luminance of approximately 100,000 candela per square meter at the Earth's surface." I would instead use the total radiant flux of the sun across all wavelengths.

122.161.6.100 (talk) 11:05, 23 August 2009 (UTC)

Hey, I just fixed the candela and lumens per Watt to be something more useful, along the lines of your initial comment. Wikisteff (talk) 22:50, 12 November 2009 (UTC)

Article

Is the subject of this article supposed to be infrared, or infrared radiation? "Infrared" can imply something broader, such as interactions with matter, and "IR radiation" is more specific. Which is it? Tranh Nguyen (talk) 04:54, 15 October 2009 (UTC)

It appears to be infrared radiation, broadly construed, including applications. Dicklyon (talk) 04:56, 15 October 2009 (UTC)

So shouldn't the article be titled "Infrared Radiation"? The ambiguous "Infrared" as a title seems odd, and implies a wider discussion of heat, etc. Tranh Nguyen (talk) 05:02, 15 October 2009 (UTC)

I think the current title is fine. If there's some other infrared topic that needs to be distinguished, show us and we can consider what to do. Dicklyon (talk) 05:03, 15 October 2009 (UTC)

Be sure to cite your sources when you add information, so we can verify it or express it better to agree with the source. Dicklyon (talk) 06:49, 15 October 2009 (UTC)

Frequency values.

Infrared radiation is right at the intersection of two different schools of measurement: The first being the measurement of visible light (commonly measured by length), the second being the measurement of radio frequencies (commonly measured by frequency).

As a result, it's important to list the ranges of infrared using both wavelength and frequency. I've added frequency values in the lead section of the article. InternetMeme (talk) 11:36, 26 November 2009 (UTC)

Solar Irradiance

In Raymond S Bradley's book Paleoclimatology the figure of 342 wm^-2 but it is not broken down. The figure given in the article is 1kwm^-2 and is broken down. Can someone explain the difference between these two figures? Wilmot1 (talk) —Preceding undated comment added 10:16, 10 December 2009 (UTC).

Heat Seeking Telescope

The Times:-Dominic Dyer, chairman of CWI. “These animals are being wiped out by poachers who are increasingly well equipped with automatic weapons, GPS satellites, night-vision kit and heat-seeking telescopes to spot animals at night."

Do these heat seeking telescopes home in on the animals and automatically control the positioning of the telescopes to track them? Isn't this how the Spitzer Space Telescope works? Kwenchin (talk) 01:53, 21 March 2010 (UTC)

I think the source quoted in this Wikipedia entry only refers to latitudes similar to the US average latitude. — Preceding unsigned comment added by 81.178.192.32 (talk) 18:23, 22 October 2012 (UTC)

"Infrared filters" copyright violation

The section "Infrared filters", added in October 2007 by user USNV, seems to be mostly copied from the U.S. Night Vision website. (That site has changed in the meantime; the link is from archive.org, showing that the site had the text before it was added to Wikipedia.)

It's not an exact copy -- several words have been changed, and there's one original sentence, but the majority of the text is identical. Even the idiosyncratic capitalization ("all Generations of night vision") has been preserved.

To be safe, I've removed the whole section, but please feel free to add back the original sentence if you think the article would be better that way.  --mconst (talk) 10:08, 26 July 2010 (UTC)

Is or was infrared ever called infared?

This is what I had thought until a while ago. I notice that "infared" redirects here. Also, the spelling without the "r" appears in the history section in 1945. —Preceding unsigned comment added by 78.151.214.93 (talk) 21:12, 29 November 2010 (UTC)

Just typos. Fixed. Dicklyon (talk) 21:51, 30 January 2011 (UTC)

Heat therapy

Infrared is a tool to apply heat therapy, that in some aspects is better that application by means of a hot vehicle, such as water, or water soaked supports. It seems that IR radiation penetrates more deep into the body. It seems that IR radiation produce vasodilation also. I have been submitted to it to treat pain in cervical and lumbar regions, in a rehabilitation medical facility, with very good results. In Spain, IR lamps are sold in pharmacies, I suppose it is also done universaly. So it surprises me not to find any reference to this application of IR radiation. Apart from my personal experience I do not have referenced sources to support these claims. Can any wikipedist help?--Auró (talk) 14:49, 30 January 2011 (UTC)

You can find books on heat therapy that mention infrared here. You could add a small section this article, with link to heat therapy, and add more there. Dicklyon (talk) 21:50, 30 January 2011 (UTC)

Tank you for your assistance. I have added a section in "Heat therapy" article, and added a link to it in this article. I plan also to make a new section in "Infrared heaters" article.Auró (talk) 18:32, 13 February 2011 (UTC)

infrared reflectography

Hello, there is a redirection link from infrared reflectography to infrared. There are dedicated articles in several other languages (fr/it/es), it may be better (?) to have a red-link to be filled with a dedicated article in English latter ? (Sorry for my English, I am French) v_atekor (talk) 11:47, 21 April 2013 (UTC)

Visibility

It would be nice to have a section (or subsection) on the visibility of near-infrared. A class 1 1064 nm Neodymium:YAG laser shined into dark-adapted eyes is clearly visible, although the upper limit of class 1 is way too much power for maximum color saturation. For peak saturation, you need an average value of 0.069 mW.

(By the way, I support 700 nm as the dividing line. "Visible light" is just a convenient (easy-to-remember) approximation of what most people can see reasonably well under most circumstances.)

Sources:

Relative Luminosity in the Extreme Red

• Goodeve, C.F. (1936). "Relative Luminosity in the Extreme Red". Proc. R. Soc. Lond. A. 155. London. doi:10.1098/rspa.1936.0127.

On the sensitivity of the eye to the infra-red limit

• Lau, E; Leo, W (1948). "Uber die Augenempfindlichkeit an der ultraroten Grenze". Annalen der Physik (in German). 437 (no 5-6): 242–255. doi:10.1002/andp.19484370503. {{cite journal}}: |issue= has extra text (help); Unknown parameter |trans_title= ignored (|trans-title= suggested) (help)

The Sensitivity of the Human Eye to Infra-Red Radiation

• Griffin, Donald R.; Hubbard, Ruth; Wald, George (1947). "The Sensitivity of the Human Eye to Infra-Red Radiation". Journal of the Optical Society of America. 37 (7): 546–553. doi:10.1364/JOSA.37.000546. {{cite journal}}: Unknown parameter |subscription= ignored (|url-access= suggested) (help)

Foveal Sensitivity of the Human Eye in the Near Infrared

• Walraven, P. L.; Leebeek, H. J. (1963). "Foveal Sensitivity of the Human Eye in the Near Infrared". Journal of the Optical Society of America. 53 (6): 765–766. doi:10.1364/JOSA.53.000765. PMID 13998626. {{cite journal}}: Unknown parameter |subscription= ignored (|url-access= suggested) (help)

Visual sensitivity of the eye to infrared laser radiation

• Sliney, David H.; Wangemann, Robert T.; Franks, James K.; Wolbarsht, Myron L. (1976). "Visual sensitivity of the eye to infrared laser radiation". Journal of the Optical Society of America. 66 (4): 339–341. doi:10.1364/JOSA.66.000339. The foveal sensitivity to several near-infrared laser wavelengths was measured. It was found that the eye could respond to radiation at wavelengths at least as far as 1064 nm. A continuous 1064 nm laser source appeared red, but a 1060 nm pulsed laser source appeared green, which suggests the presence of second harmonic generation in the retina. {{cite journal}}: Unknown parameter |subscription= ignored (|url-access= suggested) (help)

Absolute sensitivity of the eye in infra-red spectrum

• Pinegin, Nikolai Ivanovich (1945). "Absolute sensitivity of the eye in infra-red spectrum". Proceedings of the USSR Academy of Sciences (in Russian). 67. Moscow: Russian Academy of Sciences: 627–629.

Near infrared light absorption in the human eye media

• van den Berg, TJ; Spekreijse, H. (1997). "Near infrared light absorption in the human eye media". Vision Research. 37 (2). The Netherlands: The Netherlands Ophthalmic Research Institute, University of Amsterdam: 249–53. PMID 9068825.

Infrared color reversal

The colour of light of very long wavelength

• Brindley, Giles Skey (1955). "The colour of light of very long wavelength". The Journal of Physiology. 130: 34–35. PMID 1363450. {{cite journal}}: Unknown parameter |subscription= ignored (|url-access= suggested) (help)

Above 704 nm colors reverse and trend back towards orange. Color Vision: From Genes to Perception

Photoreceptor spectral sensitivities: common shape in the long-wavelength region Lamb, TD (1995). "Photoreceptor spectral sensitivities: common shape in the long-wavelength region". Vision Research. 35 (22): 3083–3091. doi:10.1016/0042-6989(95)00114-F. Absolute sensitivity of the eye in infra-red spectrum

Zyxwv99 (talk) 01:38, 14 October 2013 (UTC)

Fixes needed in "Sensor response division scheme"

"The onset of infrared is defined (according to different standards) at various values typically between 700 nm and 800 nm, but the boundary between visible and infrared light is not precisely defined. The human eye is markedly less sensitive to light above 700 nm wavelength, so longer wavelengths make insignificant contributions to scenes illuminated by common light sources. However, particularly intense near-IR light (e.g., from IR lasers, IR LED sources, or from bright daylight with the visible light removed by colored gels) can be detected up to approximately 780 nm, and will be perceived as red light. Sources providing wavelengths as long as 1050 nm can be seen as a dull red glow in intense sources, causing some difficulty in near-IR illumination of scenes in the dark (usually this practical problem is solved by indirect illumination). ..."

This paragraph has the following issues:

"between 700 nm and 800 nm" should be "between 680 nm and 800 nm"

"...but the boundary between visible and infrared light is not precisely defined." This is confusing two separate issues and OR. The thing that is getting confused is the literal meaning of "visible" with conventional definitions of "visible light." The boundary is very precisely defined by several different authorities, e.g., CIE, ISO, etc. These boundaries are conventional and don't agree with each other because in the real world the sensitivity of the human eye gradually tapers off.

"The human eye is markedly less sensitive to light above 700 nm wavelength, so longer wavelengths make insignificant contributions to scenes illuminated by common light sources." Nothing happens at 700 nm wavelength other than "visible light" ends by the most widely cited definition of "visible light." This statement could equally apply to 680 nm, 800 nm, or any wavelengths in between.

"...can be detected up to approximately 780 nm..." Nothing happens at 780 nm other than the CIE scotopic luminosity function ends at 780 nm, as does the abridged version of the CIE photopic luminosity function (unabridged ends at 830 nm). Once again, someone seems to be taking conventionalized definitions are reading too much into them. By this logic, the weather should suddenly get better on the first day of spring.

"Sources providing wavelengths as long as 1050 nm can be seen as a dull red glow in intense sources..." The only range of wavelengths I've ever heard of that always looks like a dull glow is about 290 nm - 305 nm. At 310 nm children and young adults still have some visual acuity. Below 290 nm people tend to see nothing. At 300 nm those who see anything at all tend to see only their own eye fluorescence, mainly lens fluorescence. No such problem occurs in the infrared, except with sources that are prone to producing dull glows. Furthermore, "red" is not necessarily correct either. Although 1050 nm usually looks red, it can also look white or any of several other colors depending on whether it is flickering or seen in peripheral vision.

Any finally, only the 1050 nm number is supported by the reference (for scotopic vision, 1000 nm for photopic). Everything else looks like OR. Zyxwv99 (talk) 14:12, 24 October 2013 (UTC)

Visible or invisible?

The first paragraph needs to sound less self-contradicting:

"Infrared (IR) is invisible radiant energy [...] although people can see infrared up to at least 1050 nm in experiments[2][3][4][5]".

Unless, of course, the experiments took place in the Twilight Zone. 5.12.167.196 (talk) 18:05, 2 August 2014 (UTC)

Actually it's not just in vision experiments. Nowadays huge numbers of people work with near-infrared lasers and can see the light. With broadband sources such as diodes you can't be sure what you're seeing because the dominant wavelength (perceived wavelength) can be a great distance from the peak wavelength. (To calculate dominant wavelength get the spectral curve with a digital spectrometer, slice it into 1 or 5nm slices, then adjust each slice for the sensitivity of the human eye at that wavelength, then find the midpoint of the area under the curve.) The two most common wavelengths of infrared laser pointers are 808nm and 980nm. The dot from a weak (5mW) 808nm is clearly visible at night in a dark room, even though the sensitivity of eye at that wavelength is only 1/2 millionth as great as at 555nm (wavelength of peak sensitivity). At 980nm it's only about 1/2 billionth, but you can still see the light when shined directly into the eye. (Not recommended, especially as many of the cheap ones sold on eBay for $15 are 2-20 times as powerful as advertized.) Millions of people own these lasers. The 980s are used in China for fake currency detection. Their visibility is common knowledge. Also, technicians who work with fiber optics routinely report seeing infrared in the low-mid 800s. The problem is that the visible portion of the near-infrared spectrum is less than 0.05% of the entire infrared spectrum, and is only visible from narrow-band sources such as lasers. That's makes the wording a bit tricky. Zyxwv99 (talk) 02:13, 3 August 2014 (UTC)

Confusing caption

The photo shows a terminal connection fitted to a silicon carbide element. The terminal appears to be hotter than the element, because its emissivity is lower. The terminal is made from a white ceramic.

Materials with higher emissivity appear to be hotter. In this thermal image, the ceramic cylinder appears to be hotter than its cubic container (made of silicon carbide), while in fact they have the same temperature.

I was completely confused by the original caption (left side) of this image— so I have rephrased it in a way that seems plausible to me (right side). I might have completely misunderstood the point, so please feel free to revert my edit and come up with a (hopefully) more sensible description. --Cheers, Rfassbind -talk 22:35, 3 January 2015 (UTC)

The Jan 2015 caption is better, but it ignores the possibility of the surroundings being warmer than the body, which they aren't in this case, but could be in the generalizing language of the caption. I will edit. --ChococatR (talk) 22:36, 15 May 2021 (UTC)

Upper wavelength boundary of IR

In the opening paragraph, the article states that the upper wavelength boundary of the IR spectrum is at 1 mm. However, the linked article in the reference ( http://www.crisp.nus.edu.sg/~research/tutorial/em.htm ) states that the upper wavelength for IR is 300 μm (0.3 mm). Which is correct? --Rogermw (talk) 14:09, 8 August 2015 (UTC)

Something wrong with the picture at the top of the page

Something is wrong with the picture at the top of the page, is not displayed. Ulflarsen (talk) 18:54, 15 March 2016 (UTC)

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Diagram of spectrum unclear

Existing diagram in article is "ElectromagneticSpectrum5.png" which seems very hard to read.

Electromagnetic spectrum with visible light highlighted

Instead could we use this ("EM spectrum.svg"-->)
with a different caption (eg "IR is between Visible Red and Microwave") ? - Rod57 (talk) 23:42, 1 December 2017 (UTC)

Reflected light photograph in various infrared spectra...

This image has issues. In particular, the middle photo is not solely of "Near IR (750-900 nm)" but instead is an image composed of near infrared AND visible light, a kind of image commonly made using digital cameras that have been modified by removing the infrared filter from the front of the imaging chip. As such, the blue and green channels are from visible light only, whereas the red channel is a composite of visible (red) and infrared. Most of the information in the central photo is not from the infrared. The SWIR image on the right does not have this problem, but makes comparing the two problematic. Ideally a different suite of photos, one where the near infrared image is taken with a filter on the lens that removes all visible light, would be used instead. However, I don't happen know of such a set that could be used, so I am leaving the original. — Preceding unsigned comment added by Barak Thunder (talk • contribs) 18:21, 20 April 2018 (UTC)

Definition of IR, long wavelength "limit"

As per my recent edit, I apologize if the text was "unreadable," but with all due respect the editor who reverted me could not possibly appreciate the magnitude of the inaccuracy reflected in the current wording and in the obsolete table I just deleted. To be clear: this has ONLY to do with symantics, not science. Above in the talk is a discussion of the short-wave limit (= visual response) to the tune of 5-10%. In the case of the long limit the discrepancy from common usage may be over 1000%!

I have colleagues who work with frequencies up to ~5GHz (60 μm) and they call it "Terahertz" (or in astronomical applications often "submillimeter", synonymous). And I know others call it far-IR or thermal IR. I know of no one who CURRENTLY calls 300 μm "IR". The reason for such a wide wavelength range historically being relegated to the term "IR" is that these were all wavelengths (except near-IR) that could hardly be detected or generated other than thermally. It was a "black hole" in the EM spectrum. Now that hole is being (has been) closed from both sides, and which side you were coming from (or which funding you're seeking!) might determine what you call it. A figure would be nice, and could show the short wavelength limit (700 is ok with me) but would HAVE to show the terms IR and THz (and also, microwave and THz) overlapping. Any attempt at further simplification, saying that 100um IS THz or IS IR, is going to be stepping on someone's foot. Calling 900um "IR" is just antiquated, no one does! If my prose is so hard to read, as it was according to the one who reverted me, then let a better writer tell the readers what I just said. And when this is settled, the similar error in the lede and elsewhere can be corrected. But please don't tell all the pioneering THz researchers that they should be calling their radiation "IR", they don't have to listen to you, nor should an attempt to "simplify" wikipedia lead to misleading readers by > 500%. Interferometrist (talk) 02:13, 6 January 2022 (UTC)

Lets take this a piece at a time, and please no mass deletions without consensus / based on your personal knowledge. Where does the article call 300 μm "IR"? I don't see it. North8000 (talk) 14:42, 6 January 2022 (UTC)

Struck my question. I mistakenly read your statement as 300 nanometers North8000 (talk) 15:50, 6 January 2022 (UTC)

I think his rationale is that Terahertz radiation (1mm to 100μm) is no longer generally considered part of the infrared band. 300 μm is in the middle of that band and is also within the table's definition of IR since that starts at 1mm. I agree sources are needed, but since there is no formal or official definition for the IR band this is always going to be a bit fuzzy. Our Terahertz radiation article states that it can be considered part of the microwave band or the infrared band. This 2010 book seems to agree in its note about terminology, but in later chapters clearly differentiates Terahertz and infrared as two different things.

I don't think deleting the table is the answer here, but a note is needed that it is increasingly popular to put 0.1–1mm in the microwave band rather than infrared. Or otherwise indicate that there are different arbitrary boundaries. SpinningSpark 15:16, 6 January 2022 (UTC)

5GHz is not 60μm. Did you mean 500GHz? SpinningSpark 15:19, 6 January 2022 (UTC)

@North8000: Well it says that IR goes as long as 1mm which is 1000μm, and I'm saying that even 300μm is no longer referred to as IR (except in outdated tables like that one, but not in any paper where they are working at that 1THz = 300um), so the table clearly does NOT reflect current usage. And this is not a "mass deletion" it is the deletion of a single table which is substantially wrong. Last time I checked, information in wikipedia articles which is known to be wrong, should be removed. If you REQUEST then I could come up with a similar table but it would also be inaccurate especially at the (here we go again....) "boundary" between vacuum UV and soft x-rays. So my table would show those names as having large overlaps and it wouldn't be by an expert with respect to each "boundary" and if it were to be properly sourced then I would need to (which I don't have time for) find a citation for each row of the table, and even then it would be easy (especially if older sources were admitted) for someone to find an equally RS which cites different numbers. And SpinningSpark mentioning a 2010 book shows that he/she is already looking at information that is substantially out of date just given advances in THz technology over the last 12 years.

If the point of the section is to delineate where IR lies within the broader EM spectrum, then I would propose simple (but sufficient!) wording such as:

IR refers to the region of the EM spectrum in between visible wavelengths and Terahertz/submillimeter wavelengths, with the latter boundary not well-defined. PERIOD

If it's not well defined, then the table can't be wrong. Where are the sources that say terahertz should definitely not be classed as infrared? Until that starts to work through to published sources, Wikipedia will continue to reflect what is actually out there now. It does not matter that attitudes in the field has changed or is changing if that is not yet reflected in published books. Your position that we are posting wrong information that needs instant deleting is just over the top. SpinningSpark 16:31, 6 January 2022 (UTC)

@SpinningSpark: Sorry, I meant 5THz, a typo. But as I said, I go to talks where 60 μm but always called 5THz (there are quantum-cascade lasers operating near that frequency) is treated as "Terahertz". But it can also be called IR! That is why ANY table that only has non-overlapping boundaries has to be wrong according to current usage. And that is why my EARLIER edit that was reverted DID try to point out that the table was misleading in that respect. But deleting the entire table in order to replace by a more current one (or the above simple sentence) is what I need to get any attention around here. My new edit removes incorrect information from wikipedia, demanding a change in wording (which I already tried!) that I'll leave to someone else. I have better things to do with my time than editing new content that gets reverted and I consider the time I'm taking to type this rather wasted, but hope it will be explanatory to at least two editors involved. Interferometrist (talk) 15:55, 6 January 2022 (UTC)

Your "IR refers to the region of the EM spectrum in between visible wavelengths and Terahertz/submillimeter wavelengths, with the latter boundary not well-defined." looks good to me. North8000 (talk) 15:58, 6 January 2022 (UTC)

@Interferometrist: Instead of you warring / violating policy redoing contested mass deletions based on personal knowledge, let's work something out here. What do you propose? North8000 (talk) 16:03, 6 January 2022 (UTC)

Maybe I'd propose that I be treated with more respect, because this is the kind of shit that makes me want to stay away from editing wikipedia for weeks/months until I get the bad taste out of my mouth and think it's safe to get back in the water. My whole professional life has revolved around EM radiation so I think I should by now have some idea what these names mean in practice. And I never never heard about "mass deletions" except for vandalism nor the deletion of an image (which could have much more information than this table!) being described that way let alone violating some policy. I've seen large blocks of text, prose, with a much larger word-count or byte-count being deleted often for reasons short of being inaccurate and never that charge leveled. So you describing me that way makes me feel like I must be about the worst editor on wiikipedia outside of vandalism. And couldn't be the real reason someone wants to keep an out-of-date table rather than any number of other solutions which could involve a table, a graphic, or just a simple statement like I suggested above. So you can start by removing that bullshit accusation from your vocabulary. Interferometrist (talk) 17:20, 6 January 2022 (UTC)

I ended up choosing some critical words for an action of yours, and only when it became more problematic due to repetition after it was contested. That is not disrespect of you. I think that you are mis-interpreting it as such because you do not understand how (the weird alternate universe of) Wikipedia editing works. Because of that I won't take offense of your mis-describing what I said. That said, if you felt free enough to do that large deletion even after it was contested, why haven't you put in your proposed sentence which has received support?  :-) North8000 (talk) 17:42, 6 January 2022 (UTC)

You propose that you be treated with more respect...Well I'd propose you stop whinging about how badly you are being treated and cough up some sources that back up your position. That's how it works on Wikipedia, we follow reliable sources. We want subject experts like you to contribute, but you can't expect your qualifications to give you any special privilege. You have to support your contributions with sources when challenged, same as everybody else. And no one has mentioned vandalism until you just did. And yes, you are acting against policy, the WP:EW guideline, or at least coming extremely close to it. See WP:BRD for the expected way to behave. SpinningSpark 17:54, 6 January 2022 (UTC)

To put a point on that, if Einstein were a Wikipedia editor, he would not be allowed to write here based on his expertise. He would need to cite published sources (such as one of his books) North8000 (talk) 18:45, 6 January 2022 (UTC)

Oh again you are very insulting (perhaps unintentionally, but then carelessly) - of course I know that! I've been editing on wikipedia for at least 10 probably 15 years, especially on pages where I do objectively have expertise, and -- you can go look at all my edits on talk pages, you know how! -- not once have I ever pointed out that my formal credentials related to the subject matter meet or (in most cases) exceed theirs when arguing over content issues. Never! The only time I say anything about my expertise is when I need to point out that a subject is OUTSIDE my exact expertise, but I thought .......

However in this special case it actually is true that my expertise DOES exceed that of any published book, if only for the reason that books get published with significant lag times (let alone the 12 year old books cited in this discussion!) whereas my exposure to the prevailing linguistics is quite current. This isn't about science at all nor is it about top-down definitions such as there are for MW-HF-VHF-UHF for instance, it is about everyday usage and any written specification for the scope of these terms is, at best, written by lexicographers, not scientists who don't give a shit what you call a wave of frequency f just as long as we understand each other. So the way you would have to find reliable sources in this regard is by, for instance, searching for 10 or 50 papers on 1THz waves or 3THz waves and seeing what the authors call it in each case (usually in the paper title). I would say that "IR" should cover wavelengths where over 5% (or 2%, I don't know!) of those papers say "IR" and likewise for those who call it THz or microwave, and from that you can get some working "definitions" of those terms IN CURRENT USAGE which would involve large overlaps in their ranges, but that's alright. I'd be happy to write a table with those overlapping ranges based on my guesstimate of what such a study WOULD show but don't have the time (or motivation) to do the statistical data collection. I'm pretty sure that by the 5% criterion, 1000um would NOT fall within the "IR" range, probably not 300, but 100 would. For instance. But I'm kind of finished with making edits that are going to be reverted or lead to an editing "war" which is the last thing I wanted, just for wikipedia NOT TO BE MISLEADING, which did not lead to my ("mass") deletion of a table, but, if you look back at my first edit which was reverted, introducing into the text a disclaimer to the effect that the following table (which I did NOT delete) did not reflect current usage at least with respect to the supposed "boundary" between IR and THz (which it didn't even mention) and microwave. Interferometrist (talk) 23:12, 6 January 2022 (UTC)

"...books get published with significant lag". Those are secondary sources. Wikipedia, like all encyclopaedias, is a tertiary source and will necessarily lag even further. That's just a fact of life. Your suggestion of sampling a number of published papers (primary sources) and drawing a conclusion would be original research. That is something we don't do here. See WP:PSTS. SpinningSpark 23:24, 6 January 2022 (UTC)

Really, is that called OR? I know that secondaryh sources are expected but primary sources not ruled out. In the special case of a linguistic-only issue before the new dictionary comes out that looking at the typical usage among what would be RS's DOES answer such questions, and I don't think what you described is a good justification for wikipedia to be many years out of date. But if I'm completely wrong about the process, then at least insert into the text that definitions are rapidly changing as technology in these wavelength ranges explodes. Oh, come to think of it, that's what my first edit was trying to say, and it was immediately reverted. So I give up. Interferometrist (talk) 23:44, 6 January 2022 (UTC)

• Here's a 2019 book still putting the band edge at 1mm, despite the title of the book differentiating infrared and terahertz. The difference in terminology in both sources I have linked is more based on the type of detector being studied. Calling something terahertz is not proof that it is not considered infrared. Any more than calling an antenna "long wave" can be taken to mean it is not radio. SpinningSpark 17:06, 6 January 2022 (UTC)

Oh that's funny, I just clicked on that book (don't know why I'm even wasting my time with this!) and noticed table 1.1. It calls wavelengths out to only 100um "IR" but 100-1000 "submillimeter" which is synonymous with THz. But again, I'd support a table with greatly overlapping ranges in order to account for the non-exclusivity of these terms. And my estimate is that >100 is called IR often enough to include it but probably not >300. Interferometrist (talk) 23:57, 6 January 2022 (UTC)

Oh I should have looked more carefully: according to fig 1.1 this author exactly agrees with me. IR starts at 300 whereas THz extends to 30 with a 10:1 overlap in these terms: so what? Interferometrist (talk) 00:11, 7 January 2022 (UTC)

Comment on CIE Division scheme

The frequency ranges should be inverted as follows IR-A 430 THz - 215 THz IR-B 215 THz - 100 THz IR-C 100 THz - 300 MHz

Please acknowledge — Preceding unsigned comment added by Emi21701 (talk • contribs) 08:30, 21 February 2019 (UTC)

According to the CIE International Lighting Vocabulary (DOI:10.25039/S017.2020), IR-A starts at 780 nm, not 700 nm. The referenced article is only citing CIE without giving an original reference.

Valnar (talk) 18:07, 15 February 2022 (UTC)

Two passages with citations removed without explanation

See this diff: http://en.wikipedia.org/w/index.php?title=Infrared&diff=519847450&oldid=519847148 .

I have not delved into the sources to see if they are bunk or not, but removal of cited content without explanation is frowned upon. Would be good to have some words from the editor. --User:Ceyockey (talk to me) 23:27, 25 October 2012 (UTC)

Agree. I thought it was a poor removal myself. Discovery of an near IR sensing fish is neat, and certainly deserves ONE mention. If referenced, it's up to the remover to justify removing it again. I've cleaned out the names (we usually don't include names in these articles, except of REALLY famous scientists), and cut the mention of this primary paper to just once. Hopefully, that will fix the problem. SBHarris 00:34, 26 October 2012 (UTC)

Thanks, Sb ... glad I asked and received a 'second' on the poor removal. --User:Ceyockey (talk to me) 00:44, 26 October 2012 (UTC)

Wikipedia editing policy regarding linguistic usage issues

Hey, this is involved in the above discussion but is a separate issue regarding policy that I'd like clarified. Although sounding authoritative, I question SpiningSpark's interpretation of policy, and would like a second opinion. Because in the past I have certainly considered the language used in RS's as being part of the content, not just the author's preferred language used to refer to the content. I do not believe (and have not felt limited in other situations) that inferring linguistic use from a RS would be regarded as OR.

In other words, if in a RS it is stated "The Biggly moth lives in rock crevices" even though I had been searching for information on the Patagonia Red moth, then this could (I had assumed) mean that according to this author "Biggly moth" is an acceptable term for the one I had a different name for. Especially if I see the same name used in more than one RS. And that I could reasonably use that as evidence for the linguistic identification of these two terms WITHOUT an explicit statement in a RS that "the Patagonia Red moth is also referred to as the Biggly moth in popular literature." Have I been wrong?

Of course in this case, if I am indeed right, then SpinningSpark's objection above, calling what I might do "OR", is invalid. If I see 300μm radiation referred to as THz in most current RS's, then I am NOT doing OR by concluding that THz is or has become the preferred name for that radiation (whether or not "IR" also applies to it).

Could someone clarify wikipedia policy please? Interferometrist (talk) 15:15, 7 January 2022 (UTC)

I'm familiar with policies and guidelines but you posted a pretty complex bundle and tied it to another one and I would be reticent to try to respond.

What I can say is that under applying common Wikipedia policies and practices applied to this situation here, the best thing to do next is for you to propose a specific edit or edits in talk. I think that things would then go well. Sincerely, North8000 (talk) 16:50, 7 January 2022 (UTC)

Well I am just asking about wikipedia policy (ignore the fact that it might apply to the IR page) and didn't know where else to ask it (do you?). In particular I really want to know if the principle I assume (that the usage of terminology by RS's is valid evidence of its proper use) is accepted, or on the other hand that could be an OR violation. Someone must know!

Regarding the outcome of the current "dispute" on the IR page (the actual substance of which still puzzles me), I decided not to edit myself anymore since my edits were reverted on the basis of various objections. Anything I'd "propose" at this point I have already written or expressed to the point that anyone following this could as well propose such a draft. I really don't want to waste any more time writing things that could possibly be reverted; I just can't take it anymore. I had an earlier text that I thought was ok but reverted because it was difficult to read that could be revived, or re-written to remove that objection. I didn't consider it a final edit on the section but put the table in proper perspective without its "mass" removal. If there is agreement to go ahead with a table of overlapping ranges defined according to current usage, then I would be happy to input my estimates of what those limits should be (especially in the 10mm-100nm region), if I'm guaranteed that it won't be labelled OR or rejected outright as not being properly cited. I can say again, FWIW, that all of my experience in hearing these terms are based on papers that I come across or talks I go to in which the speaker already has RS publications generally using the same terminology they used in their talks. That's where I now stand. Interferometrist (talk) 17:54, 7 January 2022 (UTC)

My last response is the best I can do.North8000 (talk) 19:02, 7 January 2022 (UTC)

The example you give regarding moths is not only OR, but it is also a classic example of the fallacy of the undistributed middle. To answer your question about where to raise general questions on OR guidelines, that would be Wikipedia:No original research/Noticeboard. SpinningSpark 20:59, 7 January 2022 (UTC)

I have no idea what you're talking about and can hardly believe you even read what I wrote. This isn't about OR, it's about what words you should or shouldn't use and how that's decided. If you can't give me a more appropriate answer than that, or admit you don't know the answer like North8000 did, then I'll have to assume you are simply hallucinating. Interferometrist (talk) 19:16, 8 January 2022 (UTC)

I may well be tripping, but you were definitely talking about moths. You searched for "the Biggly moth lives in rock crevices", found "Patagonia Red moth" (presumably because it also lives in rock crevices) and concluded that Biggly moth is a synonym of Patagonia Red moth. It is OR to draw that conclusion unless you have a source that directly states that they are synonyms. It is OR to conclude that "Patagonia Red moth" is the accepted term, regardless of how many sources you have found using it, unless you have a source that directly states that. Your argument is a fallacy because, as a syllogism it reads,

Proposition 1: All Biggly moths live in rock crevices

Proposition 2: All Patagonia Red moths live in rock crevices

Conclusion: All Biggly moths are Patagonia Red moths (and vice versa)

It is a fallacy because the middle term "live in rock crevices" is not distributed in either proposition. That is, not all creatures living in rock crevices are Biggly moths (or Patagonia Reds).

You removed the table from the article on the grounds that the range of infrared listed includes terahertz radiation, but when challenged provide no evidence other that your own experience. That is OR. You claim that the source I provided is "checkmate" for me, yet table 1.1 titled "Division of infrared radiation" clearly has 1mm at the bottom limit and states 1mm is the boundary in text on the previous page. It is OR to conclude from that source that the 1mm to 100um band should not be counted as or called IR because it does not have IR in its band name. The source not only fails to explicitly state that, but indicates quite the opposite. You want an answer to what basis naming questions should be decided. On Wikipedia that answer to that is not to use your own OR and provide sources that directly say what you want said. So far, you have provided no sources so everything you say or claim remains OR until that happens. Sorry, I know you said you don't want to hear me bang on about OR, but it is inextricably linked to the question of how content issues should be decided. SpinningSpark 22:07, 8 January 2022 (UTC)

<sigh> You certainly are tripping. I don't know a damn thing about moths. What my made-up example was trying to say is this (please read carefully.....): If I inadvertently found out EVEN FROM RS's that two words were synonymous, whether it was possible for ME to say so (in an edit), without an explicit statement from a RS (such as a dictionary) saying that these two words are synonyms. I am sorry you read so much into or took so literally my example. The broader question is whether linguistic usage AS OBSERVED by an editor (especially just using RS's, though I may well have gone further) can be reported as a fact on wikipedia without a specific statement about the usage (i.e. by a lexicographer or in a glossary of a RS) of those terms. I had always thought so and proceeded as such, but wanted clarification on Wikipedia policy. That's all, and it's alright if you don't know the answer for sure or can't point to precedents where this issues was decided, in which case your humble silence will indicate that you, like North8000, don't really know (perhaps no one does). Interferometrist (talk) 23:20, 8 January 2022 (UTC)

Your moths analogy has confounded the issue. There are various venues I coukd suggest where policy issues can be discussed, but I don't think we're there yet - I can't work out what you're actually asking. I suggest that you explain, as succinctly as you can, what change you think needs to be made, and what source/s you would use to support that change. Keep it focused on the content here, don't resort to analogies or make comparisons to other situations - that will just confuse things. Girth Summit _(blether) 23:43, 8 January 2022 (UTC)

Me too. North8000 made a similar request earlier. My silence from here on does not mean I don't have answers on guidelines. It only means there is not a definite proposal for me to comment on. SpinningSpark 06:46, 9 January 2022 (UTC)

Yes, your next step should be to do what Girth Summit just said, Spinningspark reinforced, which I am reinforcing now, and which I said previously. North8000 (talk) 20:10, 2 July 2022 (UTC)