Talk:Optics

From Wikipedia, the free encyclopedia

	Portal This article is within the scope of WikiProject Physics, which collaborates on articles related to physics.
B	This article has been rated as B-Class on the assessment scale.
Top	This article is on a subject of Top importance within physics.
Help with this template This article has been rated but has no comments. If appropriate, please review the article and leave comments here to identify the strengths and weaknesses of the article and what work it will need.

	This article has been reviewed by the Version 1.0 Editorial Team.
	This article has been selected for Version 0.7 and subsequent release versions of Wikipedia.
Additional information: Start This article has been rated as Start-Class on the assessment scale. Feel free to make short comments here to identify the strengths and weaknesses of the article. ??? This article has not yet received an importance rating on the assessment scale. This article is one of the supplemental core articles, which every encyclopedia should have.

Suggestion: Anyone planing to follow all those broken wiki-links in the page? I am giving it a shot but would appreciate help as it is a tiresome job. Thanks, askewmind 00:29, Feb 17, 2005 (UTC)

Q: Are there any direct connections over optics and information theory? It is listed at 'Other optical fields'. --HarpyHumming 19:27, 28 Feb 2004 (UTC)

Contents 1 No mention of Mechanical? 2 Missing article "Optical" 3 Capitalization 4 Split Off "Geometric Optics"? 5 Quantizing 6 Education/Training Section? 7 Ion optics 8 Work needed 9 Branch of physics? 10 Removed from article.

[edit] No mention of Mechanical?

In my work, We design various optical systems within our product. The EEs design the electronics which cause the LED to illuminate. They also design the circuits which senses the current passing through the devices which react to light. Everything in between seems to be mechanical. Light pipes, Prisms, Lenses, Mirrors, angles, Textures and materials. I've always considered Optics to be everything that goes on in between the source and the detector. The medium itself may be electromagnetic in nature but MAKING IT USEFULL requires mechanical manipulation. Light is whats there, Making it useful is optics. Any reason why the mechanical aspect of optics has been missed in this wikipedia entry?

I don't know what you mean by "mechanical" here, or why you think it is missing. Optics includes anything that manipulates light. That would include light pipes, prisms, lenses, mirrors, angled reflecting and refracting surfaces, and scattering from textured surfaces. There is an unfortunate tendency in industry to assume that optics is something that naturally falls in the purview of a mechanical engineer (since it's clearly not an electrical problem). I would hate to encourage that. Opticals is a specialized discipline in its own right, not a subtopic of mechanical engineering.--Srleffler 01:20, 15 November 2005 (UTC)

There is a field called either "optomechanics" (41k hits on Google) or "opto-mechanics" (84k hits on Google) related to the mechanical aspects of optical design (for example, does my compound lens stay in focus if the temperature changes?). Unfortunately there doesn't seem to be a WP article on it. -- The Photon 06:23, 7 January 2006 (UTC)

[edit] Missing article "Optical"

There is a redirect to this page from the article Optical, which describes an important musician within electronic dance music (referenced on a fair number of pages) - does anybody know how to fix this (and recreate the original article) or set up a disambiguation page? I'm quite new to this and haven't worked it out yet. Will Lakeman 13:06, 20 May 2005 (UTC)

Usually when there's a clear primary usage of a word, that's left at it's current page, while others are placed at, for instance, optical (musician). In cases where it's possible people can get confused but one is clearly the major usage you can put a diambig sentence at the top of the article. If there are multiple alternative uses that link can be to a disambig page (ie Ontario or operator), but I think where possible disambig pages should be avoided. Official guidelilnes can be found at Wikipedia:Disambiguation specifically the section on types of disambiguation.--Laura Scudder | Talk 18:07, 20 May 2005 (UTC)

Thanks Laura, the page was under Optical (artist). I have inserted a sentence at the top of this page, although I'm not entirely sure I've got the format right, re: italics and boxing etc. Will Lakeman 19:46, 22 May 2005 (UTC)

[edit] Capitalization

I am not much on these details, but I think I have seen Physical Optics in capitals. I am not sure about Gaussian optics. Quantum mechanics is not capitalized and maybe not born approximation, but Physical Optics is a less common approximation and tends to be confusing in lower case, because on can so easily take it literally.

My sense is that quantum mechanics, Gaussian optics, Born approximation are the correct capitalizations. I don't know about Physical Optics. — Laura Scudder | Talk 20:03, 4 September 2005 (UTC)

Gaussian, etc., in captials because it's a proper name. Otherwise, standard wikipedia style is not to use capitals in article titles. -- DrBob 23:06, 4 September 2005 (UTC)

[edit] Split Off "Geometric Optics"?

Per my discussion with User:Srleffler on the Talk:Nodal_point page, it seems wikipedia needs a discussion of geometric optics, and I think it should perhaps be separate from this article. Any thoughts on that?

Specifically, my interest is to see it explained somewhere in wikipedia why all light passing through a central shutter is evenly distributed over the entire image frame that results (as opposed to the wrong idea that light which passes through the center of a central shutter ends up in the center of the image frame, light that passes near the edges of a central shutter ends up at the periphery of the image frame). —Severoon 19:57, 24 February 2006 (UTC)

There is more than enough to say about geometric optics to justify a separate article about it. All that is needed is someone with the expertise and the time to tackle it.--Srleffler 04:12, 25 February 2006 (UTC)

I've still got my well loved copy of Fundamentals of Optics by Jenkins and White hanging around. A bit busy teaching during the school year, but adding some meat to a geometric optics article would be a lot of fun over the summer. :) -Tjkiesel 17:07, 1 January 2007 (UTC)

____

Think about a pin hole camera. In geometric optics, the rays are straight lines, so a ray passing through the center of the lens or through the pinhole continues at the same angle and reaches the ccd or film on the opposite side. (So you have to turn the film upside down.) David R. Ingham 05:55, 26 February 2006 (UTC)

This is a good start, but doesn't really explain the phenomenon in an optical system using an aperture or central shutter. The reason this explanation does not satisfy is that, with a pinhole camera, if you increase the size of the hole the effect is that the image is destroyed. With an optical system, however, changing the size of the aperture doesn't degrade the image at all, nor does light passing through a particular part of the aperture fall on a corresponding part of the image frame.

I don't mean to mislead anyone—I myself understand the phenomenon, I simply don't have the time to memorialize it on these pages with the polish required for the article. The answer to my question becomes evident when you consider a single point source of light. The front element of the lens gathers light rays emanating from the point source and directs them toward the aperture. The aperture allows some of these light rays to pass, which then fall on the back element. Assuming the point source is in the focal plane of the lens in its current configuration, the back element of the lens will cause all of the exiting light rays to converge to a point. If you picture the path of the rays through the lens, you can imagine the effect on the image frame if the point source were to drift upwards and to the right in the focal plane: the point on the image plane will move down and to the left.

Once it is clear how a lens handles a point source, it's easy; a more complex subject than a point source in the focal plane is nothing more than an array of point sources. The rays emanating from each point source pass light through the entire aperture. Make the aperture smaller, therefore, and the effect is not to vignette the image frame, but instead to decrease the luminosity of each individual point.

This explains why only point sources of light in the focal plane are in focus in the image frame. Those point sources that fall in the focal plane will converge to a sharp point on the image frame. Those point sources behind the focal plane will converge to a point behind the image plane...at the image plane, this will manifest as an aperture-shaped blur. Those point sources in front of the focal plane converge to a point in front of the image plane, which manifests on the image plane as an upside-down aperture-shaped blur. This also makes clear how aperture and sharpness are related...with a small aperture, a substantial movement of the point source out of the focal plane is required to make a given size blur on the image plane, whereas with a large aperture, a much shorter movement corresponds to the same size blur.

Are the images below of use to you? I made them for another purpose yesterday. If needed, I could prepare modified versions for use in an article.--Srleffler 21:53, 26 February 2006 (UTC)

Cooke triplet, 80 mm f/5

Cooke triplet, 80 mm f/10

[edit] Quantizing

Optics was pretty much classical even after Planck's famous explanation of blackbody spectrum in terms of quantized radiation, and Einstein's explanation of photoelectric effect interpreted as implying that light itself is quantized. Instead of arguing over them, I just pinned to the rise of quantum optics. OK? Dicklyon 03:55, 5 October 2006 (UTC)

[edit] Education/Training Section?

It would be nice to have a section discussing the training one needs to pursue a career in optics. I would have found this incrediby useful back when I was looking at grad schools. Here is some stuff to put in it: -Most people obtain undergraduate degrees in EE, ME, Physics, Math, etc. then go on to pusue graduate degrees or training in optics. -List of "top" schools in optics (University of Arizona, University of Rochester, University of Central Florida, etc

To be fair, that would be done when the article is more of an overview of optics and less a listing of topics within it. I've not seen an article yet that goes into much or any detail on jobs within that particular area, so i think once the article is referenced and well-rounded, maybe there could be something like that added.

For instance, the article on Chemistry, there are no results for "job" or "career". Don't know why, perhaps it's just the fact that it may impinge upon POV? J O R D A N ^[talk ] 14:35, 23 January 2007 (UTC)

A section on the training one needs to pursue a career in a field might be OK, but attempting to list schools with programs in a discipline tends to cause problems. The article on photonics used to have such a list, but it slowly grew to be an excessively large part of the article. I removed it, because it violated Wikipedia is not an indiscriminate collection of information. We're not a directory of University programs in optics. In principle, listing a few "top" schools could work, but only if there is an NPOV means of deciding which few schools are the "top" ones. Otherwise, it becomes a directory of every school with a program in Optics.--Srleffler 16:32, 23 January 2007 (UTC)

[edit] Ion optics

Aren't ion optics a type of optics and thus shouldn't they bear mentioning here? If this is the case, the intro has to be changed to include more generality about any particle rather than just photons. Wikipedia brown 21:38, 15 February 2007 (UTC)

I would prefer to keep the narrower view of what "optics" is, for this article. From that point of view, "ion optics" is not part of optics per se, but rather uses the word "optics" metaphorically—ion optics is related to ions in the same way that optics relates to light. It's similar to atom laser. An atom laser is not a laser, but rather is an device in which atoms become coherent in the same way that light becomes coherent in a true laser.--Srleffler 23:14, 15 February 2007 (UTC)

[edit] Work needed

I reviewed this article for Version 0.7, and I don't think it should be rated as B-Class, especially considering the breadth and importance of the topic. Much of the content consists of lists rather than prose, and I don't think the article is very comprehensive (what about a history section, for example). Also, the referencing is weak. I would suggest expanding with prose then using of the Wikipedia:Summary style where appropriate. Walkerma 07:53, 18 September 2007 (UTC)

[edit] Branch of physics?

[Copied from User talk:Oli Filth]:

i notcied u changed my small edit to optics as being branch of physics. Am thinking we should not call it a branch since its merely based on electromagnetism, i mean there are no fundemental laws of optics, there all based in electromagnetism(thats what light is). Lastly, even on the physics page its not listed as a branch of physics or a core theory but merely a sub-branch of electromagnetism. Am thinking we should call it a branch of physical science since thats how its listed on encyclopedia encarta. —Preceding unsigned comment added by 24.36.181.171 (talk) 03:06, 9 April 2008 (UTC)

I reverted the change from "physics" to "physical science", because both are correct and the former is more specific. As to whether optics is a "branch" of physics, I think that's a good topic for discussion here. Optics is an odd discipline. Moreso than most other areas of physics it crosses over into engineering and technology. Optics is as much a "branch" of engineering as it is of physics. I'm not sure your argument based on fundamental laws holds water, though. There are certainly laws of optics, such as conservation of étendue. Such laws are not, of course, fundamental, but neither are the laws of thermodynamics. "Laws" are not generally very important in modern physics, anyway. Theories are much more powerful.--Srleffler (talk) 03:57, 9 April 2008 (UTC)

I like the change from "is a branch of physics" to "is a science". --Srleffler (talk) 03:09, 10 April 2008 (UTC)

[edit] Removed from article.

Removed the following:

Ibn al-Haytham is regarded as the father of optics for his influential Book of Optics, which correctly explained and proved the modern intromission theory of vision, and for his experiments on optics, including experiments on lenses, mirrors, refraction, reflection, and the dispersion of light into its constituent colours. He studied binocular vision and the moon illusion, speculated on the finite speed, and rectilinear propagation of light, and argued for the corpuscular theory. Due to his formulation of a modern quantitative, empirical and experimental approach to physics and science, he is considered the pioneer of the modern scientific method and the originator of experimental science and experimental physics, and some have described him as the "first scientist" for these reasons.

The claim that al-Haytham "is regarded as the father of optics" would need a citation, and would need to say who regards him as such. (I don't doubt the truth of the claim, but it is not suitable for WP as-is.) The same is true of the statements involving "he is considered" and "some have described". Wikipedia requires such statements to specify who holds that point of view, and may require a citation.

I removed the whole paragraph because it doesn't belong in the introduction and the article doesn't currently have a history section. (See History of optics.) If someone wants to expand the article to give a summary of History of optics including a discussion of al-Haytham's work, that would be great.--Srleffler (talk) 21:42, 12 May 2008 (UTC)