Talk:Optics

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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

[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)

____

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)