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I have a theory, optical physics related (pinhole optics)

by Nutrient
Tags: optical, optics, physics, pinhole, theory
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Nutrient
#19
Apr29-14, 11:29 AM
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Quote Quote by ZapperZ View Post
That is your age, not your background in optics, unless you are equating your age with the standard level of understanding that kids that age should have in understanding optics/physics.

If so, how were you able to understand "conformal microscopy"?

Zz.
I'm not actually 12, haha.

But that would probably be about as much as I know, yes.
ZapperZ
#20
Apr29-14, 11:51 AM
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Quote Quote by Nutrient View Post
I'm not actually 12, haha.

But that would probably be about as much as I know, yes.
Then my question still stands. You gave us a link to conformal microscopy to "support" your scenario. I question whether you actually understood the physics of such optics and why you would use it as a reference to back up your claim.

Please note that, unlike other science forums, this forum actually have real physicists, engineers, mathematicians, and other scientists. There is a good chance that if you are using an idea in physics to support your claim, that there's someone here who either knows the subject area, or have even worked in that area! So unless you know exactly what it is that you are citing as references, then I'd suggest you either ask for clarification, or try to learn from what you've been given. Otherwise, you will look very foolish when someone else points out that you didn't know what you are citing.

Zz.
Drakkith
#21
Apr29-14, 01:00 PM
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Quote Quote by Nutrient View Post
Hubble uses long exposure too.

Here is the basic idea:

1. Limit viewing area to a small hole before the image is magnified.
2. This shouldn't effect how the lens works, it would simply lengthen the area between the focal point.
3. Use higher illumination to improve detail of resolution, taking advantage of the dimming effect.

About my background in optics, I am 12.
Resolution in a microscope depends on gathering as much of the EM wavefront as possible. Using a pinhole directly counteracts this and would do nothing but blur the image.

http://en.wikipedia.org/wiki/Diffraction_limit
Andy Resnick
#22
Apr29-14, 09:22 PM
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Quote Quote by Nutrient View Post
My question is this, could this same pinhole application of viewing clearly be useful in optical microscopes? And if so, can it be used in series?
First, the 'pinhole method of seeing without glasses'. Yes, it works very well. By stopping down a lens (the pinhole is located at the entrance pupil of your eye), aberrations (except for distortion) are reduced. Further, while stopping down a lens does not alter the field of view, the throughput does get reduced.

However, this would be a terrible idea for a microscope. Why? Because unlike the eyeball which has a magnification much less than 1, microscopes have magnifications much greater than 1. Stopping down a microscope objective (like any lens) increases both the depth of field and blur circle diameter, neither of which are desirable.

Confocal microscopy doesn't put a pinhole at the entrance (or exit) pupil of the lens, but rather a plane confocal to the object (hence the term 'confocal'). That is, a pinhole is imaged onto the sample. This is the origin of improved performance as compared to a widefield technique. To be sure, confocal microscopy can be performed with many pinholes (Nipkow disk) to increase image acquisition rates.

Now- pinhole cameras (camera obscura). The pinhole is located at the entrance pupil, and indeed, camera obscuras have very low levels of aberrations, large fields of view, and miniscule levels of throughput.

How about using a pinhole on a telescope? Indeed, they are used as part of a Hartmann-Shack wavefront sensor, a common component of adaptive optical systems. Otherwise, since you are manufacturing the telescope optics to be well-corrected in the first place, using a pinhole will only decrease your throughput.

Hope this helps.


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