Optics is the study of light, and its interaction with matter. It includes topics such as imaging systems, fiber optics, lasers, quantum optics, and more.

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Mechanism for visible light frequency mixing in storm clouds

So I know that when red and blue light (or the frequencies/wavelengths we percieve as such) hit our eyes with the correct proportions, our eyes and brains interpret that as the color purple. In ...
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1answer
53 views

Is the formula, for finding the distance between two slits, my books gives correct?

In my book'a section on Young's double-slit experiment, the formula, $d = m \lambda \sin\theta$, is given. In this equation $d$ is the distance between two slits, $\lambda$ is the wavelength of light ...
2
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1answer
22 views

Is circular masking a laser beam an acceptable way to get the beam diameter you require?

I am wondering what are the down sides to just masking a laser to get the beam diameter you require? For example if you have a collimated eliptical beam of say 2mm width and 4mm height, but you ...
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0answers
4 views

Blazed phase profile to generate laguerre gaussian beam

How to add blazed grating to a fork grating to achieve maximum diffraction efficiency in the first order while generating laguerre gaussian beam?
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1answer
77 views

Is this diagram, concerning Young's double slits, inaccurate?

"This diagram" : My question is whether those lines (interference) have to originate from a single point. The diagram used to demonstrate what $m$ (path difference) means, has two lines originating ...
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3answers
44 views

What is the total internal reflection?

From what I read, it sounds like when a light ray passes from one medium to the other, if the critical angle is reached so that the refractive ray is at 90 degree with the normal, the light ray does ...
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0answers
22 views

Does light accelerate when it meets a surface? [duplicate]

Does light accelerate when it meets a surface like mirror, we know that light changes path when it meets a surface like mirror.If light changes path,even if travelling at c,this means light has ...
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2answers
247 views

Light-matter interaction and an object's appearance

I am taking a course in Computer Graphics, and the teacher said we could put materials in there main categories: mirror like glossy or specular diffuse He suggested that the law of reflection is ...
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1answer
32 views

is copper a non-magnetic?

I'm working on an optics project that I'm using Fresnel Equation for Intensity. but I've got a question, is copper a non-magnetic ? You know because in Fresnel Equation, for non-magnetic materials ...
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0answers
17 views

Maximum angle of a prism to have an emergent ray [on hold]

the critical angle of the prism ABC is 40degree. for a ray of light incident on AB , to emerge from the face AB , what should be the maximum value of angle A? please explain how to do this ...
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0answers
12 views

What's the difference between two types of diaphragms?

What's the principal difference between aperture iris diaphragm and field iris diaphragm?
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1answer
15 views

Does “converge” mean intersecting and producing image when we are taking about convex lenses?

After reading the chapter on convex lens, I saw several places where "converge" is used. In the very beginning of the chapter, my book says "converging lenses bring light together". So I thought ...
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1answer
67 views

What is the frequency of the color black?

Our eyes don't see light; they detect vibrations in the 400-800 THz range that we call color. Since our eyes can detect the color we call black, what is its frequency?
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7answers
4k views

Why did high quality mirrors use aluminum coatings instead of silver?

I have two questions on mirrors. I’ve read that in the past quality mirrors were coated with silver but that today vacuum evaporated coatings of aluminum are the accepted standard. When I look at ...
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0answers
13 views

What is the wavelength of the light and how far away from the central maximum are the first and second maxima? [on hold]

A single, monochromatic light source is shined through an etched, flat prism with a slit separation of 0.025mm. The resulting interference pattern is viewed on a screen 1.25m away. The third maximum ...
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0answers
18 views

What is the small angle measurement from the central maximum to the first maximum? [on hold]

Two thin slits with separation of 0.0200mm are placed over monochromatic red laser of wavelength 632nm. What is the small angle measurement from the central maximum (zero degrees, in-line with source) ...
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5answers
539 views

Why does an image form at the intersection of light rays?

If image is simply what we see, then why, when light rays bend in the atmosphere, enabling us to see the sun, is there no intersection of rays? The concept is strange. I can not relate it to ...
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2answers
16 views

How are aberration levels measured?

I was reading reading the paper: Predicting subjective judgment of best focus with objective image quality metrics when I come across this statement: Through-focus visual acuity (VA) was ...
3
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0answers
206 views

Is it possible to calculate the work function of a metal with basic lab equipment?

ive been given a problem in physics, its to prove if a lump of metal we have been given is real gold or not. one way to to do it would be to work out its density, which is fairly easy, mass/volume. ...
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4answers
397 views

Is it possible to surpass the diffraction limit for telescopes?

Telescopes have angular diffraction limit depending on the observed wavelength and aperture diameter. I've read that it's possible to go beyond the limit for microscopes. But is it possible to do the ...
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2answers
1k views

Eliminating IR light reflection perceived by a steep viewing angle

I am having a problem with reflection on an acrylic surface, in the IR part of the spectrum. This reflection is interfering with an algorithm that looks at objects, as it makes two show up when only ...
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0answers
10 views

When to use lateral magnification vs angular magnification?

What is the essential difference between lateral and angular magnification (like why do we need to use both and when do we use which)? Also, is there a relationship between the two magnifications?
3
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2answers
3k views

Wavelength-dependent refractive index

I read in a book about optical fibers that the different spectral components of a light pulse transmitted in the fiber propagate with different velocities due to a wavelength dependent refractive ...
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0answers
60 views

General proof of formulas of geometric optics?

In most lf textbooks formulas of geometric optics like lens maker formula and base formula for that are proven (or rather verified from my point of view) by taking specific case (ray diagram) and ...
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1answer
23 views

Recreating an image from a photometer or similar light-detecting device?

I'm thinking if it is possible to recreate an image from data from this kind of device. It is known analog signals theoretically have infinite resolution, but since we use them in discrete systems ...
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0answers
30 views

Visible wavelengths of air fluorescence data - needed for school demo laser telephone design

I'm seeking information about fluorescence in visible wavelengths (390-700nm) of any of the main constituents of air ( $ N_2, O_2, CO_2, H_2O, CO, etc. $) that can be excited with a (hopefully ...
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2answers
43 views

Why is the index of refraction different for different wavelengths? [duplicate]

The index of refraction can be written as $$n=\frac{\lambda_v}{\lambda_m}$$ where $\lambda_v$ is the wavelength in a vacuum and $\lambda_m$ is the wavelength in the medium. I’ve been told that since ...
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2answers
111 views

Is the plane wave model always valid in reflection and transmission?

my question is related to another one I asked, but I foolishly made that question about several things (experiment, computation, theory) at once so it was confused. I was talking to my boss about ...
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2answers
191 views

Alternate young double slit experiment

What will happen in young's double slit experiment, when instead of screen I put a black screen with a hole and a second screen behind the black one. Will it still form interference pattern albeit a ...
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2answers
51 views

Red light in the depths of the ocean

I've read that fish in the deep ocean tend to be red because it makes them look black for other fish, thus reducing their chance of being eaten. Why do they look black?
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2answers
132 views

Examples in which the light maximizes the optical path length

I posted a similar question about geodesics on Math.SE. Many sources (Wikibooks for instance) claim that the light could maximize the optical path length in some cases. But I don't think it's actually ...
2
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1answer
46 views

Optics phenomenon with my glasses?

When I look through my glasses toward the extreme left, a very odd and intriguing phenomenon occurs: The border of everything I see is lined with a hazy blue lining on the left and a hazy yellow ...
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0answers
16 views

Can I use an optical long-pass filter as a short-pass filter if I just collect the reflected light?

The transmission spectrum filter of long-pass filters are often better shaped than short-pass filters because long-pass filters are often specified for use in a very broad region from 200nm to 2200nm. ...
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2answers
425 views

Finding the illuminance from a triangular light source

Since most light sources in games are point-like, it's pretty difficult to approximate area light sources with point sources. As triangles are a universal form to represent 3D models (thus area light ...
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1answer
15 views

White light polarization by ground\sky

Why does light from the sun gets a slight (horizontal) polarization after bouncing from the ground? And same question for light which is scattered from the sky. Thanks.
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1answer
166 views

Why are mediums always represented as straight and parallel lines in Ray optics?

I have been reading Ray Optics lately and I always see that the interface between mediums are always represented as Straight lines in ray diagrams. There is no mention that they are considering an ...
0
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1answer
25 views

How to polarize a laser beam

I'm working on an optic project that I need my laser beam to be polarized. Do you a simple way to polarize my laser beam?
2
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1answer
23 views

Why does normal incidence eliminate the photocarrier effect radiation in this experiment?

Here's a paper in which they use GaAs crystals at a few orientations to produce THz radiation, by means of Optical Rectification (OR). That's actually not what this question is about, though. They ...
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0answers
21 views

Is there a limit to telescope resolution? [duplicate]

Could a strong enough telescope read a newspaper on a planet 1400 light years away, or is there a theoretical limit to the resolution of magnification?
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0answers
149 views

The optics of vortex (in water): why there is a bright ring?

This picture is from this YouTube video from "Physics Girl", which shows how you can generate vortices in a swimming pool by using a plate: And there she explains the creation of the shaded circle ...
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0answers
62 views

How can I precisely measure the intensity of the Hydrogen Alpha (Balmer) line at low intensities?

I assume that I will need some kind of very precise filtering, but how is that accomplished? After that, photon counting at worst, but I am expecting millions of photons per second. The background is ...
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0answers
33 views

Is the human eye diffraction limited, or is there another limiting factor?

I know that most problems involving the human eye in my undergrad physics text book tell the student to treat the human eye as a diffraction limited system (ie to assume the only factor limiting human ...
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1answer
54 views

Inside a spherical mirror

imagine standing inside a sphere composed entirely of mirror surface; what does this look like? inside is lit by an invisible light source if each point encounters a reflection of itself, what is ...
2
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1answer
45 views

Are shadows cast on mirror surfaces?

While moving an object between a light source and a clean mirror surface, its shadow seems hardly visible (at least compared with a non reflecting surface). Is it correct that the shadow is not ...
2
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1answer
86 views

Spatial coherence of SLED light (width of active region?)

As far as I know, super-luminescent diodes (a.k.a. SLEDs) have a very similar structure to laser diodes, except that the front faces of the active region are tilted to prevent the sort of reflections ...
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20 views

Imaging and the Electric Field

In this book (pg. 162), it mentioned that conventional lenses only focus propagating waves, thereby creating an imperfect image. In contrast, superlenses focus both propagating and evanescent waves, ...
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0answers
30 views

Intensity measurement of light

How can I understand which color my camera is more sensitive to? How do I calculate the intensity from a picture? My understanding: Calculate the value at one pixel and just integrate with total ...
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0answers
19 views

Single slit diffraction treated as a differential equation

I want to find the values of electromagnetic fields that result from single slit diffraction. This should be possible by solving maxwell's equations for appropriate boundary conditions. But I'm not ...
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0answers
17 views

Deviation on the Diffraction Pattern when not perpendicular

Due to Babinet principle, Diffraction pattern of an opaque .... ( you all know ). here my opaque is my wire. So, I know that if I change the angle between beam and wire ( I mean if I don't aim the ...
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1answer
40 views

Different colors and Metamerism

Given the following graphs: They describe the response for two different colors . In addition that both colors are metamerism. My question is why? how can I prove it? Update: How can I draw ...