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.

learn more… | top users | synonyms

0
votes
0answers
6 views

Derive phase shift equation for two diffirent optical paths differences

i have question. If we have two optical paths differences, call them $\phi_1, \phi_2$, and $\phi_1 > \phi_2$ then phase shift with respect to optical path difference $\phi_2$ is $PhSh = ...
0
votes
0answers
6 views

Limits on the information obtained through optical measurements

Consider a Gedankenexperiment shown in the figure below. There are two lasers $S1$ and $S2$ with exactly the same specifications on paper. In practice, they are of course somewhat different but ...
0
votes
0answers
12 views

images formed by refraction

While deriving the formula for image formation by spherical refractive surface we assumed that object is placed at the principal axis and is like a point object. What if the object is not placed at ...
0
votes
0answers
5 views

image motion for projectile motion of object

a ball is projected from top of the table with initial speed u at an angle of inclination 'a' to the table. describe motion of image with respect to the ball on a screen located next to the table My ...
1
vote
0answers
15 views

Plane wave conditions

Which conditions have to be fulfilled in order to approximate a light beam by a plane wave (i.e. $\phi(x)\approx \phi(0)e^{ikx}$)? I am looking for both mathematical and experimental conditions. At ...
1
vote
1answer
26 views

Reflectivity of Metals - real and imaginary part of k-vector and complex dielectric function

De electric field component of an electromagnetic wave that is traveling in the $x$-direction is given as $$E(x,t) = E_0 e^{i(kx - \omega t)} $$ with $E_0$ the amplitude and $k$ the wave vector. From ...
0
votes
1answer
25 views

Optical path difference

Hello, i have question about calculating optical path difference. $\Delta L = (BC+CD)*n2 - BF*n1$ - why calculating path difference here we are substracting $BF$ segment?
0
votes
1answer
37 views

Oberving a photon through double slits

If we send a particle with mass through the double slits we observe a interference pattern. That is of course if we don't observe which slit the particle goes through. If we do then we get two peaks ...
2
votes
3answers
84 views

Violation of conservation of energy?

Imagine a perfectly spherical mirror with 100% reflection. Imagine a point source of light in the center. The point source keeps radiating light. Will the light undergo destructive interference ...
0
votes
0answers
15 views

Any good reference on crystal optics?

I am primarily interested in the birefringence phenomenon. Any good reference? I want something above the general physics level.
1
vote
0answers
6 views

How does voltage sensitive dyes actually determine neural network in foetus?

In research topics of neurophotonics, the best way of determination of neural network in foetus is by using voltage-sensitive dyes instead of placing diodes. But how does it actually work? Sorry if ...
0
votes
1answer
24 views

Can someone give an intuitive understanding of Fano Resonance?

I'm reading about Fano Resonance. The line that almost every source I can find gives is something like (from the wiki): The Fano resonance line-shape is due to interference between two ...
1
vote
2answers
23 views

Measuring image distance of a virtual image

How to a measure image distance of a virtual image without calculation? It is impossible? To measure it, we must have a real image to measure the image distance with a screen and a ruler. I saw it ...
0
votes
1answer
37 views

What does this problem about lenses really want? [on hold]

This is the problem: The distance between the lens of a simple remote camera (means it's not used to take pictures of close things) and the film is 40mm. how much should we move the lens to get ...
5
votes
1answer
43 views

Long, blurry reflections in wet road [duplicate]

When driving on a wet highway at night, any surface emitting or reflecting light will have a reflection right under it that is blurry and seems to stretch to infinity. This is not exactly what I am ...
1
vote
0answers
6 views

difference between plasmonic wave plates and usual wave plates

plasmonic waveplates are constructed using the generation of surface plasmons. Is there any difference between these plasmonic wave plates and the usual wave plates used in optics, besides the ...
3
votes
2answers
46 views

Decoherence of a Coherent Beam

If retarding films (i.e. wave plates) can retard the electric components of light (based on the films thickness) without affecting it's direction, couldn't I use a retarding film of randomly varying ...
1
vote
0answers
49 views

Is it possible for someone traveling at the speed of light to see at all? [closed]

I know that the speed of light is the same for all observers regardless of your speed, But this question is really worth thinking about. If someone let's say managed to reach the speed of light, ...
0
votes
0answers
14 views

Wavenumber separation for a source containing hydrogen and deuterium [closed]

I'm trying to solve the following question: The hydrogen line at $656.3nm$ emitted from a source containing hydrogen and deuterium is studied using a Fabry-Perot etalon of $0.5mm$ spacing. The ...
1
vote
0answers
36 views

Can anybody explain about phase shift and phase spectrum terms in case of multidimensional signal?

I know about phase of a 1D signal, but when I move into higher dimensions like 2D or 3D etc, it becomes headache to grasp the concept. What do the terms "phase shift" and "phase spectrum" mean in ...
1
vote
1answer
26 views

Polarization and Reflection [duplicate]

The polarization is a property of waves that can oscillate with more than one orientation. Given this, when the light is reflected from a surface, does the reflection change the property/orientation ...
2
votes
1answer
40 views

Why Image is not enlarged if we keep convex lens first and concave lens at last?

Well After successfully getting some concave and convex lens I started observing. At first I saw that if we keep concave lens near to your eye and just after x distance away if we keep convex lens we ...
2
votes
1answer
30 views

How much UV is reflected by glass?

On a sunny day, how much of the Sun's UV is reflected by windows? I suppose this boils down to what are the refractive indices of common window glasses, so that one might solve the Fresnel equations. ...
0
votes
0answers
18 views

Is polarization a meaningful notion for an EM mode in a close cavity?

For a generic close cavity, I suspect that all the modes are non-degenerate? Therefore, in each mode, at each point, the E field has a definite direction, and consequently, it is meaningless to say a ...
2
votes
2answers
35 views

Is the photon truly not absorbed in Raman scattering?

In reading about Raman Scattering, I was thinking while reading it "okay, incident photo absorbed by molecule, molecule goes to higher energy vibrational state, molecule re-emits photon with either ...
-1
votes
0answers
15 views

Why don't we see a totally circular rainbow in the sky [duplicate]

We know that the rainbow is formed due to the scattering of light. We always see the rainbow in a semicircular style. Does it is possible that we can ever see a totally circular Rainbow.
1
vote
1answer
29 views

Plane Mirror as the Screen in Young's experient

If I place a plane mirror instead of the screen in the Young's double slit experiment, what will I see? Will the bands appear on the mirror face?
3
votes
0answers
33 views

3D movie optics mathematics

I get the idea that we use two polarized light sources and a parallax rendered film such that the objects seem to resemble true parallax in our eyes once it passes through the polarized glasses, but ...
1
vote
1answer
63 views

Propagating higher order Hermite Gaussian modes. What are complex amplitude coefficients?

I've been tasked with writing a code (in MatLab, but I'm currently using Mathematica because I don't know MatLab %\ ...) to simulate the propagation of a Gaussian beam. I don't really know anything ...
0
votes
1answer
22 views

hexagonal patterns when we look at bright light or sun

when we look at bright light or sun, we many a times hexagonal patterns are observed. these are easily observed when we click their images. why all this happens? is all this is just a lens flare or is ...
1
vote
0answers
20 views

coherent length measurement of a monochromatic laser source

i need to learn about how to measure coherent length of a monochromatic laser source.I know that I can use michelson interferometer or spectrometry.For laser which has long coherent length michelson ...
1
vote
1answer
28 views

Position dependent refractive index [duplicate]

How to determine the angle of refraction when the medium has position dependent refraction index? Lets say that the angle of incidence on the glassy slab is $\theta_1$ and the ray goes through the ...
2
votes
0answers
23 views

Rayleigh scattering equation for optical frequencies

I would like to know if there is an empirical/generic equation for Rayleigh scattering at optical frequencies in the atmosphere, similar to the Mie scattering model from Kim and Kruse which states ...
1
vote
0answers
21 views

Disadvantages of viewing a diffraction grating at larger order?

If you are using a diffraction grating as a spectrometer you are likely to use high order, because you have a better resolution (as a result of larger dispersion??). But are there any disadvantage? I ...
3
votes
1answer
39 views

Why infrared light waves is visible through camera? [duplicate]

For example We know that some television manufacturers have the limited IR-based remotes which cannot be seen by our eyes directly but while playing when I just put my camera in front of my TV remote ...
1
vote
1answer
61 views

How do I convert lux to lumens

Overview... I'm a novice in the very basics of light physics and calculation between various units. I'm sure this is a very simple problem to those who know the process. And, before we continue, this ...
12
votes
2answers
3k views

Is true black possible?

Black is the absence of light because it absorbs light, but when we create black paint or black objects, light is always reflected, either in all directions in matte or smoothly in shiny black ...
5
votes
0answers
36 views

What's the size of the smallest possible CCD/CMOS pixel size?

For a given wavelength $\lambda$, is there a limit on the size of the sensor pixel, regardless of the optical equipment attached to the sensor?
5
votes
0answers
78 views

Why can I turn light red or blue by holding my finger up to it?

This is a difficult phenomenon to explain. Imagine you have an opaque object partially covering a very bright light source, for example, an object held up against the sky. The left hand diagram is ...
0
votes
3answers
76 views

Is the output of a laser pointer polarized or not?

How to verify it? Is a laser necessarily polarized? I have a laser pointer with wavelength 532nm in hand.
0
votes
1answer
26 views

Optical spectrometer

I am new on optical spectrometer, my particular interest is the spectrometer in which the deflection is produced by diffraction in a diffraction grating. But I can not find a good schematic and the ...
0
votes
0answers
25 views

Magneto Optical Kerr Effects

I have a few questions on MOKE setup. Firstly, why is calibration of the coils necessary? Is it to get a relationship between the voltage and the Magnetic field? Secondly, why do we have to normalise ...
2
votes
0answers
27 views

How accurately do Airy discs need to be superimposed in an optical interferometer to create fringes?

In an astronomical optical interferometer, what is the largest amount of error in the alignment of the Airy disks of point source star images from different arms of the interferometer that will still ...
7
votes
1answer
94 views

Viewing computer screen through 3D glasses, why the asymmetry?

I have 3D glasses made up of plastic. First case: When I hold front side of the 3D glasses (by this I mean that side on which light falls) in front of a computer screen, light coming from screen is ...
2
votes
0answers
15 views

How to deal with coma and oblique spherical aberration in a Czerny Turner configuration?

I am modelling my own spectrometer using Zemax when all of a sudden I've been told that: even if you manage to optimize the angles or positions of the grating and the mirrors, you won't get ...
1
vote
1answer
25 views

Apparent motion in a convex mirror

Why is it that if we look at the image of a person running with a constant velocity, in a convex mirror (for instance the rear view mirror of a car), the man's velocity seems to be accelerated?
2
votes
0answers
49 views

Is refraction of light a thermodynamic process?

Is refraction of light a thermodynamic process? Can it be explained by conservation of energy? If so, does temperature has an effect on refraction of light?
4
votes
1answer
82 views

Why don't extraordinary rays follow Snell's law?

I understand that ordinary ray (O-ray) and extra-ordinary ray (e-ray) have different refractive indices. This should mean O-ray and e-ray move with different velocities in a substance and they should ...
3
votes
1answer
52 views

What are the purposes of slits inside a spectrometer (Czerny-Turner)?

I am building a Raman spectrometer with a Czerny Turner configuration (with RamanPi). Why does the light source (A) appear to be converging into the entrance slit (B)? When a sample is excited by ...
1
vote
0answers
49 views

In the photon picture, how can light slow down and yet not be absorbed? [duplicate]

Many materials, such as glass, are transparent over some wavelength interval. In the photon picture, as far as I understand it, this is because there are no allowed transitions corresponding to the ...