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
12 views

Calculating the diameter of Jupiter through an image

I took an image of Jupiter through my 8" Dobsonian Telescope, attaching a DSLR and a 1.25" Barlow Lens where the eyepiece goes, as shown in this video: https://www.youtube.com/watch?v=reFxoF3XoaU ...
2
votes
2answers
28 views

Can AMO physics be applicable for space travel?

I know it sounds very stupid question. I am a Ph.D student currently working on the AMO physics (Quantum Optics). I recently saw articles about the Spacex, and I thought it is really amazing, and ...
2
votes
1answer
38 views

Does the Abbe limit hold for a single lens?

Let us say I have a single (converging lens) could I use the Abbe diffraction limit (for a microscope) to find its resolution or do I have to use the Rayleigh criterion. (i.e. Is the Abbe diffraction ...
0
votes
0answers
6 views

How does the area of illumination affect the numerical aperture / optical resolution of an optical system?

I have been reading an optics paper in which they designed a microscope with the following setup. A light source passes through a small pinhole, illuminates a sample, which then forms a diffraction ...
3
votes
0answers
35 views

Why don't the colors in an oil slick change as I walk past?

After it rains, I often see bands of color on the asphalt roads. This is usually explained as an thin film interference. Wikipedia has a picture of it which looks by inspection to be the same ...
2
votes
2answers
28 views

How does change in medium affect object distance/image distance?

Say,we have a container filled with a liquid of refractive index $7/5$ upto a height up $H$. There exists a plane glass mirror at the bottom of the container. Now if a fish were placed at a height of ...
1
vote
1answer
268 views

Why is an exciton only observed when we excite to the conduction band and not to other electronic level inside the bandgap?

Excitons can be observed when we excite electrons to the conduction band. I don't know about excitons being observed when we excite the electrons to an electronic level that would eventually be in ...
0
votes
0answers
18 views

EM waves: Circularly polarized light incident at Brewster angle

I am having problems in answering the following question: " Circularly polarized light is incident at the Brewster angle on a dielectric surface. With explanation, describe the polarization of the ...
45
votes
5answers
22k views

Why glass is transparent?

Once I asked this question from my teacher and he replied "because it passes light", "and why it passes light" I asked and he said "because it is transparent". Same question again, Why glass is ...
0
votes
0answers
20 views

Production of entangled photons by spontaneous down conversion [on hold]

I have found that the conditional uncertainty product of position and momentum of any one photon produced in the spontaneous parametric down conversion process using a gaussian pump beam decreases ...
1
vote
1answer
16 views

Michleson Interferometer fringe shift

I have a problem with interferometer fringe shift. I am learning it from my physics book. In the book, it is written, "As the L1 (Displacement of moveable mirror) is changed, the pattern of ...
0
votes
0answers
8 views

Binocular vs. monocular field of view in head-up displays

I've been reading about head-up displays in Wiki: Head-up display and understand that it works such that an image from an LCD screen (automotive) or from a cathode ray tube (aviation) is projected to ...
12
votes
3answers
1k views

What causes atoms to have their specific colors?

I understand that light (color) is part of the electromagnetic spectrum, and that it depends on what wavelengths are reflected/absorbed. Though what property of an individual atom gives it its color? ...
0
votes
1answer
605 views

Definition of pole of a spherical mirror

what can be a suitable definition to a pole of the spherical mirror. It cant be the geometrical center of a spherical mirror as if a mirror is cut then its pole does not change. moreover if a ...
0
votes
1answer
114 views

Refractive index and color

Does the color of an object have anything to do with its refractive index, and if so, what is the relation? I tried googling this and searching through the questions on stack exchange, but I haven't ...
3
votes
3answers
92 views

Why can't incoherent light be collimated as well as laser light (e.g. in a laser pointer)?

Why does a laser pointer contain a laser diode, and not just an LED? A laser pointer contains a laser diode, which essentially shines coherent light over a large angle, and a collimating lens, to ...
3
votes
2answers
219 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 ...
2
votes
2answers
365 views

Law of reflection for a moving mirror

An elementary fact that people learn about mirrors is the law of reflection, that the angle of incidence of a light beam striking the mirror (as measured with respect to a normal) equals the angle of ...
0
votes
2answers
171 views

Optical path difference

I have question about calculating optical path difference. $$\Delta L = \mathrm{(BC+CD)}\cdot n_2 - \textrm{BF}\cdot n_1$$ - why calculating path difference here we are subtracting $\mathrm{BF}$ ...
0
votes
0answers
29 views

how to solve this question? [on hold]

This is the question in my text : A monochromatic light of wavelength $\mathrm{600 \times 10^{-9}m}$ is used in a Young's double slit experiment. One of the slit is covered by a transparent sheet ...
0
votes
0answers
24 views

How to solve the following wave equation? [on hold]

We have paraxial beam propagating in a uniaxial anisotropic media. When such is the case wave can be divided into two orthogonal parts: Ordinary wave beam Extraordinary wave beam. The ordinary ...
0
votes
1answer
26 views

How black body absorbs light?

I learn that black body absorbs light, but couldn't get the mechanism behind it. I wish I could get help.
14
votes
3answers
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 ...
0
votes
0answers
33 views

Amplitude of unpolarized EM wave after a polarizer

The amplitude of a linearly polarized wave after a polarizer is $$E_1 = E_0\cos(\theta)$$ and the intensity is $$I_1 = I_0\cos^2(\theta)$$ Now for unpolarized light, the time averaged amplitude is ...
1
vote
2answers
117 views

How to calculate reflection profile of a beam shining onto a moving mirror?

I want to build a projector, where a beam of light is shining on to mirrors, placed at different angles, which are spinning fast enough to draw lines. The question is, how to calculate the needed ...
0
votes
1answer
24 views

Tilted and Misaligned Items in Optical Schemes

My scientific advisor has said me to find correct and concrete ray matrices (ABCD (2x2) or ABCDEFGHI (3x3) or ABCDEFGHIJKL (4x4)) corresponding to tilted and misaligned optical elements such as: ...
0
votes
2answers
46 views

Interference Pattern and dark lines

Two very narrow slits are spaced apart and are placed 35.0 cm from a screen. What is the distance between the first and second dark lines of the interference pattern when the slits are illuminated ...
10
votes
1answer
47 views

Glowing light around my shadow during sunrise

This morning I was jogging when the sun came rose. I was in the middle of wheat-fields and noticed that there was a glow around the upper part of body's shadow on the fields. At first I thought that ...
3
votes
0answers
24 views

Quantify shade-off and halo effect in phase contrast microscopy

Shade-off and halo effect introduce distortion to phase contrast images. I am trying to utilize these features to write a program which could identify spherical cells from (positive) phase contrast ...
3
votes
2answers
2k views

Why is the atmosphere transparent in the visible spectrum?

One of the great 'coincidences' in physics is that the Sun happens to shine most brightly at exactly the wavelengths our eyes can see; it's an easy explanation that our eyes evolved to make the most ...
21
votes
1answer
806 views

How can my window not scramble the image of my yard?

How can an image pass through a window if the atoms in the glass randomly emit photons in any direction? I've read that glass is transparent because the atoms don't readily adsorb visible light, so it ...
28
votes
3answers
4k views

Why aren't all objects transparent?

I know that for an object to be transparent, visible light must go through it undisturbed. In other words, if the light energy is sufficiently high to excite one of the electrons in the material, ...
1
vote
2answers
77 views

How come lenses alter the path of photons?

From what I know, photons are theorized particles and believed to be massless (just energy) and travel at the speed of light. How come a lens, which is an object made of atoms, can bend a light path? ...
3
votes
1answer
35 views

Does the angle of incidence change the refractive index?

I've been told if you plot a graph using the sine of the angle of incidence and the sine of the angle of transmission it should follow a linear regression $y = ax + b$. However, if you use certain ...
0
votes
0answers
17 views

Find the ratio of maximum intensity to minimum intensity [closed]

Question: Two coherent sources of intensity $10Wm^{-2}$ and $25Wm^{-2}$ inference to form fringes. Find the ratio of maximum intensityb to minimum intensity. Progress: ...
1
vote
1answer
23 views

What is meant by the point-source response of eye or telescope?

I have heard that a source is called unresolved if it is much smaller in angular size than the point-source response of the eye or telescope observing it. What is the meaning of point-source response ...
2
votes
2answers
139 views

What will be the effect of placing a light source very close to a photodiode?

What will be the effect of placing a photodiode really close to a laser source and what should be the appropriate distance between a light source and photodiode to get maximum output current?
0
votes
0answers
24 views

Is there a minimum population inversion necessary for lasing? [on hold]

Let's say I have a cavity built, with a lasing medium inside, positioned optimally. What are the conditions on the population inversion that must take place for lasing to occur?
2
votes
1answer
39 views

Does curving only the inner surface of a diving mask prevent blurred images?

Diving masks often have lenses built into the glass for divers who do not have perfect vision. The lenses in a diving mask faceplate often only have a curved surfaces on the inside glass. Why is this ...
1
vote
1answer
113 views

Maxwell Stress Tensor at material boundaries

I am trying to grasp the meaning of the Maxwell Stress tensor $T_i^j$ at material boundaries. Concretely, I am trying to calculate the force between two waveguides. The results are given in an article ...
2
votes
0answers
19 views

What is the relative importance of lens element quality in a multiple lens system? [on hold]

I tried grinding a custom lens out of acrylic glass (diameter 20mm, focal length 30mm). Not very surprisingly, the result is a quite poor quality lens. I think it mostly suffers from geometry and ...
6
votes
1answer
204 views

How would we see the earth if refraction of light was significantly stronger?

On worldbuilding.SE there is a question about the cosmological consequences of a world with super-high refraction and atmosphere opaqueness. I'm assuming the easiest way to minimally change the laws ...
7
votes
1answer
302 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?
3
votes
1answer
20 views

Is perfectly diffuse reflection entropy maximizing?

Suppose that I shine light on a surface and none of it will be absorbed or transmitted, and the spectrum doesn't change (so that all that's left to determine is the power reflected from the surface as ...
20
votes
5answers
8k views

Eyes open under water

Yesterday I looked underwater with my eyes open (and no goggles) and I realized I can't see anything clearly. Everything looks very, very blurry. My guess is that the eye needs direct contact with air ...
0
votes
1answer
29 views

Application of Snell's law for an extraordinary wave?

I have read [1] that when the light enters a birefringent material with optical axis perpendicular to the plane of incidence that the angle of refraction of the extraordinary wave can be found by ...
0
votes
1answer
18 views

Why is second harmonic Intensity periodic in coherent length?

Solving for the intensity of second harmonic generation we get that intensity is $sinc^2(\pi/2*L/L_{coherent})$. How is calculated that the intensity is periodic in L_{coherent} (coherent length, L ...
-1
votes
1answer
34 views

What is the theoretical maximum data transmission rate of an optical laser at 400nm and at 800nm, with optimal pulse width? [on hold]

I want to know what the highest possible data transfer is for visible light with regards to the frequency, disregarding noise. Using the shannon-hartley formula wasn't of much use, as it operates ...
2
votes
2answers
69 views

Is Huygens's Wave Theory still correct?

We have to study on details about Huygens's Wave Theory though we have Electromagnetic theory, quantum theory today. Is it still correct or not?
0
votes
1answer
50 views

What is the difference between a white object and a mirror in terms of heat absorption?

Will a white object be cooler than a mirror when exposed to direct sunlight? Or will it be the other way around? If mirrors bounce all visible light and some of the other elements of electromagnetic ...