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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Is it possible to make glasses that make everything brighter, but do not magnify or focus?

Corrective glasses are usually intended to help focus light on your retina. Supposing I had good vision already, but simply wanted more light, could I make glasses that would send more light into my ...
2
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0answers
132 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
38 views

Determining actual dimensions of an object from it's image [on hold]

I have to make an ios app that predicts the actual size (height, waist, chest etc) of a person based on his photo and then suggest clothes of that size. I just want ideas as to how the actual ...
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0answers
24 views

Why we see a distant object more closer from us with a telescope?

The side magnification in the image obtained by a telescope its always less than 1, then, Why we see a distant object more closer from us?
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0answers
37 views

What exactly is 'crosses of light'? [on hold]

when i looked two bulbs through my window it appeared as luminous crosses.i also took photoes.what exactly is this?
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1answer
119 views

Diffraction and $k$-space

Regarding diffraction I am a little bit lost reading about reciprocal space and the space of $k$'s. As I understand it the Fourier relationship between a wavepacket $\Psi(\vec r,t)$ and the complex ...
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1answer
46 views

Is a non reflective display possible?

Can you think of a surface, that emits light, but doesn't reflect any light coming from outside (absorbs it)? Under what circumstances would this work?
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0answers
44 views

Thermal contact burn [on hold]

My client fell asleep in a bus stop leaning back against 3/16 in clear plate glass For an hour with a tee shirt on. It was about 80 degrees Fahrenheit and the sun was shinning on the glass. He woke up ...
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0answers
25 views

Conseptual Questions on Optics [on hold]

a man of height h is standing in centre of a room in which a mirror is hanging to the opposite wall the height of the mirror required to see the full height of backside wall in the mirror is
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29 views

Laser diode input and output power ratio [on hold]

I am a photo technician working in photographic labs to repair printing machines. I need technical help from you and from your technical team, as I want to know some basic information. May be it will ...
47
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3answers
3k views

How to measure the wavelength of a laser pointer?

I'm working on something and I need to know the wavelength of the laser pointer that I'm using. Can you suggest me a way, using some optics formulae, or anything else to calculate the wavelength?
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1answer
31 views

In a lens the image formed by the first surface serves as the object for the second surface.What is the reason?

When deriving the lens maker's equation I faced the problem of understanding the logic behind this reasoning "image formed by the first surface of a lens serves as the object for the second surface."
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1answer
30 views

Determining path of light through a nanolens

In the case of light passing through stacked liquids, we can use a ray approximation of the path of light to determine the path taken through each layer of liquid using Snell's law. From all the ...
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0answers
9 views

Optimal wavelength for low IR attenuation under normal atmospheric conditions?

I can't find any good data about the transmit attenuation of infrared light in the atmosphere transmitted horizontally (there is a bunch of stuff detailing penetration of radiation from space, but ...
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0answers
45 views

Re-reflecting in HUD optics

Simple HUD optics design can be described with below image. (source : http://www.mikesflightdeck.com/hud/head_up_displays.html) As you can see, if combiner and colimating lens(after fold mirror) ...
2
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1answer
151 views

Optics for projecting OLED screen DLP style

I just bought a small OLED screen and was wondering is it possible to make a screen surface a little bit bigger ( 2x ) by projecting it through some optics on translucent surface. It reminds me of ...
2
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0answers
24 views

How much UV light do we have on the ground? [on hold]

We cannot see it. But suppose each UV photon is replaced by a red light photon, does it make the world look as bright as it is just before the sunrise?
3
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1answer
95 views

Why do we use the index of refraction for yellow light?

When we do problems with optics and refraction, we’re usually given a set of indices of refraction to work with; for example, the index of refraction in air is about 1.00, the index of refraction in ...
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1answer
50 views

Do parallel rays reflecting at a mirror not intersect at one point? [closed]

Let's take a concave mirror with $CP$ as its principal axis. Let's assume that a parallel ray $p$ to $CP$ reflects at $A$ to pass through the focal point $F$. Then, $\angle CAF=\angle ACF$, which ...
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2answers
179 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 ...
2
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4answers
477 views
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1answer
38 views

Brightness of light sources

I would like to know what determines the brightness of light.I'm confused,After hours of reading i got these definitions mixed up i need to link them together : Light intensity Brightness of light ...
0
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2answers
218 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 ...
0
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2answers
106 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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3answers
44 views

Green light on red article

When white light falls on an object the body absorbs all colors of light and reflects some colors of light which we see the object to be.For eg.A red ball reflects red color and absorbs the rest ...
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0answers
44 views

False sunset and false sunrise time estimation

False sunset and false sunrise are described . Here is a sample day rise and set time according to AccuWheather site and calculated value of sunrise and sunset in my country. Could you please help ...
2
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1answer
56 views

What operation does a beam splitter apply?

What is the unitary matrix equivalent to the operation of a beam splitter? I'm asking because I've seen different matrices used and was wondering if the term is just ambiguous or if there's an agreed ...
3
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1answer
54 views

Why is responsivity quoted as a figure of merit?

Lately I have been investigating the physics literature on proposed photosensitive electronic devices made of graphene. Often I see responsivity values quoted as if they suppossed to impress, and ...
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1answer
18 views

Which features effect on the Reflection of things?

I'm working on something and I need to find a wire that doesn't reflect well. so, I know one feature is the color of the wire to decrease the reflection. But what other features effect on the ...
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0answers
31 views

Why does being unable to collect all emitted light from a source lead to the diffraction limit?

My optics textbook (Hecht & Zajac) says the following: Most commonly, the function of an optical device is to collect and reshape a portion of the incident wavefront, often with the ultimate ...
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4answers
3k views

Do eyeballs exhibit chromatic aberration?

Fairly straightforward question. If not, why not? I suspect that if they do, it is not perceived due to the regions of highest dispersion being in one's region of lowest visual acuity.
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1answer
70 views

How to extract depth of a pixel from an image?

I'll have a few pictures that show the same scene, but only a few things move around a little bit. Now I don't have an information about any size in real life but I'd like to extract a scaling factor ...
2
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2answers
31 views

Is it possible to calculate the relative abundances of elements in the sun based on its line spectrum using a common lab spectroscope?

There are many problems that I feel would hinder the process: atmospheric noise, light pollution etc. Let's assume that I bypass these problems and get an accurate emission line spectrum on the ...
4
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5answers
204 views

What about a surface determines its color?

Light falls on a surface. Some wavelengths get absorbed. The other are reflected. The reflected ones are the colors that we perceive to be of the surface. What is the property that determines, what ...
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0answers
27 views

Why does not the optical fiber break? [duplicate]

Glass is a very fragile object. So why does not the optical fiber break? Everytime I take them, I am worried about this problem.
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1answer
52 views

How can we see objects that are so far away? [duplicate]

The HUDF used to be the deepest image of the universe ever taken by the Hubble telescope, the furthest star in this image is 59000 light years away. The star in question: Now Imagine a light ...
2
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1answer
115 views

Laser Transverse/Longitudnal Modes

When we say Laser transverse modes. Is that mean what we will get at the output spot of laser beam ? secondly In practice , what TEM01 or TEMnm means ?
2
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2answers
418 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
36 views

Is crystal diffraction actually diffraction?

It seems like a very common model that is taught in schools for crystal diffraction is that there is an incident plane wave of light on a crystal lattice, and each atom in the lattice scatters the ...
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1answer
25 views

Optics Spatial Resolution

what does it mean to have a micrometer spatial resolution. Does it mean the resolution is 1 micrometer or can be 2,3,4,.... etc.? I do not understand it. Is there anybody?
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2answers
117 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 ...
4
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4answers
857 views

Does optical fiber preserve the angles of incoming light?

I am reading up on optical fibers and there's one thing I haven't understood yet: Does an optical fiber preserve the angles of incoming light? For example, if we light two LEDs in front of an ...
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0answers
9 views

Why is a time-varying phase equivalent to a spectral shear?

A spectral shear of an optical pulse can be achieved by inserting a time-varying electro-opto (EO) crystal in the beam path to modulate the phase of the pulse. How is this spectral shear achieved ...
2
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1answer
76 views

How do solar cells increase the lifespan of the Sun?

While reading "Physics of Solar Cells" by Würfel, I came across an amusing statement: An interesting aspect arises if we had to pay for solar energy, but could also get a refund for energy ...
4
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2answers
326 views

Why are non-linear optics called non-linear?

Looking at the wikipedia article on nonlinear optics you can see a huge list of frequency mixing (or multi-photon) processes. What makes these different from single-photon interactions? More ...
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0answers
11 views

Coordinate Transformation across different media

I have an arrangement that is as follows : (1) inner cylinder(radius r1) filled with water (2) outer cylinder(concentric, radius r2>r1) made of glass I have a sensor S1 at radius r(r1) at angle beta. ...
3
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5answers
4k views

Eye sensitivity & Danger signal [duplicate]

Why are danger signal in red, when the eye is most sensitive to yellow-green? You can check luminosity function for more details...
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2answers
2k views

Why doesn't my pinhole camera work?

We all know that light travels in straight a line, which can be proved by pinhole imaging as in the picture shown : But when I'm doing this little experiment with an apple, no matter how I change ...
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1answer
34 views

Is there a formula to calculate the deviated angle of a ray passing through a prism?

I'm assuming the angle of incidence to be the number of degrees from a perpendicular line on the side of a prism the ray starts passing through... I'm trying to figure out the angle the ray would be ...
0
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1answer
51 views

Why isn't this calculation of the energy of a light wave correct? [closed]

I'm trying to calculate the energy $J(T)$ that monochromatic light wave with electric field strength $E(T)$ supplies to unit electric charge over period of time $T$: $J(T)=\int\limits ...