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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Scattering of strong non-resonant light by cesium vapor

can anybody provide good references (research papers, books,,reviews, recent...) about a VERY strong NON-resonant light scattering from a cesium atomic cloud/vapor? (The light should be capable of ...
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62 views

Higher order multipolar second harmonic generation in centrosymmetric materials

As is pointed in this question, second harmonic generation is forbidden in the bulk of the materials possessing centrosymmetry. In some papers it is said that in the dipolar approximation the SHG ...
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42 views

Why can one see the outline of a white sheet of paper kept on another white sheet of paper?

Why can you see the outline of an object of a color that is in front of another object of the same color.
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48 views

Resonant vs. Non-resonant Raman

What does it mean to say that the conventional Raman effect is non-resonant? And, how/why does resonant Raman give a stronger signal than the non-resonant type?
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1answer
48 views

How to calculate the colour a human eye sees when looking at a light spectrum?

I have to do a presentation about colourants in Chemistry class (grade 12, advanced) and want to write a program that calculates and visualizes the colours of some simple molecules. What I need is ...
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19 views

Diffraction from a single slit experiment and Heisenberg's uncertainty principle [duplicate]

Practically how to separated between Fraunhofer and Fresnel diffraction? Do all diffraction fringes from single slit have same peaks? Why?
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2answers
44 views

Intuitive picture of diffraction without fictitious secondary wavelet

This question has been asked in a similar way but no satisfactory answers came up. Huygen's principle relies on the fact that if we consider an aperture, every element dS on the surface of the ...
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1answer
157 views

Solution of the wave equation [closed]

I am dealing with the solution of the wave equation in two different cases represented in figure by Case A and Case B. The two figures were obtained by shining a slab with an incident wave coming from ...
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33 views

Microscopy: aperture matching and Huygen's principle

I have repeatedly read that the maximum spatial resolution of a microscope occurs when the aperture of the objective and condenser are the same. However, I don't understand why. The resolution is ...
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2answers
66 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 ...
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1answer
23 views

An image in movement viewed by different cameras [closed]

Why in the image the string looks like is in two places at the same time, what is the optical reason or is it because of how cameras work?
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3answers
52 views

Frequency dependence of the speed of light in air

According to this link, the speed of light of different colors in a medium should be different. But if the refractive index of light in air is 1 then this means that the speed of light in air and ...
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24 views

What is the minimum required length of mirror to view full object if the mirror is convex?

i want to find the Radius of curvature of a convex mirror. i have all the factors to calculate except for image height of an object and image distane. so i can find the image height of an object from ...
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Mie's scattering Theory Problem

Is Mie's theory which describes the scattering of EM wave off sphere , possible to extend to spheroidal ? object or arbitrary shape with finite series expression ? I tried to replace the radial ...
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1answer
59 views

Is near point defined for a myopic eye and far point defined for a hypermetropic eye?

I learnt about far Point of a myopic eye and near point of a hypermetropic eye. But I am confused about the above question. And if near point is defined for a myopic eye and far point defined for a ...
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4answers
192 views

Double slit experiment collimating lens?

In some appratus for the Young's double slit experiment a collimating lens is used infront of the double slits, meaning plane wavefronts hit the double slits. But why do we need/want plane wavefronts ...
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5answers
201 views

White, is it a colour or absence of colours?

Our chemistry sir and we had an argument today at the lab, he says that white actually is not a colour, it is the abscence of colour, but we say that it is a colour and we gave the following point to ...
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1answer
298 views

Diffraction Pattern on LCD Screen

I was up late working with my red LED headlamp on and when I was looking at the black part of my LCD (Apple Retina Macbook Pro) screen I noticed this interesting diffraction pattern. I'm confused ...
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18 views

What is the transfer function in fft beam propagation for unpolarized light?

What is the transfer function in fft beam propagation for unpolarized light ? How to construct the fft beam propagation ? This is for homework. For coherent light the beam propagation is E(x,z) ...
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34 views

Laser travelling through a radially graded index of refraction

A laser beam propagates through a region whose refractive index varies as $\mu=\mu_0(\frac{r}{r_0})$. At a distance of R the beam makes an angle of 30° with the normal. Find the minimum seperation ...
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73 views

How many foci does a converging or diverging lens have?

I thought this was a simple question but can't seem to find a direct answer. In ray diagrams with a converging or diverging lens, we always draw F (the focal length) on both sides of the lens. But ...
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2answers
414 views

How can we redirect light from any direction to one direction

Not just focused light. I mean whenever light come from sideway or any angle. What device it called to refract light from any angle to one angle
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1answer
120 views

How do photons carry information?

In cosmology it's frequently said that photons from the early universe carry information from that time. However, wouldn't they also carry data from later interactions? How do we differentiate ...
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92 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 ...
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16 views

Why are certain opaque objects so biased?

Why is it that most of the opaque objects only block em waves in the visible spectrum but fail to block waves with frequency higher and(or) lower than the visible spectrum?
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1answer
69 views

How does a laser emit light in a coherent state?

Lasers work by stimulated emission of atomic transitions. Stimulated emission produces two photons which, because the particle number is well-defined, projects the field into a Fock state. However, it ...
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2answers
340 views

Why does a circle of light appear when I shine a laser pointer at a wire? [duplicate]

When I point a laser at a wire , a circle of light appears on a wall behind it . why this happens. What is the circle of light and why does it appear? Could anyone give some tips on what I should ...
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1answer
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Why zone-plate photography is not monochromatic?

Zone-plate photography produces somewhat "blurry" photos. However, according to Fresnel's equation, I'd expect the resulting photos to be somewhat monochromatic, due to the dependence between $r,f$ ...
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63 views

Why grating is an essential part of a monochromator?

From looking at these two images, it appears that the dispersed "rays" of the reflected light could be manipulated just as well if the reflecting mirror would be turned to a fixed angle. So why is ...
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Optics Network NEED good Reference or TEXT

I am using Optical Networks: A Practical Perspective, 3rd Edition (Amazon link) as a reference for studying optics network. The main focus of the course is rather on the layer, data, and protocol side ...
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1answer
238 views

Optics problem: Determining the new focal length when changing from film to CCD detector [closed]

An older camera has a lens with a focal length of 50mm and uses 34-mm-wide film to record its images. Using this camera, a photographer takes a picture of the Golden Gate Bridge that completely ...
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19 views

Making sense of sinogram of perspex block in air

I'm confused trying to visualize what happened exactly during this experiment: Setup with a laser and a photo diode on the opposite side. A perspex block (2x2cm) in between. Take 200 measurements ...
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74 views

Is possible carry light using a rectangular mirroned tube? [closed]

I'm newbie and I want know if Is possible to carry light using a rectangular mirroned tube and create a illumination system with this principle.? I think is possible using schemas with mirrored ...
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59 views

Reflection and refraction of light [duplicate]

When a light ray strikes an interface a part of it gets reflected, a part of it gets absorbed while another part gets refracted. Why does light reflect? Why does it refract?
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1answer
73 views

Lasers : Threshold Pump Power for Laser Oscillation [closed]

I was working my way through some basic laser problems , when I cam across this one : Consider the ruby laser for which we have the following values of the various parameters: $N =$ $1.6$ x ...
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1answer
37 views

Ray diagram for refraction

I'm having trouble finding out any errors in a ray diagram. The question is as follows: A ray of light falls normally on the curved face of a semi-circular plastic block, it hits the horizontal ...
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1answer
67 views

What is a lineshape function $g(\omega_0)$ in a Laser?

I am a newbie to the world of lasers and was working my way through some basic problems, when I encountered this one: Optical Electronics, A.K. Ghatak and K. Thyagarajan (Cambridge University ...
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79 views

geometrical optics

I doing an experiment now. My structure has 700nm periodicity. The surface of the unit structure is sloped at 45 degrees from the normal incidence angle. My laser is 500 nm. I can expect there ...
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3answers
98 views

Two mirrors paradox revisited

If I connect a video camera to a screen, so that whatever is seen by my camera appears on the screen, what do I see when I point it towards the screen itself? Is it, in terms of optics, this ...
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52 views

What is the total reflectivity/transmissivity of a pack of a semi-transparent glass sheets [closed]

Consider a pack of $N$ layered semi-transparent parallel glass sheets (like a 'cake'), each having the reflectivity coefficient and thickness $(r_k, d_k)$ for $k=1 \dots N$. Consider a light beam of ...
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54 views

Intensity of waves in single-slit diffraction

So I am trying to determine the relation between intensities of waves in single slit diffraction. Since I am pretty new to this topic, I couldn't find a way how to calculate the ratio between the ...
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1answer
78 views

Is lasering some natural phenomenon soemwhere?

Laser is actually the simplest kind of light, from a physical point of view. Many people think it is some rocket science simply because it is not natural but takes some human efforts to create. So, ...
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49 views

Is there a correct yet more compact way to write these equations?

I've got the following equation which denotes the total absorbance $A$ as determined by the sum of the absorbances of individual molecules: \begin{equation} A(\nu,c_{1},...,c_{n}) = \sum_{mol=1}^{n} ...
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37 views

If any, what would be the ideal modulation frequency for a phase-sensitive light sensing experiment in a non-dark environment?

I have constructed some equipment for sensing a beam of light. The equipment is enclosed in a rudimentary darkbox to block out the majority of the ambient room lighting, but is still partially ...
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2answers
117 views

Why the light bent towards the normal when they pass from rarer medium to denser medium?

Whenever the light rays are entering the rarer to denser medium they bend toward the normal. Then why the rays choose the path toward the normal? Why it cannot choose the path away form the normal?
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37 views

Does the color of refractive medium affects the color of refracted light?

Imagine if I have a red colored prism that splits white light ray into its seven components, would the red component be affected by the red color of the glass material of the prism in any which way? I ...
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1answer
58 views

How can diffraction happen in the Hubble Telescope?

I've seen people talking about the angular resolution of the HST is, if using Rayleigh's criterion, equal to: $$\theta = 1.220 \frac{\lambda}{D}$$ My question is, since the diameter of the HST $D$ ...
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1answer
50 views

How to project anything in medium(air) like projection in wall, as in a free medium [duplicate]

I just go through books and the internet. But I didn't get my answer that, can I project light in the middle of the air, or wherever we want, not only on wall. I found neon lasers but it also didn't ...
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23 views

scintillation of U/HE cosmic rays in snowflakes

Suppose there is a U/HE, a snowflake, and a human observer. What range of energies would produce visible effects? What would the reaction cross section look like? I don't know enough about the ...
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1answer
42 views

What is the difference between the Franz-Keldysh effect and free carrier absorption?

What is the difference between the Franz-Keldysh effect and free carrier absorption? My first guess to this is that the Franz-Keldysh effect involves a bandgap potential of non-zero volts D.C. while ...