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It turns out that one photon states of the electromagnetic field can be written in a way such that the state "propagates" fulfilling Maxwell's equations. This is an exact model as I discuss this in more detail in my answer here. So we begin with a one-photon Fock state of the quantized electromagnetic field. Let's keep our discussion to one mode, so one ...


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For many materials the change in refractive index over the range of visible wavelengths isn't huge, so it's not a bad approximation to take a single value. The range of visible wavelengths is from about 400nm to 700nm, so the middle wavelength is 550nm. As it happens, the sodium D lines are not far from this, at 589nm, and since they are bright and easy to ...


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If the two sides of the prism are parallel, then the ray will exit the prism at the same angle it entered, just offset. If you need the offset, or the faces are not parallel, then you need to calculate the exact path the ray takes through the material. That requires knowing the index of refraction for the material. If you have that, then you can use ...


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Actually, people have answered the question you seem to have meant, rather than the question you've asked. When a change in index of refraction causes a change in the direction of a ray of light, this is refraction. It is not dispersion, and has nothing (immediately) to do with dispersive mediums. Dispersion (rays of different wavelengths being refracted ...


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$q$ is a parameter which describes the distribution of a Gaussian beam with respect to the optical axis. You can think of the $q$ parameter as a bundle (a 'pencil' in Born & Wolf parlance) of optical rays, each described by its own position $r_i$ and slope $\theta_i$. So, using the transformation on the $q$ parameter that you describe is all you need ...


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first the speed of light is related to the permittivity and permeability of the medium. changing either one of those values changes the speed of light. copper has different values then free space. the speed of light through copper is 2/3rds that of free space. about 1 foot per nanosecond. slightly faster in aluminum, slower in iron. this can be measured ...


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Light is described well by the classical electromagnetic theory and Maxwell's equations. In this framework, the classical one, the speed of light is constant in vacuum. When light impinges on transparent materials, its speed, classically changes, and this is measured with the index of refraction of the material: where c is the velocity of light in vacuum ...


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Speed of light is constant. But in some substances , still transparent , light is absorbed and retransmitted ( with the same properties ) , spending some time. With not well transparent material, things are more complex. Anyway, between 2 obstacles, it's the vacuum and the speed remains constant and maximum. How many are retransmitted and the specific ...


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the way I see it is that the recording of an interference pattern creates a diffraction grating pattern on the plate. This is not a pattern of just straight lines, the reflected light from the object has created a unique pattern. When light passes through this recorded interference grating it behaves like any wave hitting a wall with small gaps. At the other ...


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I have been reaserching some more, and what I have found is something about waves in dispersive media. (The wave speed depends on the frequency of the wave). Source: (http://www.acs.psu.edu/drussell/Demos/Dispersion/dispersion.html) Apparently when the wave is traveling with a frequency close to the resonans frequency $n$ gets smaller than $1$. But only the ...



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