6

Yes, other electromagnetic radiation can be focused, and routinely is. Basically, everything up to x-rays can be focused relatively easily. Once you get to energies so high that they go right thru most material, using these materials to focus such rays gets tricky or impossible. For example, I don't think we know of a way to focus gamma rays. On a cosmic ...


6

You might be interested to learn that not only are there microwave (and IR, and X-ray ... ) lasers, but that some of these "devices" can even occur naturally in gas nebulae in space. From the wikipedia article on Megamasers, A megamaser is a type of astrophysical maser, which is a naturally occurring source of stimulated spectral line emission. ...


5

Briefly: The way to distinguish your signal from any others (and incidentally get a massive gain in signal to noise ratio) is to use modulation. The simplest modulation scheme just turns the laser on and off very quickly (a few MHz) and your detection circuit (synchronized with the switching of the laser) ADDs detected signal when the laser is on, and ...


3

If a model does not reflect reality, the model is not accurate enough for that situation. Consider some of the minutia in the workings of light. First an alternate model for the fiber: As light passes through, some of it passes straight through, some is "absorbed." (quotes because I suggest including reflection and refraction in here as well as ...


3

If you increase the length of the fibre, you will get more reasonable results. The losses -in my mind- need to be distributed along the entire length of the fiber . Currently, you seem to model a very small portion of the fiber, and as such you have a very small area that need to transfer a seemingly small amount of energy. However, if that energy is going ...


2

I would just like to add, in addition to the other answers regarding the EM spectrum, that anything that follows the wave equation can be focused because all of the principles of constructive and deconstructive superposition apply. Things outside the EM spectrum that follow the wave formula include pressure waves (when focused, commonly referred to as ...


2

From the comment of @Dan and the linked Wikipedia article on masers: When the laser was developed, Townes and Schawlow and their colleagues at Bell Labs pushed the use of the term optical maser, but this was largely abandoned in favor of laser, coined by their rival Gordon Gould. In modern usage, devices that emit in the X-ray through infrared portions of ...


2

You could use a slab of glass or other transparent medium with a different refractive index then air. The slab should have two surfaces which are as parallel as possible and be mounted on a two axis gimbal. Namely the more you tilt the slab in any direction relative to axis of the beam the more the beam will shift in that direction, while maintaining the ...


1

Your assumption on temperature increase is flawed You can't convert watts to temperature directly unless the object is perfectly insulated and the application of heat has a limited time. The equation from your link would result in a temperature increase directly proportional to time, increasing forever. Temperature is a measure of "heat content," ...


1

After the exchange of comments, (more specifically) that the glass is transparent, my "guess" is the following: You state that the signal power loss is in the order of 1 W. Assuming the measurement system before and after can accurately measure the energy difference, this power drop can be attributed to the following things: increasing the energy ...


1

Here is an incomplete list of laser-based additive manufacturing, based on my comment. I might expand on it later: Selective laser melting/sintering (SLM/SLS): a laser beam melts/sinters a layer of powder at the desired spots, after solidification, a new layer is added and the process starts over. Stereolitography: basically the same as SLM, but instead of ...


1

U can use a mirror for feedback of the projected image and a SLR as in cameras (a piece of glass at an 45` angle to measure the difference between projected and image onthe screen and approp. adjust the focus.


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