There are a lot of problems associated optics at cryogenic temperatures. I found in my designs experience that reflective optics are the prefered optical system. It is the easiest to design and fabricate.
Check Edmund Scientific for surplus lenses: For that application you need a very fast lens if you wish to project it onto a projection screen of the size that you want. The computer CRT needs to be a special high intensity version to get sufficient light to the screen, as well.
This is a large telescope and requires an indepth knowledge of the mechanics as well as the optics. This is best left to the experienced telescope designers like Perkin Elmer or Bauch & Lomb.
Hi.......Index matching and coupling between the optical coponents become very important in achiving near zero interfacing losses and damage.
The NA into the Fiber should match or be greater than the NA of the Gausian beam input.
The NA(fiber)=sqrt[N(cladding)-N(core)]. Index matching is...
I'm sorry I didn't get back to you earlier, but I'm working with rectangular cisterns that are 3 1/2" thick concrete and buried with 8 feet of soil. Your equation were helpful and made me research further to find the proper solution, which I am still working on.
Thanks Jerre
Consider Reflective wrap which is extremely efficient for pipe insullation. Insulators retards the heat flow they do not dissapate it well. This mean that the heat will eventially bring the temperature of the insullator to that of the pipe or reverse depending which is hotter. Aluminum maybe a...
This experiment is simular to Michaelson experment for measuring the speed of light. He is the one who is responsible for being first to measure the speed of light, but he used a an optical prism intead of a water filled coke bottle. The speed of light in air and a vacuum, with an index of...
I am building an underground water heat transfer system. In order to calculate the heat capacity of the system, I need the heat exchange rate (BTU's per hour) between the red clay soil(typical of North Georgia), which is at 56 degree F and the water in the concrete cistern. Help, please...