Natural Science Forum / Physics / Optics

Does the output wavefront phase of a diode laser change with power
output (over a very small time frame)?  I am considering the situation
where the laser is modulated at a MHz or greater rate.  The reason for
the question is that if the phase does change (perhaps due to

How much costs a cheap SEM for a private customer. This microscope
should be able to supply 10.000 magnifications at least.

Ho to everyone.
I've a problem with a laser-fiber coupler.
I'm using a polarization mantaining fiber to redirect a He-Ne laser
beam to a desired direction, without moving the laser. Considering

Hi to everyone.
I've a problem with a laser-fiber coupler.
I'm using a polarization mantaining fiber to redirect a He-Ne laser
beam to a desired direction, without moving the laser. Considering

I own a wickedlasers CORE laser pointer. I've totally blown away by it
(it's incredibly bright for a 5mw). Anyhow, I was using it recently
and something seemed out of place. After laying the laser against a
wall and rolling it while it was activated I could easily tell that

I remember reading statements about how "viewers" prefer images with
a horizontal field of view not beyond X, with X somewhere around 120
degrees. This was not in academic sources, however, but rather in
photography manuals trying to explain why extreme wide angle images

I picked up one of the many Coherent FAP-I modules on ebay. Specs are
40W @ 808nm at 53amps, 2.2v. Threshold is 10-13 amps. Pretty neat
module. Uses a Coherent FAP800 module sitting on a hear spreader
through 4 TECs into the gold plated copper case. The FAP has a small

Total newbee here - looking for either a new or refurb used high power
student scope - a couple questions if I may:
1. Generally, what should I be looking for in a scope?
2. What are the best brands?