Natural Science Forum / Physics / Optics / December 2006

I'm a grad student at UCSD working on automation of tomograpy in high
voltage TEMs. I think that some sort of computation model of the
microscope would useful - I imagine a piece of software that shows a 3D
rendering of where the stage and beam are and the way the beam is going

We need to lock onto one side of a sharp but moving resonance similar to
a Fabry-Perot dip. Sharp meaning around 10pm. Long story short, when
scooting the TEC via a ADN8831 chip it's tough to achieve regulation
without overshoot. IOW tuning the PID loop is a bear and the locking

Read this article (www.zeiss.de/C12567A100537AB9/allBySubject/FramedNews3).
It's like the very early days of semi-conductor, you just don't know what's
gonna happen next.  Welcome to the future.
Thanks,

I'm looking for a source for good quality, stock, glass, long, right
angle prisms.  By "long", I mean such that the length or "C" dimension
(as usually shown in catalogues) is 50mm or more, but the "A" dimension
(the legs of the right triangle) are only 15mm to 25mm, maybe up to

I am working with a group that is developing a  consumer medical
product based on mid IR. We need to make a "window" that transmits  in
the mid IR (wavelength 2.8-3.8) . Does anyone know what would be a low
cost material? What are the advantages/disadvantages of teflon or

Why you shouldn't give engineers time to themselves over the holidays...
http://www.die4laser.com/CO2pics/index.html

I am trying to modulate the refractive index of photonic crystal by
photoexcitation. What material should I use to get the largest change
in refractive index. Refractive index of what material would be most
sensitive to photoexcitation?

I am designing a confocal laser-induced fluorescence microscopy for
single molecules research. The fluorescence is in the visible
region.(500-600nm).
I tried to use the APD (SPCM-AQR-13, PerkinElmer)as the detector.

I forgot who it was..  Was it you Time Lord?

For a stupid short circuit, my cheap red laser module (chinese red about
80mw) is now an expensive led diode.
I'm searching for a laser diode in replacement. On the small case i can read

A device called a megalethoscope was featured on the Antiques Road Show
tonight. There was no serious description given. Google and Wickipedia
searches were also not very fruitful. The best they came up was that the
device used a large lens for viewing a print and gave some kind of ...

It was a big surprise when I put a small green hologram picture ---
some boxes and triangles -- into one of my Episkops and entlarged it
from some 8 by 10 cm up to round 90 by 100 cm. ; the surprise was that
around the picture also was pictured a wooden frame only visible when

I am unsure if this is the wrong group to ask, but I figured I will
throw out the question and hopefully someone can give me some guidance.
I would like to use a 2 axis scanner to draw approximately 4-5 large
"X" on the ceiling of an office. The X's are corresponding for specific

to Lostgallifreyan
what was the name of the software you mentioned in the past that you use for
tech. design drawings? I seem to remember it was architectural software (or
something like that) and you scale it for smaller objects.

I have the following problem with a Pockels cell from Conoptics (model
350-80), which we are using for two-photon microscopy (with a Mai Tai
femtosecond laser).
During a continuous frame scan with the microscope, fluorescence