Natural Science Forum / Physics / Optics / July 2008

Quick follow up.  I never did find 27.12MHz oscillators, but Mouser has
27.12MHz crystals in stock right now.  It says NON STANDARD VALUE so I'm
guessing they won't get more when the current stock runs out.
http://www.mouser.com/Search/ProductDetail ...

Naive individuals tend to associate infrared radiation with heat. This
is wrong. Let's say there are two beams of light, one is UV and the
other is IR. If the two beams have the same
photons-per-second-per-square-meter and are absorbed with equal

Hi, group
 I'm working on a CO2 fast axial flow design, and am running into
difficulties finding information on how others have built them.  I
plan on a device like the patent #4,672,620.  

Hello, I am computer science student and I have a question wrt GTD as
I am writing a computer program based on it.GTD allows us to use ray
tracing. I have been given a triangular mesh(object made up of
traingular facets) and I am supposed to apply ray tracing tehcniques

here is the motherload
http://shop.ebay.co.uk/merchant/405nm
laser light the sky at night
404nm

I have an ever-expanding folder of pdf documents, which are named as I would
reference them in a paper (Author1 AB, Author2 CD, ''Title', Journal (Vol)
No pp (year) ), but I'm wondering whether there is database software
available for the personal user (not a library or ...

Dear All, Would you please answer the following question?
If the small signal bandwidth(-3dB) (Cin=0.5pF)of TIA designed for
1.25Gbps application is only 700MHz,is this TIA OK for 1.25G PIN-TIA
application?If not,what is the problem caused by narrow bandwidth?

As homework, i should design a transimpedance amplifier (with opamp)
for photodetector's front end. I haven't any specification about
photodiode's characteristics, so i haven't any information about
pratical uses of this system. I can choose arbitrarily any photodiode

Sam, I need a schematic for a laser physics reliant ? got any?
Steve Roberts

A Spectra-Physics Model 165 argon ion laser (with excitor Model 265)
and/or a Spectra-Physics Model 164 (with no power supply) may be
available fo4 essentially the cost of shipping from Detroit, MI.  The
condition unknown on both but I suspect the power

Model OFB-20 is a portable and versatile Ytterbium fiber laser system
developed by GnW Laser (Woburn, MA; www.gnwLaser.com). The machine can
engrave on all metals with depth. It is also suited for all marking,
drilling, cutting and micro-processing applications. It is designed

I'm looking for books, articles, any information about the bend losses
in fibers. I'm  mostly looking information about multimode fibers, but
any information ( for example: formulas describing bend losses).  I
will be very thankful,  for titles, e-books or articles.

Hello Group,
I have a question to which some of you may know the answer.
Does glass with antireflection coating provide greater resistance
to scratching than pure glass?

Can anyone give me an idea of the best way to align mirrors to form a
cavity.  I am going to be giving this ago shortly and I hear that its
quite difficult.  The cavity is for an Nd:YAG laser...
Have any of you found any useful tricks that help you over the yrs?

So I'm trying http://www.news.astraweb.com/.  $10 for 25 GB no expiration.
Someone here? suggested it.  25 GB should be enough for several lifetimes
of text-only usenet access.
But I can't get alt.lasers to work properly.  Is anyone here using