silicon PMTs

Soon your "RFID powder" can have gamma spectrometers onboard.

Cool, thanks! The dark count rate for the 850 nm ones is pretty bad.) (2.5 MHz.!) Hey and stock at DK for ~$50--60 each.

George H.

The Hamamatsu parts are a lot better for dark current, but may be a lot harder to get. We've been working with their 14160 parts and they work a lot better. Also, in modest quantities, they are cheaper, and in large quantity they are WAY cheaper, like $11 each.

Jon

Be carefull what parts you compare, size, fill factor etc. I do not think sensl and hamamatsu had different dark current when comparing similar situations. I found the low breakdown voltage of the sensl parts handy.

--
Uwe Bonnes                bon@elektron.ikp.physik.tu-darmstadt.de 

Institut fuer Kernphysik  Schlossgartenstrasse 9  64289 Darmstadt 

Maybe it's not so important to concentrate on the dark-count specs. Instead look at maximum output- current specs. E.g., for C-series: 6, 15 and 20mA for the 1, 3 and 6 mm sensor sizes. Think s/n.

--
 Thanks, 
    - Win

It's probably intended for consumer lidar, so it's probably dirt cheap in volume.

Depends. In imaging applications such as the SEM cathodoluminescence system I've been posting about, you need megahertz count rates to get a reasonabl e SNR at an acceptable frame rate, so the dark count rate isn't as much of an issue as in a photon-counting application. However, 2 MHz is a pretty ri diculous false count rate.

A minimally-acceptable image might be 300x300 pixels at an optical SNR of 1

0 dB. Gathering that in, say, 10 seconds requires 90,000*100/10 = 900k de tection events per second. Overcoming a 2-MHz false count rate would increa se the frame time by a factor of 10.

Cheers

Phil Hobbs

The wavelength is important. I'd like to do these correlated and then entangled photon experiments... down converted from ~400 nm so ~800 nm detectors.

George H.

Yeah Win, let me just say I've been reading a lot of correlated photon experiments papers written by physicists, and they have no idea about signal to noise... and say all sorts of stupid stuff. It bothers me.

George H.