Remember me

[ ]
[ ]
Guests: 23, Members: 1 ...
Plasma viewing forum.php

most ever online: 333
(Members: 3, Guests: 330) on 06 Jun : 15:15

Members: 3396
Newest member: ghilinta.daniel
Members Birthdays:
All today's birthdays', congrats!
Gagazet (25)
Chris Cristini (28)

Next birthdays
07/22 Reaching (32)
07/22 ryanshow (30)
07/23 Will (30)
If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.

Special Thanks To:
  • Aaron Holmes
  • Aaron Wheeler
  • Adam Horden
  • Alan Scrimgeour
  • Andre
  • Andrew Haynes
  • Anonymous000
  • asabase
  • Austin Weil
  • barney
  • Barry
  • Bert Hickman
  • Bill Kukowski
  • Blitzorn
  • Brandon Paradelas
  • Bruce Bowling
  • BubeeMike
  • Byong Park
  • Cesiumsponge
  • Chris F.
  • Chris Hooper
  • Corey Worthington
  • Derek Woodroffe
  • Dalus
  • Dan Strother
  • Daniel Davis
  • Daniel Uhrenholt
  • datasheetarchive
  • Dave Billington
  • Dave Marshall
  • David F.
  • Dennis Rogers
  • drelectrix
  • Dr. John Gudenas
  • Dr. Spark
  • E.TexasTesla
  • eastvoltresearch
  • Eirik Taylor
  • Erik Dyakov
  • Erlend^SE
  • Finn Hammer
  • Firebug24k
  • GalliumMan
  • Gary Peterson
  • George Slade
  • GhostNull
  • Gordon Mcknight
  • Graham Armitage
  • Grant
  • GreySoul
  • Henry H
  • IamSmooth
  • In memory of Leo Powning
  • Jacob Cash
  • James Howells
  • James Pawson
  • Jeff Greenfield
  • Jeff Thomas
  • Jesse Frost
  • Jim Mitchell
  • jlr134
  • Joe Mastroianni
  • John Forcina
  • John Oberg
  • John Willcutt
  • Jon Newcomb
  • klugesmith
  • Leslie Wright
  • Lutz Hoffman
  • Mads Barnkob
  • Martin King
  • Mats Karlsson
  • Matt Gibson
  • Matthew Guidry
  • mbd
  • Michael D'Angelo
  • Mikkel
  • mileswaldron
  • mister_rf
  • Neil Foster
  • Nick de Smith
  • Nick Soroka
  • nicklenorp
  • Nik
  • Norman Stanley
  • Patrick Coleman
  • Paul Brodie
  • Paul Jordan
  • Paul Montgomery
  • Ped
  • Peter Krogen
  • Peter Terren
  • PhilGood
  • Richard Feldman
  • Robert Bush
  • Royce Bailey
  • Scott Fusare
  • Scott Newman
  • smiffy
  • Stella
  • Steven Busic
  • Steve Conner
  • Steve Jones
  • Steve Ward
  • Sulaiman
  • Thomas Coyle
  • Thomas A. Wallace
  • Thomas W
  • Timo
  • Torch
  • Ulf Jonsson
  • vasil
  • Vaxian
  • vladi mazzilli
  • wastehl
  • Weston
  • William Kim
  • William N.
  • William Stehl
  • Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
4hv.org :: Forums :: Electromagnetic Radiation
<< Previous thread | Next thread >>   

CMOS camera geiger hack

Author Post
Wed Sep 02 2009, 07:24AM Print View
Registered Member #96
Joined: Thu Feb 09 2006, 05:37PM
Location: Republic of Guernsey
Posts: 3779
Hi all.

Update on my CMOS camera hack:- pyrolytic graphite works fine if split down, then sanded down to around 0.3mm thick.

I discovered that reducing the clock speed from 13.5 to 4 MHz increased the sensitivity by about a factor of three and allowed me to view individual particle interactions on my 'scope.

fwiw this is a B&Q camera, with the exposed chip surrounded with epoxy and a piece of PG installed about 1mm away from the chip.
The chip has damage that renders it unsuitable for use as a camera (large dead spots) that strangely enough doesen't show up on the geiger images.
Back to top
Proud Mary
Sun Sep 06 2009, 02:22AM
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4958
That's excellent Andre! You should write up a whole report about it in the projects section.

I expect the dead spots are not 'dead' but areas of reduced sensitivity, so that the higher detection efficiency of alphas is able to lift the signal above the noise floor to the point where it can be detected.

Back to top
Sun Mar 20 2011, 02:40PM
Registered Member #96
Joined: Thu Feb 09 2006, 05:37PM
Location: Republic of Guernsey
Posts: 3779
Sounds about right.
Sadly the camera stopped working about a month later, I don't know why but suspect moisture damage to the chip.
Was a gradual failure, the output stopped generating video but I could still see the signals if I biased output at +V, then it stopped entirely a week later.

Memo to self, next time use UV cure glue as it fully encapsulates the delicate interconnects.

Back to top
Adam Munich
Mon Mar 21 2011, 04:23AM
Registered Member #2893
Joined: Tue Jun 01 2010, 09:25PM
Location: Cali-forn. i. a.
Posts: 2236
I've tried this before actually with a webcam, and just so you know the radiation eventually causes more and more pixels to die until it's pretty much useless...
Back to top
Proud Mary
Mon Mar 21 2011, 09:59AM
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4958
A Google trawl for "CCD radiation damage" brings up a big hawl.

I found this one to be the most accessible to someone like me, who is unfamiliar with the field:

Radiation Damage in CCDs used as Particle Detectors
Back to top

Moderators: Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Bjørn, Dave Billington, Steve Conner, Wolfram, Kizmo, Mads Barnkob

Jump:     Back to top

Powered by e107 Forum System
Legal Information
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.