Geiger counter app, kinda cool..

[scoson]

I just installed this and it appears to not have a calibration setting for the V yet but still kind of cool, may eventually work..

Turn your Android device's camera into a Geiger counter with DARPA-funded app

Sorry if I should have put it way up in app forum..

 

[Unforgiven]

I can move it for you if you would like.

 

[scoson]

Yes please

 

[Unforgiven]

I've moved this to the Android Applications forum at your request.

 

[chrlswltrs]

While this app does sound intriguing, I do not believe it is at all possible. There is no way a camera can detect radiation of any type. It requires completely different hardware and sensors.

I am saying this because I worked in the nuclear field for several years, and was personally responsible for conduction radiation surveys and controlling radioactive material. I have extensive knowledge of radiation and how it is detected, and currently cell phones do not have the required hardware. Someday they might have the hardware in specially designed phones, but right now they do not.

*basically this app is on the same level as the apps that can read your fingerprint off the touchscreen

 

[scoson]

Cool, sounds like you're just the one to give the lowdown.

 

[sohguanh]

Actually chrlswltrs has a valid point. Android SDK only support hardware as documented in SensorManager | Android Developers

So using logical thinking, to detect radiation we can use those hardware supported by Android? Hmmm.... unless the Android smart-phone is specially built with additional hardware but that would mean no API is available to get reading off that additional hardware isn't it ?

 

[euph_22]

While this app does sound intriguing, I do not believe it is at all possible. There is no way a camera can detect radiation of any type. It requires completely different hardware and sensors.

I am saying this because I worked in the nuclear field for several years, and was personally responsible for conduction radiation surveys and controlling radioactive material. I have extensive knowledge of radiation and how it is detected, and currently cell phones do not have the required hardware. Someday they might have the hardware in specially designed phones, but right now they do not.

*basically this app is on the same level as the apps that can read your fingerprint off the touchscreen

Light is a form of radiation. It's just non-ionizing radiation.

It seems CMOS detectors are actually widely used in scintillation detectors already, it's just a matter of getting a useful recognition algorithm for CMOS Sensors designed for visible light. The idea being we could simply upload a software patch to turn CCTV cameras at airports, shipping ports, train stations, etc into (crude) radiation detectors. Enough to give a warning about potential nuclear materials. If a couple cameras detect a signal 1000x the normal background noise, DHS and the police show up with the real equipment and investigate. This app is largely just a sideshow/stepping stone to the real objective.

And it's not a Geiger counter (more correctly called a Geiger-Mueller detector). A GM counter consists of a sealed tube filled with inert gas. It works because ionizing radiation will, well ionized the gas when a ray of radiation hits a molecule of the gas, which in a cascade ionizes lots of other gas particles and creates a current pulse in the detector. This does a similar thing, but without the gas tube. This is technically closer to a scintillation counter. However, this whole paragraph is really just me being pedantic.

 

[Hadron]

Well if we are being pedantic I'll note that the CMOS detector used in a scintillation counter is actually measuring light produced by the scintillator, not acting directly as a nuclear radiation detector.

You are right that the camera sensor will respond to gammas, but the efficiency will be low. Whether the phone app could distinguish any flux you are ever likely to encounter from electronic noise in the sensor would be the trick. But as you say, the app's not the main game.

 

[euph_22]

Well if we are being pedantic I'll note that the CMOS detector used in a scintillation counter is actually measuring light produced by the scintillator, not acting directly as a nuclear radiation detector.

Quite right. I should probably be more careful writing technical posts at 11pm while working on a DSP final. I will redeem myself slightly by mentioning that photo diodes are used to detect radiation like this. http://www.carroll-ramsey.com/detect.htm

You are right that the camera sensor will respond to gammas, but the efficiency will be low. Whether the phone app could distinguish any flux you are ever likely to encounter from electronic noise in the sensor would be the trick. But as you say, the app's not the main game.

I'd say even money that even if they get to a live field test, they'd be so buried by false alarms that they just turn the system off after 2 weeks.

 

[Epicurean]

Well, this explains why I couldn't find my cigar cutter with the Metal Detector app when I dropped it in the grass in the middle of the night. I always assumed it was "operator error", but now I am less convinced. ;-)