Re: fun things to try / laser pen questions

[P3D Gabriel Jacob <jacob@xxxxxxxxxxxxxx>]

John W Roberts writes

>anyone know the spectral sensitivity of typical consumer CCD video cameras?)

The CCD sensor in consumer video cameras are sensitive past the sensitivity
range of the human eye. For most people, the threshold of visible light is
in the region of 720nm. CCD in video cams peak at around 960nm but
manufacters usually put in a infrared filter to block it. My guess it won't
allow radiant energy past the 700nm wavelength, which is where infrared
region begins. If you want to try infrared 2d or 3d with a video cam this
filter would have to be taken out. Another option is to buy an inexpensive
CCD that doesn't incorporate the infrared filter. Two inexpensive videocams
that come to mind would be the B&W quickcam and the older FisherPrice 
PixelVision. Maybe even the new Tyco videocam might not have the filter.
In any case these cameras are quite sensitive to infrared and will even pick
up the signal from a tv remote control (signal from a tv remote control
emits infrared). They can be considered as simple infrared cameras!

Gabriel 



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