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Embedded Linux On a High Speed Camera
destructor writes: "Linuxdevices has an interesting article on a High Speed Gated Intensified Camera that
"combines a fast gated micro-channel plate (MCP) image intensifier, a CMOS image sensor, and an embedded computer based on an Axis Communications ETRAX RISC processor running Embedded Linux." The camera (Elphel Model 303) itself is network operable and can be used for capturing images of explosions, lightning bolts, etc. Link found via. megarad.com."
"Intensified" comes from image intensifiers -- vacuum tubes similar to those for the nigh-vision devices.
Actually, the blurb mentions it uses a microchannel plate. In a standard photo-multiplier tube, a photon hits the cathode plate of a "tube", kicking out an electron, which is then accelerated towards the anode. Here they can be used to generate an electrical signal, or more commonly knock out even more electrons to be accelerated towards and even more positively charged anode for a stronger signal, and so on. These "tubes" are carefully arranged in a (kind of) circular array to make sure as many of the accelerated electrons hit the next anode.
A microchannel plate works in essentially the same way, except that the initial photoelectrons are accelerated down narrow tubes instead of a series of anodes. As the electrons collide with the walls of the tubes, they knock more electrons free, these collide again, etc. Also, using narrow tubes like this preserves the spatial resolution of the original photoelectrons - light hitting a small region of the detector produces photoelectrons in only that area and the signal is amplified by only a few of these tubes, producing a final signal in that one spot at the other end of the MCP.