Path: utzoo!attcan!uunet!cs.utexas.edu!mailrus!bbn!eddie!mit-amt!mit-caf!fritz From: fritz@mit-caf.MIT.EDU (Frederick Herrmann) Newsgroups: sci.electronics Subject: Re: Batty monitors and cheap video Message-ID: <3254@mit-caf.MIT.EDU> Date: 30 Sep 89 21:15:33 GMT References: <1989Sep28.122217.26867@watcsc.waterloo.edu> <57732@psuecl.bitnet> Reply-To: fritz@mit-caf.UUCP (Frederick Herrmann) Distribution: sci.electronics Organization: Microsystems Technology Laboratories, MIT Lines: 26 In article <57732@psuecl.bitnet> peg@psuecl.bitnet writes: >> First of all, take a 4kX1 bit DRAM and somehow expose the silicon. \ > >Do you have a clean room handy? :-) As a matter of fact, there are a couple of dandy ones in my building. But the easy way is to buy parts in windowed packages. >> To use the thing as a camera, just charge up the thing to all 1's, \ >> wait for a >> bit, and then check which bits are discharged by the ambient light. > >Well, this actually works, in a manner of speaking. The devices are called >CCD's, charged coupled devices, and are used for picture tubes in most Let's be careful with terminology here. You don't need CCDs to build an IC imager, as the `RAMera' demonstrates. A CCD is a kind of `analog shift register' which moves packets of charge between the the channels of adjacent MOSFETs. In the IC `picture tubes' you mention, CCD are used to shift out the contents of the image sensor array in a serial format for video output. I think Ciarcia had a RAMera-like project in Byte a few years back. - Fritz fritz@caf.mit.edu