> On Wed, Aug 4, 2010 at 12:42 PM, Olin Lathrop = wrote: >=20 > >> In a related area, early video camera elements were made from DRAMs > >> with out covers over the chips. > > > > I think that was a later development. =A0I'm reasonably sure using DRAM= s as > > image sensors was pioneered by Bill Yerazunis of the Mitsubishi Electro= nic > > Research Labs in Cambridge MA in the mid to late 1990s. =A0You may reme= mber > > him as "Crash" on the NERDS team of some Junkyard Wars episodes. I remember a colleague talking of doing this in the early 1980s, using a 16= k dynamic ram chip. They only came in ceramic packages at that stage so get= ting the lid off to see the chip was easy enough, and required triple suppl= ies. There were problems though, you couldn't just step through the address= to get the next pixel. The address lines were 'randomly' arranged in their= decoding to minimise inter cell cross talk inside the chip, so until you w= orked out the cell to address line mapping you could get a picture, but not= one that made sense to human eyeballs. I guess someone worked out a clever= scheme to do this using vertical, horizontal and diagonal lines until they= could get a perfect picture every time. Major problem was the chip was long and narrow, so the aspect ratio wasn't = optimal. He may have also played with 4k chips which came in a wider packag= e as they were not as fine geometry, so may have had a better aspect ratio. --=20 Scanned by iCritical. --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .