Archived posting to the Leica Users Group, 2000/03/11
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Having asked the question, I'm honoured to belong to a group that can provide this sort of resouce at a moments notice, it's amazing to hear how these things are produced and work. thanks, Jem - -----Original Message----- From: Jim Brick [SMTP:jimbrick@photoaccess.com] Sent: 10 March 2000 23:31 To: leica-users@mejac.palo-alto.ca.us; leica-users@mejac.palo-alto.ca.us Subject: [Leica] Re: Re: Leica and the digital future Philips makes a 6 megapixel sensor that is about the size of a 35mm frame. We have had one here for two years. It is a beast to use. It consists of four sensor quadrants that have to be read-out in parallel. This is because reading out 6 million pixels serially would be very time consuming. You then have to re-assemble the raw image via software after it is read out, run it through a Photo Response Non-uniformity algorithm, through an interpolator and color space converter, then into a JPEG converter to produce a usable file. Because of their size, and low fabrication yield, they are very very expensive. I believe one of the new Canon or Nikon $15,000 to $25,000 cameras uses this chip. Jim At 09:59 AM 3/10/00 -0800, Brian Reid wrote: >> Jim, (or others) are we ever likely to see 24x36mm chips sitting >> in the back of our (by then) old 35mm cameras? > >I spent a few years working in chip fab, so let me take a stab at this. > >Basically the way you make a chip is as follows: > >1. Start with a round wafer of silicon that is as big as you can >muster. These days you can find 12-inch wafers; I've never personally >handled one bigger than 6 inches. > ><snip> > >It costs you the same to process a wafer whether all of the chips fail >or all of the chips work, so profitability in this business comes >entirely from "yield", from the number of chips on a wafer that >actually work. Bigger chips are less likely to work, so are less >profitable, so they are more expensive. > >Brian