Originally posted by slipchuck I wonder if anyone will try putting 2 or 4 small sensors together to act as one big one like they are are doing with processors (dual core, quad core, etc)
I would imagine it would be less expensive to make 2 or 4 separate sensors then one huge one.
for example 4 small sensors, each with 3 mg pixels per sensor, all acting as 12 mp.... could even make them (together) the same size as a full frame sensor the size of the canon ones
just an idea..
cheers
randy
The active area of the sensor is not the whole surface...some surrounding circuitry is required for image processing and readout - so there would be a gap.
However, FF sensors ARE made from 2 smaller sensors, in a way. The largest mask is current use for production chips (of any type) are around APSC size - hence they can be made using a one-pass process in a standard foundry (which makes memory, processors etc) and are relatively cheap.
To make a FF sensor you need to use a 2-pass process - one for the left half and one for the right half. The alignment has to be perfect for the resulting chip to be defect free hence such processes are expensive and the yield is much lower. As a result, the chips themselves are about 10X the cost. Interestingly, the MF chip is about 2X FF size, so this is probably a 4 pass process.
The fact that existing foundries can be used makes production of CCDs and CMOS sensors cost effective. To build dedicated foundries would be very expensive given the number of devices produced (you need millions to break even).