A week after announcing an image sensor with a whopping 120 megapixels, Canon revealed Monday it's created another boundary-pushing prototype: a chip with a light-gathering area measuring a vast 202x205mm.
The huge sensor is 40 times larger than even Canon's largest commercial image sensors, the full-frame chips measuring 36x24mm used in high-end SLRs. Indeed, it's a lot larger: big enough to swallow most of the surface area of the 300mm-diameter silicon crystal out of which it's made using a CMOS (complementary metal oxide semiconductor) process.
Notably, it employs new circuitry Canon had to develop to pump data off the processor fast enough to keep up with video.
One reason to build larger sensors is to increase their light-gathering area, and Canon delivers the goods here. It can record 60-frame-per-second video with light levels of 0.3 lux--about what a full moon overhead produces by some measurements.
"Potential applications for the new high-sensitivity CMOS sensor include the video recording of stars in the night sky and nocturnal animal behavior," Canon said.
Using such a sensor in the real world, though, would likely be a rarity. Although film negatives can be that large and indeed larger, it's rare that cameras and lenses are designed to shine an image that large.
Building an image sensor with a 300mm silicon wafer is also notable. Canon's full-frame processors today are built with smaller 200mm wafers. Using larger wafers cuts production costs but requires expensive retooling.
Many in the microprocessor industry moved to 300mm wafers years ago. Canon has managed to keep its sensors competitive overall, but faces pressure from Sony and others. Once an unusual case of an image sensor maker using CMOS technology, Canon has seen its competitors follow suit with CMOS image sensor designs for higher-end cameras.
Canon pledged to keep advancing image-sensor technology. "Through the further development of distinctive CMOS image sensors, Canon will break new ground in the world of new image expression, in the area of still images as well as video," the company said.