Leibson's Law

The megapixel wars continue as Kodak has just announced the KAF-50100 Image Sensor, a 50Mpixel (8176x6132 pixels) CCD sensor for large-format digital cameras. The sensor array measures 48x36mm (that's 1728 mm²). To keep on-chip speeds down, Kodak doubled the number of read channels on the sensor from the previous generation’s two to four. The net effect of this move is to double the number of output amplifiers and to halve the amplifiers’ bandwidth. The new sensor has four amplifiers running at 18 MHz as opposed to the previous generation’s two amplifiers running at 24 MHz. There’s less noise with this approach.

Another clever design trick is to add what Kodak is calling “pulse flushing,” which uses the anti-blooming drain in each receptor cell to drain the charge from all cells simultaneously just prior to exposure. In previous generations, the cells were drained by reading them out sequentially. Pulse flushing reduces the reset time on the sensor array from milliseconds to microseconds for faster “click to capture.”

In addition, Kodak has shifted the red microfilters 15nm towards blue to improve color accuracy. This change allows the sensor to get a better read on colors falling between the red and blue filters including yellow and orange. (Kodak’s familiar old yellow film boxes will be rendered more accurately, assuming you still have some around.)

Specs are here.