CMOS sensor inventor Eric Fossum discusses digital image sensors: Digital Photography Review.
Check out the video of the Lecture. Dr. Fossum attempts to address the societal and privacy implications of his invention the CMOS sensor. You don’t find too many scientists willing to engage in this type of presentation. And he brings the thorny issues early in the presentation so that he doesn’t run out of time to cover them by sticking them at the end.
Also interesting in this video is Dr. Fossum’s story about how he was assigned the task of improving the reliability of CCDs (charged coupled devices) that were being sent into space. Defects in the sensor could occur when a highly energetic particle entered the sensor and created a defect in the sensor itself (ruing the ability to read out data accurately from the chip). The CCD works by collecting a sample than moving it one step at a time out to the edge of the chip, where it then gets amplified and read, and recorded. So if a defect occurs, the buckets moving a particular row or column of pixels will hit the defect and alter the reading or stop it from reading altogether.
Dr. Fossum was able to get around this by building an amplifier into each pixel. This was achieved, hanks to the scaling down of micro-electronics available in silicon semi-conductors and Moore’s Law. A double-benefit of using CMOS semiconductors for the sensor is you can add all kinds of OTHER electronic circuits on the same chip as the sensor, so things get really interesting because you can integrate them on the silicon (bring up performance, bringing down costs). As Dr. Fossum says, “basically we can integrate so many things, we can create a full camera on a chip. All you do is add power, and out comes an image,…”
Also liked this quote, “The force of marketing is greater than the force of engineering…”
Lastly, he covers his research of quanta-image sensor (QIS) which sounds pretty interesting too.
