Hi Rick
> Don't be fooled by the odd chip size designation, which is a carryover from video terminology. A 1/1.7" chip is 7.2 X 5.7 mm,
Ah – I am going to have to disagree with you here. The Wikipedia entry you gave is VERY misleading and out of date. It should be replaced imho with a more up-to-date entry. I think the Ricoh sensor chip is literally 1" x 1.75" in size. This is not an uncommon size today.
You see, in the earlier days of digital photography there was a lot of confusion about focal length and image sensor size. So in an effort to phrase things in a language 'traditional' camera owners could understand, the manufacturers kept talking in terms of a 35 mm SLR equivalent. The Wiki entry dates from those days.
But that was years ago, and the industry does not do that much these days. It turned out to be even less comprehensible. The idea of complex calculations about chip size vs 35 mm film size have been forgotten. Where an SLR lens equivalent is quoted, it is done in a much looser fashion, just comparing the finished picture.
Anyhow, the idea of getting 10 MPixels on a 7.2 x 5.7 mm chip in the Ricoh camera is … not realistic. Certainly not if you want to be able to push the equivalent ISO rating (another vestigual left-over from film) up to 1,600! You need a big pixel area for that.
I might be wrong about the chip size, but I think some fundamental laws of physics as I understand them would need to be violated along the way. They would need to put 3,648 pixels across 7.2 mm, and that would make the pixels about 2 microns across. Well, the diffusion length of an electron in silicon is about 6-7 microns, so a single image point/electron would effectively be smeared across about 10-12 pixels. Makes no sense that way. If the chip is 1.7" wide, the pixels would be about 10 microns wide – and that is about right for the industry today, and for good dynamic range.
Background: 20+ years in image analysis and video camera systems, plus undergraduate degree in semiconductor physics, plus following the semiconductor chip industry for most of my working life.
:-)
Cheers
Roger