Look, ma... NO microlenses!

[jlw]

Did anybody else notice this news release on Digital Photo Review the other day?

Here's a link to it.

For the link-deprived, it's a news release from Cypress Semiconductor about their new imager chip. It uses CMOS technology (which Canon has proved can work fine); is APS-size (meaning the same size used in the Epson R-D 1 and all Nikon DSLRs -- big enough for a lot of people, including me); and the biggie... does NOT require a microlens array, thanks to their "proprietary, high-fill-factor pixel architecture."

Of course, to coin a phrase, there's many a slip 'twixt the chip and the ship (i.e., between announcing a new imager and producing a good shipping product.) But if I understand this issue correctly, it's the need for microlenses that's one of the main challenges to designing a digital RF camera that uses an existing lens line -- so it's especially good news for us RF users when any sensor manufacturer tries to think outside the microlens box.

This news release has some interesting implications for the imaginative gossip-monger. Granted, 9 megapixels doesn't sound like a lot in today's marketplace... although my 6-megapixel Epson R-D 1 has made me a lot of pictures with which I'm very happy, so presumably a 9-megapixel imager would make me 50% happier.

But going beyond that... the news release notes that Cypress acquired Belgian chipmaker FillFactory in 2004, making them (plausibly) a European sensor maker.

Could a low-cost chip with no microlenses be the secret ingredient behind a viable digital RF, frequently rumored to be coming soon at a surprisingly semi-reasonable price from a certain very-well-respected German company, using sensors from an unspecified European maker?

 

[jlw]

Hmmm... I'll have to check the specs again, but my understanding was that just about all small-format digital sensors DO use microlenses.

The problem they solve isn't so much with back focus as with the very small size of the photosites (the actual area within each pixel that's sensitive to light, for you digiphobes.) In a typical small-format sensor, the photosites are so small that most of the light hitting the imager misses them entirely -- drastically lowering their efficiency. The microlens array works like the condenser in an enlarger, concentrating light on the photosite so less of it is lost.

The large-format sensors used in studio camera digital backs have larger photosites and don't need microlenses -- that's how they get away with providing swings and tilts and such, with no lens-alignment problems to worry about. But these big-site sensors are hugely expensive to make, which accounts for the mind-bendingly high price tags of studio-camera digital backs.

Of course, Brian's in the imaging biz and I'm not, so if he's sure that most small-format imagers don't use microlenses, I'll have to defer. But I think their use is widespread, and that's why Cypress' introduction of a small-format, non-microlens sensor qualified as newsworthy and unusual.