New Kodak technology for CMOS sensors

[rosuna]

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This is an interesting interview:

 

Kodak: A Thousand Nerds - Innovative Design Boosts CMOS Image Quality

 

I expect to see this idea applied to future CMOS sensors for reflex cameras, including the future Leica.

[okram]

What led you to first think about inventing a new sensor design?

We were working with a very demanding customer. They wanted the cost and speed advantages of CMOS with the photographic performance of CCD sensors.

[rosuna]

There are several interesting quotes.

 

So this new design would bring a significant boost to the quality for large sensors?

 

Yes, but there are many advantages other than reduced crosstalk. As we mentioned earlier, the dark current is lower. This is very important for digital still cameras and applications. The well structure itself reduces dark current.

 

This new design applies to all pixel sizes, but it is especially advantageous for the really small pixels.

The problem of crosstalk does get worse as pixel sizes shrink, yes. But even for the full-size 35 mm image sensors, it still helps.

 

This customer was asking you to find a way to use less expensive technology but still provide image quality that was close to CCD quality.

Yes, they knew Kodak's reputation as a very high-end sensor designer and manufacturer. Their quality and device specifications were similar to those for a CCD. It was a high-end photographic application.

[zapp]

This is an interesting interview:

 

Kodak: A Thousand Nerds - Innovative Design Boosts CMOS Image Quality

 

I expect to see this idea applied to future CMOS sensors for reflex cameras, including the future Leica.

 

5 years behind of Canon, aren't they?

[rosuna]

I don't know what is the technology developed by Canon for their CMOS sensors. Their performance is impressive. Kodak was a CCD imaging company, and only recently they took the CMOS route (at least for compact cameras):

 

A Thousand Nerds: A Kodak blog about innovation

 

I would like to know more about the Nikon D3 sensor design, because it seems to be a new generation design on par, if not better, than Canon's 5D sensor.

[Jamie Roberts]

5 years behind of Canon, aren't they?

 

Yes, except for image quality! Where is Canon's MF sensor again?

[colorflow]

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5 years behind of Canon, aren't they?

 

Not exactly, see A Thousand Nerds: A Kodak blog about innovation for the type of CMOS sensors Canon uses.

[rosuna]

Because a CMOS sensor can be "smarter" than a CCD sensor, the use of CMOS image sensors can result in a simpler camera design (because fewer parts are required). CMOS designs also tend to run at lower voltages, which helps to reduce power consumption (leading to longer battery life).

 

... although some people say the contrary.

 

The problem, of course, is that the image quality available from CMOS image sensors historically has not been as good as what you can get from CCDs.

 

But image quality has improved in CMOS designs, with superb noise handling and treatment. The Canon 5D was really good, and it is an "old" design.

 

So has CMOS finally caught up to CCD? Is the image quality available from both technologies now basically the same?

I wouldn't say they're the same, but CMOS is certainly closing the gap quickly. There's a lot of work that has been going on the past few years to improve the quality of CMOS pixels.

 

I expect to see new Kodak designs for large CMOS sensors, for medium format and 35mm format.

[rosuna]

New techologies are coming:

 

100x Sensitivity Image Sensor Based on Solar-cell Structure -- Tech-On!

 

R.

[colorflow]

[quote=rosuna;544384

But image quality has improved in CMOS designs, with superb noise handling and treatment. The Canon 5D was really good, and it is an "old" design.

 

I know very little about sensor technology but my guess, which may be entirely wrong, is that the "old" design maximized the real estate on the chip for use by the pixels to collect light and left much of the processing logic off the sensor chip. This way the signal to noise ratio is maximized but still requirined off the chip signal processing with additional electronics. This does not take full advantage of the efficiency and economics provided by CMOS technology integration.

 

I think the "new' design is to take full advantage of CMOS integration by giving up some of the light collecting real estate on the chip to processing logic. This then requires new approaches to maintain high signal to noise with the smaller pixels.

 

Does that sound reasonable???

 

Alan

[rosuna]

Canon claims the 1Ds Mark III has the same light sensitive area (fill factor) than the 1Ds Mark II. These CMOS sensors have a lot of circuitry into each pixel. I think they have reduced the total size of these transistors and have improved the microlens design. The "new" way seems to be related with the nMOS vs pMOS paradigm (see the first link). The Nikon D3, on the other hand, has very big pixels (8.5 microns), and this helps in obtaining that incredible performance.

 

I know the theoretical advantages of CCDs, but in practical terms CMOS sensors are providing features and performance difficult to match. This CMOS "superiority" (so to speak) explains to some extent the strong competitive pressure of the 35mm format DSLR cameras against the medium format market.

[colorflow]

Seems they are saying that p-type substrate and "hole" paradigm allow the use of conventional CMOS devices while p-MOS pixels with n-wells have lower noise and cross-talk.

 

Isn't Canon n-MOS which would be limiting for device integration?

 

Alan

[rosuna]

This is the point in which I loss track. I don't know what technology is using Canon... or Nikon, this is, last generation sensors...