Canon 3 Layer Sensor (Foveon Type?) Patent

[Canon Rumors]

A Canon Foveon Type Sensor?

3 Layer Image Sensor A Canon patent was recently released showing a 3 layer sensor. Sigma has been the leader (I use the term lightly) in this type of sensor design when they purchased Foveon.

Patent Publication No. 2011-129785

• 2011.6.30 Release Date
• 2009.12.18 filing date

Canon patent

• Back-illuminated imaging device
• Plurality of light receiving portion is provided in the order BGR
• In one pixel, the charge collection in the center section, provided the charge read to the end
• Focusing capabilities of the microlenses, light in the center of the charge collection has increased, the charge read out at the end of the light is reduced
• Therefore, in reading the charge of B, it becomes difficult to receive light G, to prevent mixing
• Widest area of ​​B. By mixing pixels with narrow spacing of the pixels (light receiving portion for receiving the G colored in B) to prevent
• Read the charge and B matches the central microlens. And easy to read the charges received by B, to prevent mixing
• Improve performance by preventing the mixing color separation

Canon is a sensor manufacturer, this sort of research and development was almost a given. There’s lots of advancements to be made in sensor technology.

If anyone has better knowledge of this type of technology, please join the discussion on the forum thread.

thanks Evgnii

cr

[dr croubie]

The text is (as always) mostly unintelligible. and i wish the diagram was a bit larger.

ok, i've changed what i originally thought. It didn't look like a sensor on first inspection, but now i've convinced myself it is.

with the 'Set' FET off, nothing happens.
turn the Set FET on, and one of the TxR/G/B FETs on, and the voltage at the filled-in dot at the right will change proportionally to the voltage at the '101' layer.
Turn that FET off, turn on the next TxRGB FET, and read the voltage .

the line:
"Therefore, in reading the charge of B, it becomes difficult to receive light G, to prevent mixing"
mean that only one colour can be read at a time sequentially. Turning 2 or 3 FETs on at once, the voltage will be proportional to total charge on all 3 combined (added or averaged, not sure).
So you expose your sensor using the shutter, black it off, then read every pixel's colour sequentially before the charge dissipates (switching FETs on and off can be done in the order of nanoseconds).

turn the 'Res' FET on to reset the charges on everything.

[Peter Canon]

How long before someone posts they are not buying a new camera and waiting for one with the new Sensor?

[gkreis]

How long before someone posts they are not buying a new camera and waiting for one with the new Sensor?

I know I won't buy again until I see that sensor in a mirrorless Canon.....




  hmm..... 16 minutes?

[x-vision]

Combining BSI with a 3-layer design is a pretty innovative idea.

From what I understand, though, both of these individually are already very hard to implement in practice.
So, I'm assuming that combining them in a single design will be even harder.

But if Canon can pull this off, it will be a sensor nirvana .

[LFG530]

If canon goes trough with it, I'm really glad to see them do something innovative instead of their "status quo" on the sensor thing. I mean competition like fuji (super ccd (s5), exr)/sigma (foveon)/sony (great noise performance) are a bit more agressive on that aspect and it's about time the "leader" of the industry does something to crush the competition .

[pavel89l]

Could this be future HDR enabled sensor...?? Anyone?

[kalieaire]

This is interesting news.  It looks like Canon was making the exact same sensor that Foveon embarked on over 10 years ago.  However, they made some interesting discoveries into counteract some issues the Foveon sensor always had.

So the story is that Foveon, when they first made their 3 layer sensor, the reason that it took so long to come to market was the fact that the green layer had some terrible sensitivity issues, to the point where they had to artificially increase gain to get the signal through.  Red, even though being the furthest layer away, had no issues, and blue obviously had none as well because it was on top.  The key to everything was that green and blue were so close together in the spectrum that it was difficult for the green filtered sensor layer to distinguish the blue.

The patent sounds like a way to rectify this issue completely.  Sadly, if Canon is ultimately successful, I think we will see Foveon disappearing very quickly.  I'll be sad to see Foveon go, I was really rootin' for them.

[kawasakiguy37]

Smells of video to me. Like the old 3 CCD's but all in one

[kirillica]

Well, can someone translate into readable language what this patent is for and why it is (a way?) better than current stuff? 

[FranciscoDurand]

Well, can someone translate into readable language what this patent is for and why it is (a way?) better than current stuff? 

Well the foveon sensor has 3 independent layers (blue, red, green) while the CMOS sensors has the bayer grid, the difference between those sensors is that the foveon captures all blue, all green, all red, images while the CMOS mix 'em all. You can read more in wikipedia sites  about this superb sensor and about the Sigma SD1.

And I think this sensor would be in the new Canon 5D Mark III? 

http://en.wikipedia.org/wiki/Foveon_X3_sensor

[kirillica]

Well, can someone translate into readable language what this patent is for and why it is (a way?) better than current stuff? 

Well the foveon sensor has 3 independent layers (blue, red, green) while the CMOS sensors has the bayer grid, the difference between those sensors is that the foveon captures all blue, all green, all red, images while the CMOS mix 'em all. You can read more in wikipedia sites  about this superb sensor and about the Sigma SD1.

And I think this sensor would be in the new Canon 5D Mark III? 

http://en.wikipedia.org/wiki/Foveon_X3_sensor

Wiki says some interesting stuff:

The Foveon X3 sensor, as used in the Sigma SD10 camera, has been characterized by two independent reviewers as noisier than the sensors in some other DSLRs using the Bayer sensor at higher ISO film speed equivalents,[33] and specifically chroma noise has been noted.[34][35] Another has noted higher noise during long exposure times.[36] However, these reviewers offer no opinion as to whether this is an inherent property of the sensor or the camera's image processing algorithms.

So separate channels are good from this point of view:

Because demosaicing is not required for the Foveon X3 sensor to produce a full-color image, the color artifacts ("colored jaggies") associated with that process are not seen.

But noise... Maybe Canon will use it in new product line (medium format)? Large sensor, no need in high iso during studio shots and etc.

[afrank99]

Could this be future HDR enabled sensor...?? Anyone?

We all have HDR enabled sensors since every DSLR records 10, 12, 14 or more bits of luminance.

Or what is your definition of "HDR"?

[FranciscoDurand]

But noise... Maybe Canon will use it in new product line (medium format)? Large sensor, no need in high iso during studio shots and etc.

Hmm, wikipedia says that the sensor is noisy but no, its not the new Foveon sensor x3 that they use in the sigma sd1 (46 mp) its not noisy at all.

EDIT: Btw i found this image that compares Sigma Sd1 (foveon sensor) with 5dmk2, dp2 and nex 5


Sigma sD1 has richer colors because of the independent layers.

[kirillica]

I wonder why they (Sgima) call it (SD1) 46Mp camera, because actually it produces 46/3~=15Mp pictures. And "moderate" noise (mentioned in WiKi for Favion's new generation) + max ISO to 6400 mean that it's still significantly noiser Bayer's CMOS sensor (in 5dm2 ISO is up to 25600). So I still think it could be a patent for a medium-format product line