Canon has patented a multi-layered image sensor that consists of five layers instead of three, the amount currently available in Sigma’s Foveon X3 sensors.
The most popular multi-layered image sensor is the one found in Sigma cameras. There are multiple versions of the Foveon sensor and the most recent one has found its way in the Sigma Quattro cameras.
A Foveon sensor has three sheets of pixels, each being sensible to a color of the RGB spectrum. This means that Sigma DP Quattro cameras have a sheet of pixels for the red color, one for the green color, and another one for the blue color.
Canon has been rumored to be working on a multi-layered sensor for a very long time. In fact, the company has even patented a version of such sensor a few years ago. However, it has not made its way onto the market for the time being.
Nevertheless, it appears that Canon has not abandoned the plans to revolutionize the market as the Japanese manufacturer has just patented an image sensor with five layers of pixels.
Revolutionary Canon image sensor patented in Japan
A lot of people are claiming that there is nothing wrong with Bayer sensors and that Sigma’s Foveon is overrated. However, tests have shown that multi-layered sensors are providing exceptional image sharpness and are exhibiting great image quality.
Canon is aiming to take things to the next level. According to the latest patent, the manufacturer’s logic seems to go like this: why go for only three layers when you can put five layers in an image sensor?
Three layers are for the Blue, Green, and Red colors. This is the order described in the patent and shows how they are stacked on one another. Another layer is to filter ultraviolet light and will be placed on top of the Blue one, while the final layer sits below the Red sheet and it is there to filter infrared light.
The revolutionary Canon image sensor appears to be based on backside illumination (BSI) technology and will provide astonishing image quality.
Why would Canon add UV and IR layers in an image sensor?
The patent is describing a technique that would be useful in portrait photography. It appears that this sensor will allow a camera to correct how a person looks in a photo by erasing stains and wrinkles.
Since all the light will be filtered, there will be no more low-contrast worries and the images will turn out great.
For now there is too little information available on the web to draw a conclusion. It is unlikely that this is the Canon revolution everybody is expecting to be revealed with the 7D Mark II
Check out the full patent at Egami, where it is available in the Japanese language, although Google or Bing Translate will do a decent job at transcribing the details of the patent.