CanonNews / Monday, August 12, 2019

Canon Patent Application: Expanded Sensor Dynamic Range using DPAF sensors

I know many have speculated that this could be done with DPAF sensors. The basic idea is that during read mode, one half of the pixel is amplified at one level, and the other half is amplified at another level. reading the two simultaneously and processing can increase the dynamic range of the sensor. Basically dual ISO.

Canon seems to agree with this, and has filed a patent application on very subject - is this something we can expect to see in our cameras? the basics are already there - since DPAF sensors already read each half of the pixel to produce autofocus information. All that is needed is to selectively choose to amplify each half of the pixel differently.

Canon states (and you have to get into the weeds of this patent application really);

Therefore, outputs with two different gains can be taken out simultaneously with respect to the signal output of the same pixel 200. By processing these two gain signal outputs in combination, the dynamic range of the photoelectric conversion device 100 can be improved.

This patent is also a good primer if you were ever curious on what happens under the hood of a DPAF sensor.

While some parts of this patent application seem to apply for vehicle sensors, Canon does state that it can apply to any sensor in a camera or otherwise;

The photoelectric conversion devices described in the first to fourth embodiments can be applied to various imaging systems. Applicable imaging systems are not particularly limited. For example, digital still cameras, digital camcorders, surveillance cameras, copying machines, fax machines, mobile phones,
Various devices such as in-vehicle cameras, observation satellites, and medical cameras can be listed.

Canon Japan Patent Application 2019-129491