CanonWatch quotes Japanese-language Egami site that Canon has applied for RGB-W CFA pattern patent. The US version of this patent is available here and appears to describe an image processing pipeline for RGBW12 pattern proposed in the company's 2011 patent application:
Incidentally, SonyAlphaRumors publishes that the next generation Sony full-frame ILC might feature RGBW CFA under "impossible rumors" title:
"The Sony A7S III that will be announced next spring will be the first interchangeable lens camera featuring a RGBW sensor. This will result in an sensitivity increase of 84%. Additional improvements and the cooper wired backlight sensor will result in a total of over 1 fstop of noise improvement."
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| ◯, Δ, and x are assigned in descending quality order. |
Incidentally, SonyAlphaRumors publishes that the next generation Sony full-frame ILC might feature RGBW CFA under "impossible rumors" title:
"The Sony A7S III that will be announced next spring will be the first interchangeable lens camera featuring a RGBW sensor. This will result in an sensitivity increase of 84%. Additional improvements and the cooper wired backlight sensor will result in a total of over 1 fstop of noise improvement."
