Inability to distinguish one or more colours. The human retina contains three types of cone cells that absorb light in different parts of the spectrum. Absence of these types causes colour blindness to red, green, and blue. Colour blindness is a sex-linked recessive trait (see recessiveness) 20 times more common in men than in women.
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Wipo Publishes Patent of Yirong Huang for "Colour-Blindness Device and Colour-Blindness Testing Method" (Chinese Inventor)
Feb 20, 2013; GENEVA, Feb. 20 -- Publication No. WO/2013/020462 was published on Feb. 14.Title of the invention: "COLOUR-BLINDNESS DEVICE AND...