 A perceived range of colors resulted from the blending of the separate red and green alternating images by the viewer's persistence of vision.William Friese-Greene invented another additive color system called Biocolour, which was developed by his son Claude Friese-Greene after William's death in 1921.William sued George Albert Smith, alleging that the Kinemacolor process infringed on the patents for his Bioschemes, Ltd.; as a result, Smith's patent was revoked in 1914.