Accepted by leading authorities as a simple and accurate method for discovering congenital color blindness and red-green blindness, each in two forms, complete and incomplete. Includes four special plates for tests to determine the kind and degree of defect in color vision. Makes use of the peculiarity that in red-green blindness, blue and yellow appear remarkably bright compared with red and green. Color plates encased in specially designed album-type books for ease of handling. Detailed instructions included. The color plates are available in an album-type book for ease of handling. The books are printed in Japan and are protected by international copyright. Graham-Field has been the exclusive North American wholesale distributor of Ishihara Tests for over 30 years.