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. 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. Ishihara Test Chart Books for Color Deficiency 38 Plates Latest Edition Blue color with User Manual Includes four special plates for tests to determine the kind and degree of defect in color vision