US Patent 9155461 Shape discrimination vision assessment and tracking system

A handheld vision tester and a method of self-testing vision of a user of the handheld vision tester are provided. The method ensures that a display of the handheld vision tester is within an acceptable distance to eyes of the user. Variations of the acceptable distance are compensated for. The method further displays different shapes, either dynamically or statically, on the display to the user. The method also allows for input to the handheld vision tester by the user in response to the different shapes displayed. Results of the self-test are determined from the inputs to the handheld tester by the user.