Patent ID: 9271641
Filing Date: 2016-03-01
CPC Classification: A61B

Claim Text:
1. An apparatus for determining a sensitivity of cone photoreceptors in a subject, the apparatus comprising: a. a first light source generating a first optical beam to create an adapting field to saturate the subject's rod photoreceptors; b. a first modifying element to modify a first characteristic of the adapting field and a second modifying element to modify a second characteristic of the adapting field; c. a second light source generating a second optical beam to create a target image to stimulate the subject's cone photoreceptors; d. a third modifying element to modify a characteristic of the target image; e. a beam splitter to join the adapting field and the target image created by the first and second optical beams, respectively, and f. a lens to image the adapting field and the target image at a location on a pupil of the subject, wherein either the target image is initially visible to the subject and the sensitivity of the cone photoreceptors is determined by modifying a first or second characteristic of the adapting field until the target image is no longer visible or the target image is not initially visible to the subject and the sensitivity of the cone photoreceptors is determined by modifying a first or second characteristic of the adapting field until the target image is visible.