Title:
OPHTHALMOLGIC DECICE
Document Type and Number:
Japanese Patent JPS53126791
Kind Code:
A
Abstract:
An ophthalmoscopic instrument having an infrared image converter tube for observation and/or examination of an ocular fundus prior to recording an image thereof provided with a range finding device which assists in establishing a suitable working distance between an eye and an objective lens in the instrument optically aligned to each other. A light beam is projected onto the iris of an eye to be examined or the cornea thereof near or at the center and is transmitted by scattering reflection or regular reflection respectively from the iris or cornea to a photo-detecting system which produces an electrical output signal capable of reaching a peak value only when the transmitted light enters a slit ahead of a light sensitive surface or strikes that one of light sensitive segments which is adapted to be the most light responsive, as the device is moved in unison with the instrument body.
Inventors:
KOBAYAKAWA YOSHI
Application Number:
JP4172177A
Publication Date:
November 06, 1978
Filing Date:
April 12, 1977
Export Citation:
Assignee:
CANON KK
International Classes:
A61B3/10; A61B3/14; (IPC1-7): A61B3/12