Eye refractometer

Optics: eye examining – vision testing and correcting – Eye examining or testing instrument – Objective type

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

351211, A61B 310

Patent

active

047610700

ABSTRACT:
An eye refractometer is disclosed. It comprises a projection optical system including a light source portion and an objective lens disposed opposite to an eye under test, and a ring-shaped diaphragm or perforated mirror for forming a ring-shaped image pattern of the pupil of the eye and on the retina, a bundle of rays from the light source are projected to the eye under test through the objective lens and the diaphragm to form a ring-shaped pattern image at the retina of the eye under test through the peripheral area of a pupil surface of the eye under test; a light receiving optical system for receiving light reflected from the retina in a ring-shaped pattern image on a photo-electric detector through the central portion of the pupil; and a microprocessor for measuring the size and the configuration of the ring-shpaed pattern image from signals emitted from the photo-electric detector, and determining the refractivity of the eye under test therefrom.

REFERENCES:
patent: 4293198 (1981-10-01), Kohayakawa et al.
patent: 4376573 (1983-03-01), Matsumura et al.
patent: 4432617 (1984-02-01), Itoh et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Eye refractometer does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Eye refractometer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Eye refractometer will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-709477

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.