Visual acuity tester with improved test character generation

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

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

351237, A61B 302

Patent

active

058808140

ABSTRACT:
A visual acuity tester based on a personal computer is provided that is capable of displaying visual acuity test characters at varying sizes on a monitor. The visual acuity tester antialiases the test characters to overcome the effects of staircase distortion. Preferably, the visual acuity tester performs unweighted area sampling antialiasing. The visual acuity tester also centers the test characters relative to the pixel array of the monitor to improve the appearance of the test characters. The test characters can be centered relative to either the center of a pixel or the corner of a pixel (a pixel coordinate). Test characters can also be centered relative to a pixel center in one dimension and a pixel coordinate in the other dimension.

REFERENCES:
patent: 4239351 (1980-12-01), Williams et al.
patent: 4907282 (1990-03-01), Daly et al.
patent: 5026151 (1991-06-01), Waltuck et al.
patent: 5121981 (1992-06-01), Waltuck et al.
patent: 5337154 (1994-08-01), Dorricott et al.
patent: 5589897 (1996-12-01), Sinclair et al.
"Basic Raster Graphics Algorithms," in Computer Graphics Principles and Practice, Foley, VanDam, Feiner, and Hughes (Nov., 1992).
Bach, "The Freiburg Visual Acuity Test-Automatic Measurement of Visual Acuity," in Optometry and Vision Science, Jan., 1996.
Hersch, "Digital Typography and Raster Imaging: The Desk Top of the 90's," in Eurographics Technical Report Series, Sep., 1991.

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

Visual acuity tester with improved test character generation does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Visual acuity tester with improved test character generation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Visual acuity tester with improved test character generation will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1326500

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