Steven D Coffman

US Patent:

49988204, Mar 12, 1991

Filed:

Dec 12, 1988

Appl. No.:

7/282596

Inventors:

Cosmo Salibello - Portland OR
Jonathan G. Torrey - Portland OR
Steven G. Coffman - Portland OR
Gerald M. Murch - Portland OR

Assignee:

Applied Vision Concepts, Inc. - Portland OR

International Classification:

A61B 302

US Classification:

351243

Abstract:

An optical instrument for use in conducting optometric examinations which generates an alphanumeric type display simulating the optical features of displays provided by video display terminals. The instrument comprises a light source and a multi-layered screen through which light from the source may be transmitted. The screen employs light from the source in forming characters which are comprised of pixel-like light elements similar to those making up VDT generated characters. Further, the screen is operative for degrading the image quality of the characters by transforming the light elements into Gaussian type spatial profiles typical of the pixels generated by VDTs.

US Patent:

51913674, Mar 2, 1993

Filed:

Mar 7, 1991

Appl. No.:

7/665903

Inventors:

Cosmo Salibello - Portland OR
Jonathan G. Torrey - Portland OR
Steven G. Coffman - Bothell WA
Gerald M. Murch - Cupertino CA

Assignee:

Applied Vision Concepts, Inc. - Portland OR

International Classification:

A61B 302

US Classification:

351243

Abstract:

An optical instrument for use in conducting optometric examinations which generates an alphanumeric type display simulating the optical features of displays provided by video display terminals. The instrument comprises a light source and a multi-layered screen through which light from the source may be transmitted. The screen employs light from the source in forming characters which are comprised of pixel-like light elements similar to those making up VDT generated characters. Further, the screen is operative for degrading the image quality of the characters by transforming the light elements into Gaussian type spatial profiles typical of the pixels generated by VDTs.