Apparatus and methods for extending depth of field in image projection systems

US6069738A · kind A · utility

Assignee

• The Regents of the University of Technology Office of Technology Transfer · US

Inventors

• Wade Thomas Cathey, Jr. · Boulder, US
• Edward R. Dowski, Jr. · Lafayette, US

Key dates

• Filing date: May 7, 1999
• Grant date: May 30, 2000
• Expiry date: May 7, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70433
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An optical system for providing an in-focus, extended depth of field image on a projection surface includes an encoded mask or light encoder for preceding the light to include object information (or, equivalently, information about the desired image), and an extended depth of field (EDF) mask, for extending the depth of field of the projection system. In addition to including object information, the encoded mask encodes the light from the light source to account for the variations introduced by the EDF mask in extending the depth of field, so that no post processing is required.