Projection lens and system
AssigneeDuke University
InventorsBiljana Tadic-Galeb, Robert E. Fischer
Life of this patent
Estimating the term…
Abstract
Projection lenses and projection lens systems are telecentric between an illumination subsystem and a set of imagers. The lenses and systems can exhibit color fringing correction, uniform imager illumination, athermalization, and component articulation for improved imaging. The lenses and systems may be employed in display apparatuses, such as folded display apparatuses that have decreased footprint size, but long effective projection lengths.
Claims43
A projection lens apparatus, comprising:
- a front lens unit;
- a back lens unit optically coupled to the front lens unit;
- a linear reflecting polarizer optically coupled to the back lens unit and the front lens unit that directs a portion of illumination light received from a light source to the back lens unit;
- and
- a first imager optically coupled to the linear reflecting polarizer and adapted to impart an image on the illumination light to create image light, wherein the reflecting linear reflecting polarizer directs the image light to the front lens unit and wherein the back lens unit and the reflecting linear polarizer are adapted to provide substantially telecentric light to the first imager.
The projection lens apparatus of claim, 10, wherein the chromatic separating element is adapted to recombine separated colored light received from the first and second imagers.
A projection lens system, comprising:
- a projection lens comprising:
- a front lens unit;
- a back lens unit optically coupled to the front lens unit;
- and
- a linear reflecting polarizer optically coupled to the back lens unit and the front lens unit;
- an imager optically coupled to the linear reflecting polarizer and disposed such that the back lens unit is between the reflecting linear polarizer and the imager, wherein the back lens unit and the reflecting linear polarizer are adapted to provide substantially telecentric light to the imager;
- folded optics adapted to receive image light from the imager through the projection lens;
- and
- a display screen adapted to received the image light from the folded optics for displaying an image.
A projection lens system, comprising:
- a projection lens comprising:
- a front lens unit;
- a back lens unit optically coupled to the front lens unit;
- and
- a linear reflecting polarizer optically coupled to the back lens unit and the front lens unit;
- an imager optically coupled to the linear reflecting polarizer and disposed such that the back lens unit is between the reflecting linear polarizer and the imager, wherein the linear reflecting polarizer is a multilayer optical film.
Dependencies are inferred from the claim text.