Illumination optical system
US5786939A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 30, 1997 |
| Grant date | Jul 28, 1998 |
| Priority date | — |
| Expiry date | Jan 30, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B21/006
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In an integrator illumination type illumination optical system, the opening shapes of respective lenses at first and second lens array plates (surfaces) are made substantially conformable to the shape of an area to be illuminated and predetermined conditional expressions are satisfied, thereby securely improving the light utilization efficiency and reducing the fluctuation in illumination. The illumination optical system comprises a light source portion constituted by an emitter (1) and an ellipsoidal mirror reflector (3) which reflects, in the direction of an optical axis X, luminous fluxes (2) emitted from the emitter (1); a first lens array plate (4) which acts on the luminous fluxes (2) from the light source portion; a second lens array plate (5) which superposes the respective luminous fluxes from the first lens array plate (4) onto a liquid crystal panel (7) which is an object to be illuminated; and a convex lens (6). The opening shapes of the respective lenses in the first lens array plates (4) and second lens array plate (5) are made substantially conformable to the shape of the front surface of the liquid crystal panel (7), while four conditional expressions defining the r…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.