Lens systems for projection televisions

Television – Video display – Projection device

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C348S781000, C359S650000, C359S772000, C359S780000, C359S649000

Reexamination Certificate

active

07133084

ABSTRACT:
Projection lens systems for use with cathode ray tube (CRT) projection televisions are provided which have positive first lens units (U1) and negative second lens units (U2) where the negative second lens units are customized in terms of at least one optical property for at least two of the colors of light produced by the CRTs with which the units are used. The at least one optical property is not spectral transmission, although the second lens units can also be customized for spectral transmission. As illustrated in FIGS.1B–1F and FIGS.8B–8F, such customization of a non-transmissive property provides an effective and cost effective approach for improving the color performance of CRT projection lens systems. Constructions for the positive first lens unit which improve image contrast and reduce manufacturing costs are also provided.

REFERENCES:
patent: 4699476 (1987-10-01), Clarke
patent: 4776681 (1988-10-01), Moskovich
patent: 4884879 (1989-12-01), Fukuda et al.
patent: 4948237 (1990-08-01), Hirata et al.
patent: 4950062 (1990-08-01), Kimura et al.
patent: 5029993 (1991-07-01), Fukuda et al.
patent: 5045930 (1991-09-01), Hasegawa
patent: 5055922 (1991-10-01), Wessling
patent: 5200814 (1993-04-01), Hirata et al.
patent: 5293226 (1994-03-01), Yamamoto et al.
patent: 5537167 (1996-07-01), Toide et al.
patent: 5633757 (1997-05-01), Park
patent: 5659424 (1997-08-01), Osawa et al.
patent: 6297860 (2001-10-01), Moskovich
patent: 6301056 (2001-10-01), Kreitzer
patent: 6324014 (2001-11-01), Moskovich
patent: 06 082693 (1994-03-01), None
patent: 09138346 (1997-05-01), None
Dunham et al., “Minimax Approximation by a Semi-Circle”,SIAM J. Numer. Anal., 17:63-65, 1980.

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

Lens systems for projection televisions does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Lens systems for projection televisions, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Lens systems for projection televisions will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3648882

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