Optical: systems and elements – Polarization without modulation – By relatively adjustable superimposed or in series polarizers
Patent
1992-08-26
1994-04-12
Lerner, Martin
Optical: systems and elements
Polarization without modulation
By relatively adjustable superimposed or in series polarizers
359497, 359499, G02B 532, G02B 2728, G02F 11335
Patent
active
053030834
ABSTRACT:
Liquid crystal light valve projection systems can use substantially all of the reading light from a high intensity reading light source by converting all single polarization state. Light reflected from a polarization beam splitter (44) that cannot be used because it is of wrong polarization state is recovered with improved efficiency, color balance and collimation by means of a polarization recovery prism (50) employing a reflective surface (56) interposed between two quarter-wave retarders (58,60). The light of wrong polarization from the polarizing beam splitter (44) is passed through a first quarter-wave retarder (58), which circularly polarizes the beam. The beam is then reflected from a mirrored surface (56) to reverse the direction of the circular polarization. The reflected beam of reversed circular polarization is then converted to a beam of light of the desired polarization by passage through a second quarter-wave retarder (60) and is transmitted in a path parallel to the path of the original beam together with light transmitted directly from the polarization beam splitter (44).
REFERENCES:
patent: 2449287 (1948-09-01), Flood
patent: 2748659 (1956-06-01), Geffcken et al.
patent: 4125843 (1978-11-01), Whitby
patent: 4844593 (1989-07-01), Parker et al.
patent: 5073830 (1991-12-01), Loucks
patent: 5077483 (1991-12-01), Cloonan et al.
patent: 5078482 (1992-01-01), Feldman et al.
patent: 5124841 (1992-06-01), Oishi
patent: 5164854 (1992-11-01), Takanashi et al.
patent: 5223956 (1993-06-01), Kramer et al.
patent: 5223975 (1993-06-01), Naganuma et al.
Blanchard Randall D.
Cross, Jr. Eugene W.
Shirley Ronald D.
Denson-Low Wanda K.
Grunebach Georgann S.
Gudmestad Terje
Hughes Aircraft Company
Lerner Martin
LandOfFree
Polarized light recovery does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Polarized light recovery, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Polarized light recovery will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2103555