IP Library Granted Patent US 8,038,298
Granted Patent B2
US 8,038,298 · App. 11/488,132 · Granted Oct 18, 2011

Projector device

Assignee: SANYO Electric Co., Ltd.
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Quick Facts
Patent No.
US 8,038,298
App. No.
11/488,132
Granted
Oct 18, 2011
Kind
B2
Abstract

A liquid crystal projector device of the present invention includes an optical system for receiving light from a lamp unit. The optical system is provided with a polarization beam splitter for extracting only an S wave out of P and S waves of the light emitted from the lamp unit, and also provided with a latter stage slit plate in contact with a light incidence surface of the polarization beam splitter. The latter stage slit plate is provided with a plurality of slits for allowing light incidence on the polarization beam splitter. A former stage slit plate is arranged in a position spaced apart from the latter stage slit plate along the optical axis toward the lamp unit. The former stage slit plate is provided with a plurality of slits overlapping in the optical axis direction with the respective slits of the latter stage slit plate.

Claims (10)

1. A projector device comprising:

a casing having disposed therein a light source; and

an optical system for receiving light from the light source to generate image light, the optical system having disposed on an optical axis thereof:

a polarization beam splitter for extracting only a first component wave out of first and second component waves of light vibrating in orthogonal directions, the polarization beam splitter comprising:

a polarizing plate, and

a half-wavelength plate joined to a light emergence surface thereof, the polarizing plate comprising:

a plurality of first interfaces for passing the second component wave therethrough and reflecting the first component wave, and

a plurality of second interfaces for reflecting the first component wave reflected by the first interfaces toward a light emergence direction, which are formed alternately in a direction intersecting the optical axis, the polarizing plate having a latter stage slit plate arranged in contact with or close to a light incidence surface thereof, the latter stage slit plate being provided with a plurality of slits at a plurality of locations corresponding to the first interfaces of the polarizing plate, the optical system being provided with a former stage slit plate in a position spaced apart along the optical axis from the latter stage slit plate toward the light source, the former stage slit plate being provided with a plurality of slits at a plurality of locations identically overlapping in width in the optical axis direction with the respective slits of the latter stage slit plate,

wherein the former stage slit plate and the latter stage slit plate are fixedly arranged in a setting groove formed on an optical system holding case and comprise a metal material having a coefficient of thermal conductivity higher than that of a material constituting the polarization beam splitter.

2. The projector device according to claim 1 , wherein an integrator lens is arranged between the former stage slit plate and the latter stage slit plate, the integrator lens comprising a material with a coefficient of thermal conductivity lower than that of a material constituting both slit plates.

Assignments (5)
CHANGE OF ADDRESS Recorded Feb 24, 2026
From: SANYO ELECTRIC CO., LTD.
To: SANYO ELECTRIC CO., LTD.
Reel/Frame 074982/0479 →
CHANGE OF ADDRESS Recorded Feb 24, 2026
From: SANYO ELECTRIC CO., LTD.
To: SANYO ELECTRIC CO., LTD.
Reel/Frame 074983/0494 →
NUNC PRO TUNC ASSIGNMENT Recorded Feb 24, 2026
From: SANYO ELECTRIC CO., LTD.
To: PANASONIC PROJECTOR & DISPLAY CORPORATION
Reel/Frame 074983/0875 →
TO CORRECT THE ASSIGNEE'S ADDRESS PREVIOUSLY RECORDED ON REEL 018112; FRAME 0818 Recorded Nov 17, 2006
From: NAKAGAWA, NORIO; SARUWATARI, TOSHIHIRO
To: SANYO ELECTRIC CO. LTD.
Reel/Frame 018611/0934 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 18, 2006
From: NAKAGAWA, NORIO; SARUWATARI, TOSHIHIRO
To: SANYO ELECTRIC CO., LTD.
Reel/Frame 018112/0818 →
Priority Claims (1)
JP 2005-209287 · Jul 19, 2005 · national
Continuity (1)
Related Publication 20070019164A1 · Jan 25, 2007