IP Library Granted Patent US 8,348,431
Granted Patent B2
US 8,348,431 · App. 13/480,532 · Granted Jan 8, 2013

Illumination apparatus and projection display apparatus

Assignee: Sanyo Electric Co., Ltd.
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Quick Facts
Patent No.
US 8,348,431
App. No.
13/480,532
Granted
Jan 8, 2013
Kind
B2
Abstract

An illumination apparatus includes multiple liquid crystal panels, a polarization-state adjusting element, and a cross dichroic prism. A green component light includes a central-wavelength component light, a short-wavelength component light, and a long-wavelength component light. The polarization-state adjusting element separately adjusts a polarization state of the central-wavelength component light and each of polarization states of the long-wavelength component light and the short-wavelength component light.

Claims (14)

1. An illumination apparatus comprising:

a light valve configured to modulate a color component light having predetermined wave length; and

a polarization-state adjusting element provided on the light-incident-side of the light valve, wherein

the predetermined wavelength band has a wavelength band (A) and a wavelength band (B) other than the wavelength band (A), and

the polarization-state adjusting element is configured to separately adjust a polarization state of light in the wavelength band (A) and a polarization state of light in the wavelength band (B).

2. The illumination apparatus according to claim 1 , wherein

the polarization-state adjusting element is an edge filter element configured not to adjust the polarization state of light in the wavelength band (A) but to adjust the polarization state of light in the wavelength band (B).

3. The illumination apparatus according to claim 1 , wherein the predetermined wavelength band includes at least a green wavelength band.

4. A projection display apparatus comprising:

a light valve configured to modulate a color component light having predetermined wave length;

projection means configured to project light emitted from the light valve; and

a polarization-state adjusting element provided on the light-incident-side of the light valve, wherein

the predetermined wavelength band has a wavelength band (A) and a wavelength band (B) other than the wavelength band (A), and

the polarization-state adjusting element is configured to separately adjust a polarization state of light in the wavelength band (A) and a polarization state of light in the wavelength band (B).

Assignments (3)
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 →
Priority Claims (1)
JP 2008-206232 · Aug 8, 2008 · national
Continuity (2)
Continuation 12537431 · Aug 7, 2009
Related Publication 20120229772A1 · Sep 13, 2012