Projection display apparatus

Patent metadata

Field	Value
Publication number	US-9740014-B2
Application number	US-201615004087-A
Country	US
Kind code	B2
Filing date	Jan 22, 2016
Priority date	Jan 30, 2015
Publication date	Aug 22, 2017
Grant date	Aug 22, 2017

Abstract

A projection display apparatus includes: a laser light source which emits a blue light; a wheel which includes a light emitting body provided on a reflection surface of a substrate, the light emitting body emitting an emission light when the emitting body is irradiated with the blue light; a bandpass filter which is disposed on an optical path on which the emission light of the light emitting body travels; a plurality of optical modulating elements which modulate the blue light and the emission light from the light emitting body; and a projection unit which projects the light modulated by the plurality of optical modulating elements. The bandpass filter allows transmission of part of lights whose wavelength bands are 560 nm to 590 nm in the emission light of the light emitting body, and reflects other lights.

First claim

What is claimed is:

1. A projection display apparatus comprising:
a laser light source which emits a blue light;
a wheel which includes a light emitting body provided on a reflection surface of a substrate, the light emitting body emitting an emission light when the emitting body is irradiated with the blue light;
a bandpass filter which is disposed on an optical path on which the emission light of the light emitting body travels;
a plurality of optical modulating elements which modulate the blue light and the emission light from the light emitting body;
a projection unit which projects the light modulated by the plurality of optical modulating elements; and
a combining optical element which combines the emission light and the blue light to emit a combined light,
wherein the bandpass filter allows transmission of part of lights whose wavelength bands are 560 nm to 590 nm in the emission light of the light emitting body, and reflects other lights and is disposed on the optical path on which an emission light from the combining optical element travels.

2. The projection display apparatus according to claim 1 , further comprising a split optical unit including two dichroic mirrors which split the blue light and the emission light from the light emitting body into a red image light, a green image light and a blue image light.

3. The projection display apparatus according to claim 2 , wherein a wavelength in which a transmittance in a transmission wavelength band of the bandpass filter is maximized is shorter than a cutoff wavelength at which transmittance is 50% of a dichroic mirror surface, which splits the red image light and the green image light, of the split optical unit.

4. The projection display apparatus according to claim 3 , wherein a dominant wavelength of the blue image light falls within a range from 460 nm to 470 nm.

5. The projection display apparatus according to claim 4 , wherein a half-maximum wavelength of short wavelength side in an emission spectrum of the light emitting body is shorter than a cutoff wavelength at which transmittance is 50% of a dichroic mirror surface, which splits the green light and the blue light, of the split optical unit.

6. The projection display apparatus according to claim 5 , wherein a dominant wavelength of the laser light source is 460 nm or shorter.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Okuda Michihiro

Classifications

• H04N9/3158

  for controlling the spectrum · CPC title

• G03B21/2013

  Plural light sources · CPC title

• H04N9/3161

  using laser light sources (using laser beams scanning the display screen H04N9/3129) · CPC title

• G02B27/141 Primary

  using dichroic mirrors · CPC title

• G03B21/204

  using secondary light emission, e.g. luminescence or fluorescence (using different colours G03B33/00; if related to video signals H04N9/3197) · CPC title