Display apparatus

• US 6,547,421 B2
• Filed: 05/29/2001
• Issued: 04/15/2003
• Est. Priority Date: 05/31/2000
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Sugano, Yasuyuki
• Primary Examiner(s): CARIASO, ALAN B
• Application Number:
  US09/867,220
• Publication Number:
  US 20010048560A1
• Time in Patent Office: 686 Days
• Field of Search: 362/19, 362/244-246, 362/268, 362/331, 362/551, 362/561, 362/800, 359/618, 359/619, 359/621-623, 353/20, 353/48, 353/89, 353/94, 353/98
• US Class Current: 362/268
• CPC Class Codes: G02B 27/0905 Dividing and/or superposing multiple light beams
• CPC Class Codes: G02B 27/0927 Systems for changing the beam intensity distribution, e.g. Gaussian to top-hat
• CPC Class Codes: G02B 27/0955 Lenses lenses per se G02B3/00
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: H04N 9/3105 for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators simultaneous projection in colour photography G03B33/10; beam splitting or combining systems per se G02B27/10
• CPC Class Codes: H04N 9/3164 using multiple light sources

Abstract

A video display apparatus which exhibits high utilization efficiency of a luminous flux from a light source and can provide a uniform video. The video display apparatus includes a light source unit including a plurality of coupling optical elements for converting light emitted from a plurality of light sources into a substantially parallel luminous flux and operable to condense light having passed through the coupling optical elements at a predetermined position, an optical integrator for equalizing the intensity distribution of the condensed light, and a light valve.

Claims

1. A video display apparatus comprising:

a light source unit having a plurality of light source sections each having a light source formed from one of a semiconductor light emitting element and a white light lamp and a coupling optical element for converting light emitted from said light source into substantially parallel light, said light source unit including a condenser lens being operable to condense said light from said light source sections having passed through each said coupling optical element at a predetermined focus position on an optical axis of illuminating said video display apparatus, wherein said light source sections are disposed on a plane in said light source unit such that said light from said light source sections is condensed at said predetermined focus position of said condenser lens;

an integrator disposed at the predetermined focus position of said light source unit for equalizing an intra-plane light intensity distribution of said light emitted from said light source unit; and

a light valve of a substantially rectangular shape upon which said light whose intra-plane light intensity distribution has been equalized by said integrator is irradiated, and said light source unit further includes a condenser lens, and said light source sections are disposed on a plane in said light source unit such that said light from said light source sections is condensed at said predetermined focus position by said condenser lens, and

wherein a focal distance of said condenser lens is represented by L, a maximum distance from said optical axis of said video display apparatus to an optical axis of each of said light source sections is represented by H, and said light source unit is designed so as to satisfy a relationship given by;

6. The video display apparatus according to claim 1, wherein said light source is formed from one of a light emitting diode and a laser diode.

7. The video display apparatus according to claim 1, wherein said plurality of light source sections each include a reflecting mirror for respectively reflecting light emitted from said plurality of light source sections in a single direction.

2. A video display apparatus comprising:

a light source unit having a plurality of light source sections each having a light source formed from one of a semiconductor light emitting element and a white light lamp and a coupling optical element for converting light emitted from said light source into substantially parallel light, said light source unit including a condenser lens being operable to condense said light from said light source sections having passed through each said coupling optical element at a predetermined focus position on an optical axis of illuminating said video display apparatus, wherein said light source sections are disposed on a plane in said light source unit such that said light from said light source sections is condensed at said predetermined focus position by said condenser lens;

an integrator disposed at the predetermined focus position of said light source unit for equalizing an intra-plane light intensity distribution of said light emitted from said light source unit; and

a light valve of a substantially rectangular shape upon which said light whose intra-plane light intensity distribution has been equalized by said integrator is irradiated, and said light source unit further includes a condenser lens, and said light source sections are disposed on a plane in said light source unit such that said light from said light source sections is condensed at said predetermined focus position by said condenser lens, and

wherein a maximum value of said light valve in its minor side direction at an angle of said light irradiated on said light valve with respect to said optical axis of said video display apparatus is represented by θ

₁, a maximum value of said light valve in its major side direction is represented by θ

₂, a length of said light valve in its minor side direction is represented by L₁, a length of said light valve in its major side direction is represented by L₂, an effective numerical aperture of said condenser lens is represented by NA_c, and said light source unit is designed such that an area S of light emitting regions of said light source sections satisfies a relationship given by;

4. The video display apparatus according to claim 2, wherein a distance from said light source sections to said predetermined focus position is represented by L, a maximum distance from said optical axis of said video display apparatus to an optical axis of each of said light source sections is represented by H, and said light source unit is designed so as to satisfy a relationship given by:

3. A video display apparatus comprising:

a light source unit having a plurality of light source sections each having a light source formed from one of a semiconductor light emitting element and a white light lamp and a coupling optical element for converting light emitted from said light source into substantially parallel light, said light source unit being operable to condense said light from said light source sections having passed through each said coupling optical element at a predetermined focus position;

an integrator disposed at the predetermined focus position of said light source unit for equalizing an intra-plane light intensity distribution of said light emitted from said light source unit; and

a light valve of a substantially rectangular shape upon which said light whose intra-plane light intensity distribution has been equalized by said integrator is irradiated,

wherein said light source sections are disposed on a semi-sphere centered at said predetermined focus position so that said light from said light source sections is condensed at said predetermined focus position.

5. The video display apparatus according to claim 3, wherein a maximum value of said light valve in its minor side direction at an angle of said light irradiated on said light valve with respect to said optical axis of said video display apparatus is represented by θ

₁, a maximum value of said light valve in its major side direction is represented by θ

₂, a length of said light valve in its minor side direction is represented by L₁, a length of said light valve in its major side direction is represented by L₂, a distance from said light source sections to said predetermined focus position is represented by L, a maximum distance from said optical axis of said video display apparatus to an optical axis of each of said light source sections is represented by H, and said light source unit is designed so that an area S of light emitting regions of said light source sections satisfies a relationship given by;

8. A video display apparatus comprising:

a light source unit having a plurality of light source sections each having a light source formed from one of a semiconductor light emitting element and a white light lamp and a coupling optical element for converting light emitted from said light source into substantially parallel light, said light source unit having a condenser lens to condense said light from said light source sections having passed through each said coupling optical element at a predetermined focus position on an optical which said light whose intra-plane light intensity distribution has been equalized by said integrator is irradiated,

wherein said light source sections are disposed on a semi-sphere centered at said predetermined focus position so that said light from said light source sections is condensed at said predetermined focus position.

9. A video display apparatus comprising:

a light source unit having a plurality of light source sections each having a light source formed from one of a semiconductor light emitting element and a white light lamp and a coupling optical element for converting light emitted from said light source into substantially parallel light, said light source unit having a condenser lens to condense said light from said light source sections having passed through each said coupling optical element at a predetermined focus position on an optical axis of illuminating said video display apparatus;

an integrator disposed at the predetermined focus position of said light source unit for equalizing an intra-plane light intensity distribution of said light emitted from said light source unit;

a light valve of a substantially rectangular shape upon which said light whose intra-plane light intensity distribution has been equalized by said integrator is irradiated, and

a polarization conversion element disposed at one of a position between said light source unit and said integrator, a position inside said integrator, and a position between said integrator and said light valve.