Image display device and light source device

• US 7,354,157 B2
• Filed: 08/04/2006
• Issued: 04/08/2008
• Est. Priority Date: 08/12/2005
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Takeda, Takashi, Yonekubo, Masatoshi
• Primary Examiner(s): BLACKMAN, ROCHELLE ANN J
• Application Number:
  US11/462,570
• Publication Number:
  US 20070035723A1
• Time in Patent Office: 613 Days
• Field of Search: 353/30, 353/31, 353/34, 353/37, 353/81, 353/82, 353/84, 353/98, 353/99, 353/102, 359/27, 359/326, 359/328, 359/331, 359/618, 359/629, 359/634, 348/67, 348/E9.026, 348/739, 348/742, 348/744, 348/750, 348757-759, 348/771, 349/5, 349/7, 349/8, 362/553, 362/259, 372/22, 372/23, 372/25, 372/26, 372/28, 372/29.02, 372/29.023, 372/30, 372/32
• US Class Current: 353/30
• CPC Class Codes: H04N 9/3129 scanning a light beam on the display screen scanning a light beam on a screen in displays other than projection devices G09G3/02; scanning systems in general G02B26/10; projectors using laser light sources in general H04N9/3161

Abstract

An image display device includes a laser light source, a wavelength conversion element converting a wavelength of a light beam emitted from the laser light source into a predetermined wavelength, and a light modulating device modulating the laser beam output from the wavelength conversion element, wherein the laser beam emitted from the laser light source has a frequency of integral multiplication of the maximum modulation frequency of the light modulating device, and has a pulse width narrower than a time period during which the light modulating device is in a stable state.

Claims

1. An image display device comprising:

a laser light source;

a wavelength conversion element converting a wavelength of a laser beam emitted from the laser light source into a predetermined wavelength; and

a light modulating device modulating the laser beam output from the wavelength conversion element,

wherein the laser beam emitted from the laser light source has a frequency of integral multiplication of the maximum modulation frequency of the light modulating device, and has a pulse width narrower than a time period during which the light modulating device is in a stable state, and

wherein a pulsed emission of the laser beam is performed while the light modulating device is in the stable state.

2. The image display device according to claim 1 wherein the laser beam emitted from the laser light source has emission timing synchronized with timing of the minimum drive period of the light modulating device.

3. The image display device according to claim 1 wherein a duty ratio of a pulse of the laser beam emitted from the laser light source is no greater than fifty percent.

4. The image display device according to claim 1 wherein two or more of pulses of the laser beam are emitted in the minimum drive period of the light modulating device, and the pulse width in emitting two or more pulses of the laser beam is narrower than the pulse width in emitting only one pulse of the laser beam.

7. The image display device according to claim 1, wherein the light modulating device includes a plurality of mirror devices.

5. A light source device for use with an image display device, the image display device including:

a laser light source,

a wavelength conversion element converting a wavelength of a laser beam emitted from the laser light source into a predetermined wavelength, and

a light modulating device modulating the laser beam output from the wavelength conversion element,

wherein the laser beam emitted from the laser light source has a frequency of integral multiplication of the maximum modulation frequency of the light modulating device, and has a pulse width narrower than a time period during which the light modulating device is in a stable state, and

wherein a pulsed emission of the laser beam is performed while the light modulating device is in the stable state.

6. The light source device according to claim 5 wherein the laser beam emitted from the laser light source has emission timing synchronized with timing of the minimum drive period of the light modulating device.