Projection apparatus and image projection changeover method

• US 20090033885A1
• Filed: 10/01/2008
• Published: 02/05/2009
• Est. Priority Date: 11/01/2003
• Status: Active Grant

• Current Assignee: Ignite USA (Ignite)
• Original Assignee: Olympus Corporation, Silicon Quest Kabushiki-Kaisha
• Inventors: Shirai, Akira, Ishii, Fusao
• Granted Patent: US 8,061,856 B2
• Time in Patent Office: Days
• US Class Current: 353/85
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G02B 27/141 using dichroic mirrors
• CPC Class Codes: G03B 21/008 using micromirror devices
• CPC Class Codes: G03B 21/2033 LED or laser light sources
• CPC Class Codes: G03B 33/06 by additive-colour projection apparatus
• CPC Class Codes: G03B 33/12 using beam-splitting or beam-combining systems, e.g. dichroic mirrors
• CPC Class Codes: H04N 2005/7466 Control circuits therefor
• CPC Class Codes: H04N 9/3155 for controlling the light source light source control per se H05B35/00 – H05B47/00; control of an illumination source for displays in general G09G3/3406

Abstract

The present invention provides a projection apparatus, comprising: a light source; a spatial light modulator for modulating the incident light emitted from the light source; a spatial light modulator control unit for generating, from an inputted image signal, a control signal for driving the spatial light modulator; and a light source control unit for receiving data corresponding to the control signal for controlling the light source to operate in one of three states consisted of a driven state, a stopped state and a standby state on the basis of the data.

Claims

1. A projection apparatus, comprising:

a light source;

a spatial light modulator for modulating the incident light emitted from the light source;

a spatial light modulator control unit for generating, from an inputted image signal, a control signal for driving the spatial light modulator; and

a light source control unit for receiving data corresponding to the control signal for controlling the light source to operate the light source in a driven state, a stopped state and a standby state on the basis of the data.

2. The projection apparatus according to claim 1, wherein:

the light source control unit controls the light source to operate in the standby state for either controlling the light source to stop projecting the incident light while driven or to project the incident light for not projecting and displaying a visible image by said projection apparatus.

3. The projection apparatus according to claim 1, wherein:

the light source control unit controls the light source to perform a pulse emission.

4. The projection apparatus according to claim 1, wherein:

the light source further comprises a laser diode or a light emitting diode.

5. The projection apparatus according to claim 1, wherein:

the spatial light modulator comprises a plurality of mirror elements each for reflecting and controlling a reflecting direction of the incident light.

6. The projection apparatus according to claim 1, wherein:

the light source control unit controls the intensity of the incident light in the standby state.

7. The projection apparatus according to claim 1, wherein:

the light source control unit controls the light source by applying a drive current for operating the light source in the standby state wherein the drive current is smaller than a drive current for the drive state and greater than the drive voltage for the stopped state.

8. The projection apparatus according to claim 1, wherein:

the light source control unit controls the light source to apply a drive voltage to operate the light source in the standby state wherein the drive voltage is smaller than a drive voltage for the drive state and greater than the drive voltage for the stopped state.

9. The projection apparatus according to claim 1, wherein:

the amount of light emitted from the light source within a period corresponding to a least significant bit (LSB) of the data in the standby state is no greater than an amount of light required for displaying an image element with a gray scale represented by the LSB.

10. The projection apparatus according to claim 3, wherein:

the light source control unit controls the pulse emission of the light source for operating the projection apparatus in the driven state or the standby state.

11. The projection apparatus according to claim 1, wherein:

the light source control unit controls the light source to operate in the standby state within a period other than a period of operating in the driven state.

12. The projection apparatus according to claim 1, wherein:

the light source includes a red light source, a green light source and a blue light source, wherein the light source control unit controls the red light source, green light source and blue light source to independently operate in the standby state.

13. An image projection changeover method for switching between projecting an image and not projecting an image by controlling a light source, comprising the steps of receiving a control signal for controlling the light source;

and

controlling the light source for switching between projecting an image and not projecting an image under

a first state for the light source outputting light at an intensity ready for projecting an image and

a second state for the light source outputting light at an intensity for not projecting an image

or a third state for controlling the light source for not projecting a light while providing an electric power to the light source when an image is not projected on the basis of the control signal.

14. The image projection changeover method according to claim 13, wherein:

the light source emits a light no more than an amount of light required for displaying an image element at a gray scale represented by the least significant bit (LSB) within a period corresponding to the LSB of the control signal in the second state.

15. The image projection changeover method according to claim 13, wherein:

the light source further comprises a semiconductor light source.

16. The image projection changeover method according to claim 13, wherein:

the light source includes a light source or sources with at least three primary colors of light, wherein the light source is controlled for suppress an projection of the image when the colors of the light source(s) are changed over.

17. A projection apparatus, comprising:

a light source;

a spatial light modulator for modulating the light emitted from the light source;

an electric current supplier for supplying the light source with an electric current;

a plural switches disposed and interconnected in parallel between the light source and electric current supplier; and

a light source control circuit for independently controlling the switches by controlling the electric current supplier in accordance with the control state of the spatial light modulator.

18. The projection apparatus according to claim 17, further comprising:

a second switch disposed between the light source and switches for changing over between an active state with the electric current supplier electrically connected to the light source and an inactive state with the electric current supplier electrically disconnected to the light source.

19. The projection apparatus according to claim 17, further comprising:

a second electric current supplier connected to the light source, wherein the light source emits light of an amount no greater than an amount required for displaying an image element of a gray scale represented by a least significant bit (LSB) within a period corresponding to the LSB representing a minimum unit of modulation for the spatial light modulator when the electric current supplier supplies the electric current and also the second switch is in the inactive state.

20. The projection apparatus according to claim 19, wherein:

the light source is controlled for not projecting an with the light modulated by the spatial light modulator when the electric current supplier supplies the electric current and also the second switch is in the inactive state.

21. The projection apparatus according to claim 17, wherein:

the electric current supplier is disposed near the light source.

22. The projection apparatus according to claim 17, wherein

the switch is disposed in the vicinity of the light source.

23. The projection apparatus according to claim 17, further comprising:

a board, wherein the electric current supplier and the switch are mounted onto the board.

24. The projection apparatus according to claim 17, further comprising:

a board, wherein the board is connected to a cooling means also for cooling the light source.

25. The projection apparatus according to claim 17, wherein:

the light source is a semiconductor light source arranged as an array.

26. The projection apparatus according to claim 25, wherein:

a plurality of control units for controlling the semiconductor light source comprising at least two of the switches.