Method of illumination and display apparatus

1. A display apparatus comprising:

a light source, emitting light;

a light valve, having a screen formed of a plurality of pixels;

a light cross-section converter, receiving the light from said light source and converting the received light into illumination light having a cross section enough to illuminate at least one of the plurality of pixels at a time; and

a light scanning mechanism, controlling a direction of travel of the illumination light in such a way that the illumination light scans the plurality of pixels;

wherein said light scanning mechanism includes a light scanning mechanism controller that controls at least one of a sequence, a speed, and a number of times of scanning where the illumination light scans the plurality of pixels, in such a way that a desired profile of distribution of illuminance is obtained over an entire surface of the screen for a time period not longer than one frame time of an image, and

wherein said light scanning mechanism controller controls the desired profile of distribution of illuminance in accordance with a type of input signal or an application of the display apparatus.

2. The display apparatus according to claim 1 , wherein at least a part of a profile of light distribution of light intensity in a cross section of the illumination light has a shape of a Gaussian beam.

3. The display apparatus according to claim 2 , wherein said scanning mechanism controls scanning intervals at which the illumination light scans said light valve, the scanning intervals being greater than a Gauss radius.

4. The display apparatus according to claim 2 , wherein said scanning mechanism controls scanning intervals at which the illumination light scans the plurality of pixels of said light valve, the scanning intervals being ½ of a Gauss radius.

5. The display apparatus according to claim 2 , wherein the scanning intervals at which the illumination light scans the plurality of pixels of said light valve are equal to a Gauss radius.

6. The display apparatus according to claim 2 , wherein scanning intervals at which the illumination light scans the plurality of pixels of said light valve are varied in accordance with a type of the image.

7. The display apparatus according to claim 1 , wherein at least a part of a profile of distribution of light intensity across the entire surface of the screen has a shape of a Gaussian beam.

8. The display apparatus according to claim 1 , further comprising a projector that receives the illumination light exiting said light valve and projects the received illumination light onto an object;

wherein said light scanning mechanism controls scanning intervals at which the illumination light scans the plurality of pixels of said light valve, the scanning intervals being controlled in such a way that a light-incident surface of the object has a desired profile of distribution of illuminance and a light-exiting surface of the object has a desired profile of distribution of light intensity.

9. The display apparatus according to claim 8 , wherein said light valve is a reflection type light valve in which the plurality of pixels are arranged in a flat plane;

wherein said projector is disposed opposite to said light valve with said scanning mechanism positioned between said projector and said light valve;

wherein said scanning mechanism has a transparent medium disposed between said light valve and said projector and causes the illumination light that exits said light cross-section converter to be incident on the plurality of pixels of said light valve;

wherein the plurality of pixels reflect the illumination light received from said scanning mechanism to said projector through the transparent medium.

10. The display apparatus according to claim 9 , wherein said scanning mechanism further includes a light recovery section that recovers a portion of the illumination light for reuse, the recovered portion of the illumination light being reflected by the plurality of pixels but does not form an image,

wherein the illumination light recovered by the light recovery section is combined with the illumination light that illuminates said light valve.

11. The display apparatus according to claim 9 , further comprising an aperture member through which image-forming light passes, the image forming light being a portion of illumination light reflected from said light valve.

12. The display apparatus according to claim 8 , wherein said light valve is a transmissive type that has a first surface and a second surface between which the plurality of pixels are arranged in a flat plane;

wherein said projector is disposed opposite to the first surface of the light valve;

wherein said scanning mechanism is disposed opposite to the second surface of the light valve, receives the illumination light from the light cross-section converter, and causes the illumination light to scan the plurality of pixels of said light valve in such a way that the illumination light passes through the plurality of pixels.

13. The display apparatus according to claim 12 , wherein said scanning mechanism includes a mirror having a reflecting surface that reflects the illumination light to said light valve,

wherein said scanning mechanism causes the reflecting surface to move substantially from a first one of first two opposite sides of said light valve to a second one of the first two opposite sides so that the illumination light scans the plurality of pixels in a first direction.

14. The display apparatus according to claim 13 , wherein the mirror is a concave mirror having a reflecting surface that describes a spiral,

wherein said scanning mechanism causes the concave minor to rotate so that the reflecting surface moves from the first one of the second two opposing sides to the second one of the second two opposing sides.

15. The display apparatus according to claim 14 , wherein the reflecting surface describes a quadratic curve,

wherein said scanning mechanism causes the illumination light to emit from a focal point of the quadratic curve toward the reflecting surface.

16. The display apparatus according to claim 14 , wherein when the mirror moves, the mirror agitates air near said light valve to create a flow of air to minimize temperature rise of said light valve.

17. The display apparatus according to claim 13 , further comprising an aperture member having an opening formed therein,

wherein image-forming light passes through the opening, and non-image-forming light is absorbed into the aperture member,

wherein the opening is moved substantially from a first one of two opposite sides of said light valve to a second one of the two opposite sides so that the illumination light scans the plurality of pixels.

18. The display apparatus according to claim 13 , wherein said scanning mechanism causes the illumination light to move from a first one of second two opposite sides of said light valve to a second one of the second two opposite sides so that the illumination light scans the plurality of pixels in a second direction.

19. The display apparatus according to claim 12 , further comprising an aperture member through which image-forming light passes, the image forming light being a portion of illumination light reflected from said light valve.

20. The display apparatus according to claim 1 , wherein the light valve is scanned with the illumination light having a higher profile of distribution of intensity in the middle portion of the screen than in the peripheral portion of the screen if the input signal is a television signal.

21. The display apparatus according to claim 1 , wherein the light valve is scanned with the illumination light having uniform intensity across the entire surface of the screen if the input signal is a computer display signal.