Projector and image display method

1. A projector comprising:

first to third display elements each of which spatially modulates incident light to display an image;

a first light source unit that includes a red light source that emits red light having a peak wavelength in a red wavelength band, the red light emitted from the red light source being applied to the first display element;

a second light source unit that includes a first green light source that emits first green light having a peak wavelength in a green wavelength band, the first green light emitted from the first green light source being applied to the second display element;

a third light source unit that includes a second green light source that emits second green light having a peak wavelength in the green wavelength band and a blue light source that emits blue light having a peak wavelength in a blue wavelength band, the second green light emitted from the second green light source and the blue light emitted from the blue light source being applied on the same optical path to the third display element;

a color synthesizing means unit that synthesizes the images displayed by the first to third display elements;

a projection lens that projects the image synthesized by the color synthesizing unit; and

a control unit that controls, based on an input video signal, display operations of the first to third display elements and lighting operations of the red light source, the first and second green light sources, and the blue light source,

wherein the control unit lights, for a predetermined period, the red light source and the first green light source to display a red image based on the input video signal by the first display element and a green image based on the input video signal by the second display element,

wherein the control unit lights, for a first period, the second green light source to display the green image by the third display element, and lights, for a second period, the blue light source to display a blue image based on the input video signal by the third display element, the first and second periods being provided by dividing the predetermined period with a predetermined ratio, and

wherein the second and third display elements simultaneously display the green image during the first period.

2. The projector according to claim 1 , wherein the third light source unit includes a dichroic mirror for synthesizing the green light from the second green light source and the blue light from the blue light source.

3. The projector according to claim 1 , wherein the third light source unit includes an optical element for synthesizing the green light from the second green light source and the blue light from the blue light source.

4. A projector comprising:

first to third display elements each of which spatially modulates incident light to display an image;

a first light source unit that includes a blue light source that emits blue light having a peak wavelength in a blue wavelength band, the blue light emitted from the blue light source being applied to the first display element;

a second light source unit that includes a first green light source that emits first green light having a peak wavelength in a green wavelength band, the first green light emitted from the first green light source being applied to the second display element;

a third light source unit that includes a second green light source that emits second green light having a peak wavelength in the green wavelength band and a red light source that emits red light having a peak wavelength in a red wavelength band, the second green light emitted from the second green light source and the red light emitted from the red light source being applied on the same optical path to the third display element;

a color synthesizing unit that synthesizes the images displayed by the first to third display elements;

a projection lens that projects the image synthesized by the color synthesizing unit; and

a control unit that controls, based on an input video signal, display operations of the first to third display elements and lighting operations of the red light source, the first and second green light sources, and the blue light source,

wherein the control unit lights, for a predetermined period, the blue light source and the first green light source to display a blue image based on the input video signal by the first display element and a green image based on the input video signal by the second display element,

wherein the control unit lights, for a first period, the second green light source to display the green image by the third display element, and lights, for a second period, the red light source to display a red image based on the input video signal by the third display element, the first and second periods being provided by dividing the predetermined period with a predetermined ratio, and

wherein the second and third display elements simultaneously display the green image during the first period.

5. The projector according to claim 4 , wherein the third light source unit includes a dichroic mirror for synthesizing the green light from the second green light source and the red light from the red light source.

6. The projector according to claim 4 , wherein the third light source unit includes an optical element for synthesizing the green light from the second green light source and the red light from the blue light source.

7. The projector according to claim 1 , wherein the red light source, the first and second green light sources, and the blue light source comprise solid light sources.

8. The projector according to claim 1 ,

wherein each of the first and second green light sources includes:

an excitation light source for emitting excitation light; and

a phosphor excited by the excitation light from the excitation light source to emit green fluorescence.

9. An image display method implemented in a projector that includes first to third display elements each of which spatially modulates incident light to display an image, synthesizes the images displayed by the first to third display elements, and projects the synthesized image,

the method comprising:

irradiating, for a predetermined period, the first display element with red light having a peak wavelength in a red wavelength band to display a red image based on an input video signal by the first display element;

irradiating, for the predetermined period, the second display element with first green light having a peak wavelength in a green wavelength band to display a green image based on the input video signal by the second display element;

irradiating, for a first period, the third display element with second green light having a peak wavelength in the green wavelength band to display the green image by the third display element, and irradiating, for a second period, the third display element with blue light having a peak wavelength in the blue wavelength band on the same optical path as that of the second green light to display a blue image based on the input video signal by the third display element, the first and second periods being provided by dividing the predetermined period with a predetermined ratio; and

displaying the green image during the first period simultaneously on the second and third display elements.

10. An image display method implemented in a projector that includes first to third display elements each of which spatially modulates incident light to display an image, synthesizes the images displayed by the first to third display elements, and projects the synthesized image,

the method comprising:

irradiating, for a predetermined period, the first display element with blue light having a peak wavelength in a blue wavelength band to display a blue image based on an input video signal by the first display element;

irradiating, for the predetermined period, the second display element with first green light having a peak wavelength in a green wavelength band to display a green image based on the input video signal by the second display element;

irradiating, for a first period, the third display element with second green light having a peak wavelength in the green wavelength band to display the green image by the third display element, and irradiating, for a second period, the third display element with red light having a peak wavelength in the red wavelength band on the same optical path as that of the second green light to display a red image based on the input video signal by the third display element, the first and second periods being provided by dividing the predetermined period with a predetermined ratio; and

displaying the green image during the first period simultaneously on the second and third display elements.

11. The projector according to claim 4 , wherein the red light source, the first and second green light sources, and the blue light source comprise solid light sources.

12. The projector according to claim 4 ,

wherein each of the first and second green light sources includes:

an excitation light source for emitting excitation light; and

a phosphor excited by the excitation light from the excitation light source to emit green fluorescence.

13. The projector according to claim 1 , wherein the peak wavelength in the green wavelength band of the first green light and the peak wavelength in the green wavelength band of the second green light are substantially equal.

14. The projector according to claim 1 , wherein the control unit lights the second green light source to display the green image by the third display element for half of the predetermined period.

15. The projector according to claim 1 , wherein the first and second periods are equal.

16. The projector according to claim 1 , wherein light emission area of each of the red light source, the first and second green light sources, and the blue light source is set to be a maximum area within an area range satisfying restrictions of etendue.

17. The projector according to claim 1 , wherein the predetermined ratio is set according to a white balance output.