Abstract: A projection optical system for enlarging and projecting a light flux from an image display panel modulating an irradiation light, onto a screen in an oblique direction, the projection optical system includes: a lens system including a plurality of lenses, the lens system refracting the light flux from the image display panel; a single convex mirror reflecting the light flux from the lens system, the lens system and the convex mirror being arranged in an order from the image display panel; and a stop disposed in an optical path after an emission from the lens system to an incidence on the convex mirror.

Abstract: According to the present invention, an image projector includes a reflecting light valve, a group of refracting lenses forming a projecting optical system that enlarges and projects an optical image given from the light valve, a power mirror having a power and forming the projecting optical system together with the group of refracting lenses, and a transmissive screen for displaying the optical image that is given from the light valve and enlarged by the projecting optical system, wherein the exit pupil position is set such that the minimum angle of view ?min exceeds 40°, and the Petzval partial sum of lenses is set larger than a value determined by the minimum angle of view.

Abstract: An image projection apparatus includes an image processing device, an illuminating device, a light valve, and a projection optical system; wherein the projection optical system is formed in such a way that at least one of a first deviation corresponding to an amount of the magnification chromatic aberration of a light having a central wavelength of the red light relative to the green light and a second deviation corresponding to an amount of the magnification chromatic aberration of the blue light relative to the green light is larger than a fixed-pixel pitch, and a third deviation corresponding to an amount of the magnification chromatic aberration of a light having a maximum wavelength of the red light relative to a light having a minimum wavelength of the red light is not larger than the fixed-pixel pitch; wherein the first deviation and/or the second deviation is eliminated by supplying the compensated video signal to the light valve.

Abstract: A light diffusion element includes a liquid-crystal diffusion layer that variably diffuses an amount of light depending on an applied voltage, a first electrode that is laid on a plane of the light diffusion layer and made of a first and a second segmented-electrodes, a second electrode that is laid on the other plane of the light diffusion layer, a voltage applying unit that generates and applies two types of voltages, and a voltage changing unit that varies the two types of voltages. One of the voltages is applied between the first segmented-electrodes and the second electrode, and the other between the second segmented-electrodes and the second electrode. Both the segmented-electrodes are included in each pixel.

Abstract: A light diffusion element includes a light diffusion layer that contains at least two types of liquid crystal molecules each having a different light scattering characteristic defined by a voltage and a refractive index. A pair of electrodes sandwiches the light diffusion layer, an applying unit generates and applies a variable voltage to the pair of electrodes, and a voltage changing unit varies the voltage generated by the applying unit. The voltage changing unit varies the voltage such that each of the refractive indexes of the liquid crystal molecules in the light diffusion layer changes temporally.

Abstract: In a projection type display apparatus includes an illumination device (including a light source), a light modulation element, a projection optical system that projects a modulated light from the light modulation element, and a screen onto which a projected light is projected. The projection optical system includes a refraction type optical system that refracts the modulated light from the light modulation element, and a hologram element disposed on a position remote from the screen and shifted in a direction parallel to the screen from a center of the screen. The hologram element projects the modulated light having passed through the refraction type optical system onto the screen so that a light ray of the center of the modulated light is inclined with respect to a normal line of the screen.

Abstract: According to the present invention, an image projector includes a reflecting light valve, a group of refracting lenses forming a projecting optical system that enlarges and projects an optical image given from the light valve, a power mirror having a power and forming the projecting optical system together with the group of refracting lenses, and a transmissive screen for displaying the optical image that is given from the light valve and enlarged by the projecting optical system, wherein the exit pupil position is set such that the minimum angle of view ? min exceeds 40°, and the Petzval partial sum of lenses is set larger than a value determined by the minimum angle of view.