Maxell, Ltd.

Hitachi Maxell, Limited

Eiki Ishijima

Shinro Inui

Nobuki Matsui

Hidemi Yamada

Hiroshi Oshima

A projection-type video display apparatus includes: light sources, an illumination optical system, a display element, and a projection optical system. The illumination optical system includes: a mirror that reflects the illumination light toward the display element; a lens that is placed between the mirror and the display element on an optical path of the illumination light; a mirror angle adjustment mechanism that adjusts an angle of the mirror; a light-shielding plate that blocks unwanted light which is a portion of the illumination light reflected off the mirror toward the display element via the lens; and a light-shielding plate movable mechanism that is able to move the light-shielding plate between a first position to block the unwanted light and a second position to permit the unwanted light to illuminate the display element.

Projection-type video display apparatus

A lens shift mechanismof the projection-type image display deviceincludes a horizontal movable basefor horizontally shifting a projection lens, a vertical movable basefor vertically shifting the projection lens, and a horizontal drive actuatorand a vertical drive actuatorfor driving these bases. Driving forces of these actuatorsare transmitted via respective lead screws() and a pair of lead nuts() meshing with the lead screws to shift the bases. A pair of lead nuts are installed with elastic bodies() applying a pressure such that the pair of lead nuts recede from or approach each other in the axial direction of the lead screw. In this configuration, a delay in the shift operation is removed by reducing a backlash in the lens movement.

Projection-type image display device

Lamp for projector

Growing community of inventors

Ibaraki, Japan

Eiki Ishijima