Abstract: A projection display apparatus includes a light valve, a light source for producing light directed to the light valve, an integrator lens disposed in an optical path extending from the light source to the light valve and including a first lens array and a second lens array, and a light amount adjustment mechanism disposed in the optical path between the first lens array and the second lens array. The light amount adjusting mechanism includes a pair of light shielding elements pivoting in the form of a pair of double doors. The pair of light shielding elements have an opening formed in a region of tip portions thereof which corresponds to lens cells in contact with the optical axis of the second lens array. A region of the opening corresponding to one lens cell in contact with the optical axis of the second lens array is of a triangular configuration.

Abstract: A projection display apparatus 101 in which the light quantity adjusting means has a simple and readily interchangeable structure, and which can improve image quality by adjusting the quantity of light received by a light valve continuously, without causing illuminance irregularities, and without having unwanted light radiated onto the screen, the light quantity adjusting means 9 having light blocking members 91L, 91R for blocking light in transit to a second lens array 22, and rotational axes 91LA, 91RA for turnably supporting each of the light blocking members on an xy plane, the light blocking members 91L, 91R and rotational axes 91LA, 91RA being positioned so that the rotational axes 91LA, 91RA are disposed in positions symmetric with respect to the optical axis AX on the xy plane, and the turning range from the light blocking initiation position at which the light blocking members 91L, 91R, by being turned, start to block light in transit toward the second lens array 22 to the maximum light blocking posi

Abstract: A liquid crystal rear projector device of the present invention includes a lamp unit providing a light source, a cooling fan for cooling the lamp unit, and an optical system for generating color image light with the lamp unit providing a light source, the lamp unit including a light emitting tube providing a light source, and a reflector for reflecting light emitted from the light emitting tube toward the optical system. The reflector has an air introduction hole for introducing air discharged from the cooling fan into the reflector, which is provided near the spherical portion of the light emitting tube, and faces to a vertical top of the spherical portion to blow the air to the top.

Abstract: The illumination optical system for guiding a light emitted from a light source to an object to be illuminated along an optical path includes a first reflecting mirror reflecting a part of a light which is moving in a forward direction along the optical path to move away from the light source and a second reflecting mirror reflecting a part of a light which is reflected from the first reflecting mirror and moving in a reverse direction along the optical path to approach the light source. The first reflecting mirror has an opening facing a light-entering surface of the object to be illuminated, and the second reflecting mirror has a window that allows the light emitted from the light source to pass therethrough, whereby an optical cavity is constituted by the first and second reflecting mirrors.

Abstract: An apparatus for controlling the light intensity output from an arc lamp for use with an arc lamp-illuminated projector includes a light valve to control the projector output light intensity by the selective positioning of the light valve in all or a portion of the light path between the arc lamp and the projector output. The light valve is operatively coupled to the output of a magnetically coupled clutch, the input of the clutch being continuously driven by a motor. A programmer applies a voltage proportional to the desired light intensity to the clutch for controlling the degree of magnetic coupling, and therefore the position of the light valve. The variable torque applied through the clutch to the light valve may be countered by a variable counter-torque produced as by a spring to establish the desired continuous range of equilibrium positions of the light valve.

Abstract: A series of slides are placed in a vertical loader and are movable alternatively into respective ones of two projection positions. Each slide is moved laterally of the loader by a carriage, then pushed to the projection position by a push rod. During projection the following slide in the loader is similarly moved to the other projection position. After its projection, the first slide is brought back by a further push rod to its carriage and then is moved by the carriage to be deposited in a receptacle and be replaced by a new slide which will be moved into the same projection position.

Abstract: A photographic film projection system includes a plurality of projectors, one of which is an arc lamp projector, and a dissolver instrument whose controlled output power to the arc lamp projector is a phase controlled average a.c. power. The arc lamp projector has a light valve comprising a motor means linearly responsive to average power, for example, a moving iron galvanometer, and a movable means, such as a louvre, positioned between the arc lamp and the film gate.

Abstract: The present invention relates to a projector comprising two optical systems enabling transparencies to be projected with cross-fading, in 3-D and with double-width panning, said projector operating with a single transparency distributing and recuperating magazine, in which the transparencies are arranged in the same order as if they were to pass in a single-lens projector; said projector comprises four parallel transparency guide slots, which are parallel to one another and transverse with respect to the axes of two optical systems in which the transparencies circulate in pairs, said guide slots being extended by a switching means whose role is to cause the transparencies which have already been projected to pass from the forward guide slots into the return guide slots, and thus to cause the transparencies to return to the same compartment of the same magazine from which they left. These displacements are possible due to a recuperator having multiple functions.

Abstract: A photographic film projection system includes a plurality of projectors, one of which is an arc lamp projector, and a dissolver instrument whose controlled output power to the arc lamp projector is a phase controlled average a.c. power. The arc lamp projector has a light valve comprising a motor means linearly responsive to average power, for example, a moving iron galvanometer, and a movable means, such as a louvre, positioned between the arc lamp and the film gate.