A projector has an illumination optical system, a reflection-type display panel, a projection optical system, and light-introducing device. The display panel is illuminated by the illumination light emitted from the illumination optical system and is divided into a plurality of pixels to reflect the incoming illumination light selectively in accordance with the pattern formed by those pixels and thereby produce projection light. The projection optical system transmits the projection light reflected from the display panel to project the pattern formed by the pixels onto a projection plane on which to form a projected image, and is composed of, from the projected-image side, a front lens unit, an aperture stop, and a rear lens unit. The light-introducing device is disposed between the front and rear lens units and directs the illumination light to the display panel. The projection optical system fulfills the condition where .gamma.F represents the angular magnification of the front lens unit.
Abstract Focusing system of the light beam for a videoprojector or comprising at least an image microforming device DMD (Digital Micromirror Device); the main feature of the system consisting in that it comprises at least an aspheric lens associated to at least an achromatic doublet. This configuration allows a substantial reduction of chromatic aberration, spherical aberration, curvature of field and the distortions, obtaining a more homogeneous illumination of the image microforming device.
A projection optical system projects an enlarged image of a light valve image onto a screen. The system has, from the conjugate enlargement side: a negative front lens unit, optical path turning means (including a reflecting surface), a positive rear lens unit, and projection light preparing means, which can separate illumination and projection light, or can integrate light of different colors, or can do both. Each of the front and rear lens units includes at least one aspherical surface. The front lens unit has a negative first lens element at its conjugate-enlargement end and a negative second lens element at the conjugate reduction side of the first lens element. The rear lens unit includes a positive third lens element made of an anomalous dispersion material. The center of the light valve is not located on the optical axis of the rear lens unit.
In a projection device including a reflective light modulator for generating an image, a light source unit for illuminating the light modulator, and projection optics which include first and second partial optics, the projection optics have an optical axis. Each optical boundary surface of each lens of the first partial optics is curved and/or arranged such that, in a reference plane in which the optical axis of the projection optics is located and which is divided by the optical axis into upper and lower half-planes, each reflection ray bundle exiting the first partial optics proceeds completely either into the first or into the second half-plane. Thus, the invention prevents the reflection ray bundles from being projected onto the projection surface.
According to one embodiment a method for aligning a light source includes providing a lamp and a lamp interface. The lamp interface has an alignment aperture disposed thereon. The method also includes aligning the lamp with respect to the lamp interface until a desired amount of light is focused on the alignment aperture. The method further includes fixing the lamp to the lamp aperture to form an aligned lamp assembly after obtaining a desired lamp alignment. Then the aligned lamp assembly is coupled to an integrating rod.
