Abstract: An optical device is provided comprising a plurality of prisms, two dichroic surfaces having different wavelength characteristics from each other, and a prism surface that satisfies a total reflection requirement for a predetermined light component. Also provided is a projection display apparatus comprising a light source, light valves for respectively modulating components of the light from the light source, an optical device for chromatically synthesizing the modulated light components, and a projection section for projecting the modulated light. Optionally, the optical device may also be used in the projection display apparatus for separating the light from the light source into the multiple light components. Further provided is an image capturing apparatus comprising a taking lens unit for receiving light, an optical device for separating the light received by the taking lens unit into multiple light components, and imaging devices for respectively converting the multiple light components into image data.

Abstract: A scanning optical system is used to re-form an original image on a CCD line sensor. The optical system has an object side lens unit, a mirror and an image side lens unit. The object side lens unit condenses light from the object. The mirror is arranged between the object side lens to deflect the light having passed through the object side lens unit for scanning. An exit pupil of the object side lens unit coincide with an entrance pupil of the image side lens unit.

Abstract: A scanning optical system is used to re-form an original image on a CCD line sensor. The optical system has an object side lens unit, a mirror and an image side lens unit. The object side lens unit condenses light from the object. The mirror is arranged between the object side lens to deflect the light having passed through the object side lens unit for scanning. An exit pupil of the object side lens unit coincide with an entrance pupil of the image side lens unit.

Abstract: An optical device is provided comprising a plurality of prisms, two dichroic surfaces having different wavelength characteristics from each other, and a prism surface that satisfies a total reflection requirement for a predetermined light component. Also provided is a projection display apparatus comprising a light source, light valves for respectively modulating components of the light from the light source, an optical device for chromatically synthesizing the modulated light components, and a projection section for projecting the modulated light. Optionally, the optical device may also be used in the projection display apparatus for separating the light from the light source into the multiple light components. Further provided is an image capturing apparatus comprising a taking lens unit for receiving light, an optical device for separating the light received by the taking lens unit into multiple light components, and imaging devices for respectively converting the multiple light components into image data.

Abstract: 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 0.2≦&ggr;F≦0.

Abstract: An image projector has an optical integrator for splitting illuminating light into multiple light beams. The light beams are reflected by a reflecting member so as to pass through a first half of an effective light pass-through area of a projection optical system. An image synthesizing unit generates a projection image from the light beams, and the projection image passes through a second half of the effective light pass-through area of the projection optical system, so as to be projected onto a screen.

Abstract: A display apparatus of the present invention includes: an illumination optical system for emitting illumination light; a reflective display panel divided into a plurality of pixels, illuminated by the illumination light from the illumination optical system, and selectively reflecting the incident illumination light pixel by pixel as projection light; a projection optical system for projecting image information the reflective display panel onto a projected surface by transmitting the projection light reflected at the reflective display panel; and a reflection angle converting optical system disposed ahead of the reflective display panel, changing the angle of incidence of the illumination light on the reflective display panel, and adjusting the sum of the angle of incidence of the illumination light on the reflective display panel and the angle of reflection of the projection light at the reflective display panel.

Abstract: A projector optical system has a reflection-type display panel, an illumination optical system for illuminating the reflection-type display panel, and a projection optical system for projecting the images displayed on the reflection-type display panel onto a screen. The projection optical system has, from the screen side, a front lens unit and a rear lens unit. A light-deriving means for directing illumination light toward the reflection-type display panel is disposed between the front and rear lens units. Additionally, the following condition is fulfilled: 0.2<&phgr;F/&phgr;<0.9 where &phgr;F represents the optical power of the front lens unit of the projection optical system, and &phgr; represents the optical power of the entire projection optical system.

Abstract: A scanning optical system is used to re-form an original image on a CCD line sensor. The optical system has an object side lens unit, a mirror and an image side lens unit. The object side lens unit condenses light from the object. The mirror is arranged between the object side lens to deflect the light having passed through the object side lens unit for scanning. An exit pupil of the object side lens unit coincide with an entrance pupil of the image side lens unit.

Abstract: A projector optical system has a reflection-type display panel, an illumination optical system for illuminating the reflection-type display panel, a projection optical system for projecting the images displayed on the reflection-type display panel onto a projected surface, and a light-deriving means for directing illumination light toward the reflection-type display panel. The projection optical system has, from the projected-surface side, a front lens unit and a rear lens unit. The light-deriving means is disposed between the front and rear lens units. Additionally, the following condition is fulfilled:-1.5<.phi.F/.phi.<-0.1where .phi.F represents the optical power of the front lens unit of the projection optical system, and .phi. represents the optical power of the entire projection optical system.

Abstract: A Zoom lens system, from the enlargement side, has the first to fourth lens units having the negative, positive, negative, positive optical power, respectively. The third lens unit has a meniscus lens having a convex surface on the enlargement side. The fourth lens unit has two positive lenses. During zooming from the shortest focal length condition to the longest focal length condition, the second and third lens units move along the optical axis so that a distance between the second and third lens units increases and a distance between the third and fourth lens units decreases. The zoom lens system fulfills the following conditions:0.30<.vertline..PHI.3.vertline..multidot.fs<0.903.ltoreq..vertline.(r.sub.MB +r.sub.MA)/(r.sub.MB -r.sub.MA).vertline.Here, .PHI.3 represents an optical power of the third lens unit; fs reprents a focal length of the entire zoom lens system in the shortest focal length condition; r.sub.MB and r.sub.