摘要:
A display apparatus comprises a projecting device for projecting an image, with the projecting device having a projection optical system having a limited pupil diameter and screen device arranged at a position where an image is substantially projected by the projecting device. The screen device has at least two sheets in each of which a number of prisms extending like a straight line or a curve are formed on the surface on the side opposite to the projecting device. Each of the prisms has an effective portion for allowing a light flux from the projecting device to be emitted in a predetermined direction and a non-effective portion which does not contribute to the emission of the light flux in the predetermined direction, and wherein the non-effective portions of another one or a plurality of the other sheets among the plurality of sheets excluding the sheet arranged at the nearest position on the projecting device side are formed so as to have an almost intermediate angle between the angle of a principal ray when a light flux from the projecting device progresses in the sheets and the emission angle of the principal ray when it is emitted from effective surfaces of the prisms of the sheets.
摘要:
A liquid crystal type video projector is disclosed which has a reflection type optical modulator for effective use of beams from a radiation source such as a lamp or the like. The projector further comprises means for modulating the plane of polarization of a polarized beam entering the radiation source and for reflecting the polarized beam, thereby causing a reflection beam and an optical arrangement. The optical arrangement includes a first polarizing beam splitter for separating the beam from the radiation source into P and S polarized components and for directing the S polarized component to the modulator and a converter for rotating the plane of polarization of the P polarized component and converting into another S polarized component for enhanced efficiency of beam utilization. It further includes a second polarizing beam splitter for reflecting the other S polarized component and directing the other S polarized component and directing to the modulator. The polarizing beam splitters are caused to act as an analyzer for colored reflected beams via a dichroic mirror system.
摘要:
A back projection type screen having a screen portion to be disposed at a position whereat an image projected from image projector means is formed, the screen portion being formed by at least one transparent sheet, the screen portion having a vertical direction and a horizontal direction in parallel to the surface of the transparent sheet, and a light diffusing portion formed on the light beam incidence side surface of the transparent sheet which is next to the light beam incidence side of the screen portion, the light diffusing portion transmitting an incident light therethrough and also diffusing reflected light in the vertical direction and the horizontal direction. The specification also discloses an image display apparatus using such screen.
摘要:
A method for mass-producing eccentric Fresnel lens sheets comprising the steps of: preparing a number of concentric Fresnel lens sheets; dividing the concentric Fresnel lens sheets into a first set and a second set each including a plurality of Fresnel lens sheets; cutting out a plurality of first sheets each corresponding to one portion of the eccentric Fresnel lens sheet from each of the Fresnel lens sheets of the first set; cutting out a plurality of second sheets each corresponding to the other portion of the eccentric Fresnel lens sheet from each of the Fresnel lens sheets of the second set; and bonding each of the first sheets and each of the second sheets in such a manner that patterns on the first sheet and the second sheet are continuous to prepare a plurality of eccentric Fresnel lens sheet. The second set can include a third set and a fourth set and a plurality of third sheets are cut out from the third set and a plurality of fourth sheets are cut out from the fourth set. The third sheets and fourth sheets are bonded to the first sheets. The first sheets are relatively large rectangular sheets and the second sheets are small rectangular sheets.
摘要:
An eccentric Fresnel lens is formed from a concentric Fresnel lens sheet or Fresnel lens sheet mold. The concentric Fresnel lens sheet or mold is cut to produce an eccentric Fresnel lens having a center offset from the optical axis of the concentric Fresnel lens.
摘要:
A screen is disposed in the position at which an image is formed by an image projector. The screen comprises a transparent sheet having a longitudinal direction and a latitudinal direction, and a fresnel lens surface formed on one surface of the transparent sheet to condense a light beam entered thereinto and emit the condensed light beam, the focal length of the Fresnel lens surface in the longitudinal direction of said transparent sheet being shorter than that in the latitudinal direction of the sheet.
摘要:
An image display apparatus comprises an image projection system having a projecting optical system, and a screen for displaying an image by receiving the image light deflected by a mirror system. The screen has a plurality of sheets one of which contains a group of cylindrical lenses which act as light transmitting areas and light blocking areas arranged on an image light exit plane along the direction of arrangement of the cylindrical lenses. The screen arrangement is capable of blocking undesirable reflected light.
摘要:
A reflection type liquid crystal light valve comprises a first transparent substrate, a second transparent substrate for supporting the liquid crystal layer together with the first transparent substrate therebetween, a driver for driving liquid crystal molecules of the liquid crystal layer to modulate a light directed to the liquid crystal layer through the first transparent substrate, and a heat sink substrate attached to the second transparent substrate and having a reflection plane for reflecting the light directed thereto through the second transparent substrate to the first transparent substrate, on a plane thereof facing the second transparent substrate.
摘要:
A liquid crystal device is constituted by disposing a display layer between a pair of electrode plates. The display layer comprises a mesomorphic polymer and a low-molecular weight mesomorphic compound. The mesomorphic polymer may preferably be a main chain-type ferroelectric mesomorphic polymer having an ester linkage or a mesomorphic polymer derived from a polymerizable mesomorphic compound. The display layer may preferably comprise a ferroelectric mesomorphic polymer having a dielectric anisotropy .DELTA..epsilon. of -3.0 or below and a low-molecular weight mesomorphic compound incompatible with the mesomorphic polymer and having a positive dielectric anisotropy.
摘要:
This specification discloses a polarization converting apparatus having means emitting non-polarized light, and polarizing means having a light incidence surface and a light emergence surface, the polarizing means receiving the non-polarized light by the light incidence surface and causing polarized light to emerge from the light emergence surface, the size and shape of the light incidence surface being similar to the size and cross-sectional shape of the non-polarized light. The specification also discloses an optical instrument having such apparatus.