Abstract: A polarization rotating optical device is provided. The device comprises a prism configured to accept an input collimated optical beam and redirect the beam by means of total internal reflection at three or more faces of the prism. The first face reflects an incident collimated beam at an angle of 90 degrees with respect to the original beam direction. The incident and reflected beams are comprised of orthogonal s and p polarized components, where the s and p directions are defined with respect to the plane containing the incident and reflected beam directions in the conventional manner. One or more prism faces then reflect the beam within the plane normal to the incident beam. The sum of the included angles of these reflections must total an odd multiple of 90 degrees. The final prism face reflects the beam by 90 degrees in a third plane orthogonal to the planes of the preceding reflection.

Abstract: An epifluorescent microscope (11) is constructed with a quick changing set of filters (13,20,21). A wheel (13) containing a plurality of dichroic beamsplitter mirrors (6165) mounted equidistance from a center axis (66) of the wheel is mounted at a 45° angle within the lightpath and provides a beamsplitter function. Light from an excitation source (12) is provided as monochromatic light, so that light from the excitation source (12) is reflected by a selected one of the dichroic mirrors (6165) to the specimen (15), and Stokes shifted light from the specimen (15) is transmitted through the dichroic mirror (6165). By separately mounting the dichroic mirrors (6165), the dichroic mirrors can be quickly moved and a quicker change of sensed fluorophores is achieved. An additional advantage is that excitation (20) and emission (21) filters can be quickly changed independently of the dichroic mirror element (13).

Abstract: In a projector, the precision of color synthesis is improved and the generation of vertical stripes in the projected image is suppressed by a dichroic prism used for color synthesis that employs at least the following aspects. (1) The dichroic prism is formed using triangular prisms, in which projections or grooves are provided that have two faces parallel to two pasted faces of the triangular prisms, the projections or grooves being integrally injection-molded on faces of the triangular prisms that are substantially perpendicular to the light beam (i.e., the faces through which no light beam passes); (2) the dichroic prism is positioned using marks on the pasted faces of the triangular prisms; or (3) the dichroic prism is formed by engaging triangular prisms in which recesses or projections are formed.

Abstract: The invention provides a light diffuser comprising a macro diffusion efficiency variation wherein at least part of the diffuser is colored. The invention also provides light diffuser comprising a macro diffusion efficiency variation wherein at least part of the diffuser is colored for rear projection displays, back-lighted imaging media, and a liquid crystal display component and device. The invention further provides a process for preparing such a diffuser.

Abstract: Disclosed is a diffuse reflector comprising a macro reflection efficiency variation. The invention provides improved light reflection for a back lit display while simultaneously diffusely reflecting specular light sources.

Abstract: Disclosed is an optical element containing a rough surface having a roughness average equal to at least 5 micrometers wherein the rough surface contains at least two roughness populations in which the roughness average of the at least two populations varies by at least 8 micrometers. The invention provides an optical element containing an integral optical spacer while simultaneously providing scratch and impact resistance.

Abstract: Disclosed is a light diffuser comprising a perimeter area and a central area wherein the perimeter area contains a light director that directs at least a portion of the light incident on it toward the central area.

Abstract: A 4-prism color management device (600) comprised of first, second, third, and fourth prisms (610, 612, 614, 616). The first prism (610) is adjacent to the second prism (612) with an air gap (620) interposed therebetween, the second prism (612) is adjacent to the third prism (614) with an air gap (624) interposed therebetween, and the third (614) prism is adjacent to the fourth prism (616) with an air gap (626) interposed therebetween. The first prism (610) includes a first surface (630) for inputting and outputting a beam of light. The second prism (612) includes a first dichroic surface (642) mounted at a first angle (&bgr;) with respect to the first surface (630) for reflecting light of a first color and for transmitting light of a second color and light of a third color. The third prism (614) includes a second dichroic surface (644) mounted at a second angle (&khgr;) with respect to the first surface (630) for reflecting light of the second color and for transmitting light of the third color.

Abstract: An illumination device is provided of the type arranged at the front which is of low power consumption and of high recognisability both when the illumination is turned on and when illumination is turned off. An illumination device arranged at the front face of an illuminated object has a light-guide plate forming a transparent flat plate shape and formed with point-form optical extraction structures on its surface or in a position facing this surface, and a light source arranged opposite and end face of this light-guide plate. The light source is for example a point light source. The optical extraction structures are for example pillar-shaped projections and these are arranged two-dimensionally. The function is provided that, when this illumination device is arranged at the front of the illuminated body, rays are projected on to the illuminated body and rays reflected by the illuminated body are transmitted with scarcely any dispersion.

Abstract: A high-performance real-image finder optical system reduced in size, particularly in thickness, includes a positive objective optical system, an image-inverting optical system for erecting an intermediate image formed by the objective optical system, and a positive ocular optical system. The objective optical system has at least two movable units moving when zooming is performed. A prism is placed on the object side of the intermediate image. At least one reflecting surface of the prism has a rotationally asymmetric surface configuration. At least one reflecting surface of the image-inverting optical system is formed from a roof surface. The finder optical system satisfies the following condition: 1.0<d/(fW·tan &thgr;W·Z)<2.

Abstract: An optical assembly (11) is formed by individually positioning a plurality of prisms (15) using mechanical reference surfaces (19) which are associated with the prism's diagonal (13) and are preferably formed by extensions of a first sub-prism (17A) beyond a second sub-prism (17B). The mechanical references surfaces and a first side of the prism engage fixed mechanical references (23) associated with a housing. A locking element (21) engages a second side of the prism and forces the mechanical reference surfaces and the first side of the prism against the fixed mechanical references to achieve accurate positioning of the prism's diagonal (13).

Abstract: An optical wedge compensates for a vertically drifting laser beam in response to ambient temperature fluctuations. A slit sensor is formed onto a surface of the wedge to separate a single light pulse from a plurality of light pulses. A reflective filter layer is applied to a side opposite the slit sensor so an incident laser beam is attenuated thereby precluding damage to the slit sensor. The reflective filter coating further filters out unwanted light energy. The wedge is shaped so as to maintain a position of a focal point of a laser beam on the slit sensor and to prevent reflected light from damaging a laser source.

Abstract: An optical film includes a transparent film having provided on one side thereof an adhesive layer, a layer which includes a plurality of groove structures, each structure having optical-path changing slopes oriented substantially toward certain directions at an angle of 35 to 48 degrees relative to the transparent film, and which is laid on the other side of the transparent film, a transparent cover film for covering the surface of the layer in which the groove structures are formed, and at least an anti-reflection layer and an anti-moisture layer laid on an exterior side of the cover film.

Abstract: A light focusing and dispersing apparatus of a light source module is disclosed. The light focusing and dispersing apparatus is particularly used in image scanners such as a single pass color scanner. The light focusing and dispersing apparatus concentrates light from a light source to form a light beam so as to upgrade the use efficiency of light energy. The light focusing and dispersing apparatus disperses the light beam from the light source to form red, green and blue light beams to illuminate a document to be scanned. The red, green and blue light beams reflected from the scanned document emit onto array of image sensors comprising red, green and blue light sensitive regions respectively.

Abstract: The invention provides a numerical aperture limiter for an optical thermal imaging system, comprising at least one pair of wedge-like prisms made of a transparent material having a known index of refraction, the prisms of the pair being disposed in close mutual proximity and in opposite orientation with the narrow end of one prism adjacent to the wide end of the other prism, the prism surfaces facing one another of the pair of prisms being spaced apart from one another by a distance at least equal to the wavelength of the light used by the imaging system, with the vertex angle of each one of the prisms being a function of the desired numerical aperture and the index of refraction.

Abstract: The present invention provides a polarization separation element comprising a first array of prisms having a wedge-shaped cross-section, and a second array of prisms also having a wedge-shaped cross section. One of the prism arrays is an array of birefringent prisms. The present invention also provides a polarization conversion system having a polarization separation element of the above type for directing light having a first polarization in a first direction and for directing light having a second polarization different from the first polarization in a second direction different from the first direction; and one or more polarization conversion elements for converting light having the first and second polarizations to light having a substantially common output polarization. The polarization conversion system of the invention is suitable for use in a projection display system.

Abstract: The invention concerns a microsystem module, in particular for use in microoptical systems, the module consisting of a body on the surface of which at least one functional area and support areas for attachment to adjacent microsystem components are provided. According to the invention, in order to provide a microsystem module of this type which can be connected to adjacent microstructure system components with an extremely good fit and in an exactly reproducible manner and preventing damage to the adjacent components and the sensitive functional areas of the microsystem module, the support areas are disposed in the region of outwardly projecting surface regions of the body which are set back relative to the support areas in the direction towards the interior of the body. The functional areas are disposed with very narrow tolerances in a dimensionally accurate manner relative to the support areas.

Abstract: The invention relates to an image reversion system (500) which enables an image reversion and beam transposition of a plurality of observation beam paths (503a, 503b, 504a and 504b) to be carried out simultaneously. The system includes at least one Porro prism system and is designed in such a way that it can be arranged in a convergent beam path. The inventive system is suitable as an image reversion system in an ancillary module for operational microscopes used in ophthalmoscopy due to the low overall height thereof.

Abstract: A surface light source device includes a light guide plate. A light beam generated from a point light source is irradiated from a corner portion formed at a side surface of the light guide plate. The irradiated light beam is emitted from an upper surface on which prisms are formed. The prisms extend in a circular arc form so as to connect two side surfaces forming the corner portion.

Abstract: A frame is used to form a liquid tight seal between optical components such as beam splitters in a prism assembly suitable for use in a kernel. The frame covers channels and intersections of channels between the optical components. A sealant, such as an adhesive or gasket material is placed between the frame and the optical components to create the seal. Many different configurations of optical components may be held together in an assembly using the frame. In one embodiment, the optical components are pathlength matched beam splitters arranged in pathlength matched positions of a prism assembly suitable for use in a kernel. In one embodiment, the frame includes a central plate and a bottom portion, arms, and one or more interlocking mechanisms to hold the frame around the optical components.

Abstract: Kernels are designed in different configurations based on design properties of an enclosure or other requirements. A prism assembly having various types of filters, waveplates, beam splitters (e.g., path length matched beam splitters) and/or other optical components are provided to selectively direct light beams to each of red, green, and blue microdisplays that manipulate the light and then combine the manipulated lights into an output image. The prism assembly includes an input face, an output face, and other faces on which the microdisplays are attached in a number of different configurations. Requirements and exact placement of optical components varies depending on which microdisplay is attached to which face. The components of the prism assembly may be arranged in path length matched positions.

Abstract: An optical glass for a prism, which has high transmittance, high homogeneity and excellent thermal stability, and an optical part for a prism, which is formed of the optical glass, the optical glass being an optical glass (1) wherein the absolute value of K&Dgr;t represented by the relational expression (I), 1 K ⁢   ⁢ Δ ⁢   ⁢ t = [ ( specific ⁢   ⁢ heat × specific ⁢   ⁢ gravity ) / thermal ⁢   ⁢ conductivity ] × Young ' ⁢ s ⁢   ⁢ modulus × thermal ⁢   ⁢ expansion ⁢   ⁢ coefficient × ( 1 - Poisson ' ⁢ s ⁢   ⁢ ratio ) × photoelastic ⁢   ⁢ constant ( I )

Abstract: The object of the present invention is to provide a real image viewfinder optical system with high optical performance and compactness, whose dimension of a whole optical system including an image inverter optical system is small in the thickness direction, and whose dimension to an object side of an eyepiece lens system is small in the thickness direction. A real image viewfinder optical system comprises, in order from an object side, an objective lens system having a positive refractive power as a whole, an eyepiece lens system for observing a real image formed by the objective lens system and having a positive refractive power, and an image inverter optical system for erecting the image to be observed and arranged to an exit pupil side of a lens located to the most object side of the objective lens system and also to the object side of a lens located to the most exit pupil side of the eyepiece lens system. Conditional expressions are satisfied.

Abstract: The multi-beam scanning device includes first and second light emitting elements that emit first and second light beams, respectively, a polygon mirror that deflects the first and second light beams to simultaneously scan the first and second light beams across an object. A prism having a light entrance portion and a light exit portion is located between the light emitting elements and the polygon mirror such that the first light beam enters the first prism through the light entrance portion and exits from the first prism through the light exit portion toward the polygon mirror. The light exit portion is inserted into the optical path of the second light beam to prevent a part of the second light beam from proceeding toward the polygon mirror.

Abstract: An optical instrument for observation includes, in order from the object side, an objective lens system having positive refractive power, an erecting optical system, and an ocular lens system having positive refractive power. When an anti-vibration mechanism is used to maintain the erecting prism at an orientation in space that is stabilized so as to prevent image degradation due to vibrations of the optical instrument for observation, the erecting prism is constructed to satisfy specified conditions so that ghost light is not generated and so that the optical instrument for observation may be compact.

Abstract: In an optical member, comprising a laminated body in which adhesive layers are prepared in an optical material, wherein a side face of the laminated body has a concavo-convex repeated structure by waveform, rectangle, trapezoid, or zigzagged form, the adhesive layer exposed in a side face may not be easily drawn out by a contact to conveyance instruments or by a friction caused when the optical members are taken out from a piled state etc., and also conveyance interference in assembly line, break of adhesive in adhesive layer side face, a pollution with adhesives, a display interference may not be easily generated.

Abstract: An object of the invention is to provide a sidelight type backlighting apparatus having high brightness, which is yet reduced in uneven brightness, and to provide a reflector substrate having a surface profile necessary for obtaining such apparatus and a reflector having high brightness and long durability in which the reflector substrate is implemented. A buffer against strain is formed by providing space by protrusions or the like between a light guiding plate of a planar light source apparatus and a reflecting surface of a reflection sheet provided on one main surface of the light guiding plate. Further, a base layer, a metallic layer mainly containing silver, and a light transmitting oxide layer are laminated on the substrate in this order to form a reflection layer.

Abstract: Binoculars having a prism assembly between the objective and ocular, wherein the prism assembly is secured on a prism holding device by means of a permanently elastic sealing compound.

Abstract: An optical panel includes a transparent serrated first side, and an opposite second side, and a black material provided on the serrated first side for intermittently blocking or absorbing light transmission. Image light may be transmitted through the panel at the serrations, with contrast provided by the black material.

Abstract: The invention relates to an optical sight for a combat vehicle, intended to be mounted in a weapon turret (26) of the vehicle in order to make possible sight lines at elevations between roughly −10° and 90° of a weapon barrel mounted pivotably about a horizontal axis in the weapon turret. The sight comprises a lower standard sight unit (12), which deflects vertical incident light by 90° to an eyepiece (16), and a top mirror (18), located above the standard sight unit (12) and pivotable in synchronism with elevating movements of the barrel, likewise about a horizontal axis. Positioned above the standard sight unit (12) is a deflection prism (20) which has an upper surface (22) which faces the top mirror, is inclined at roughly 45° to the vertical and is designed to reflect incident light at an angle of roughly 45° to the surface and less, but to transmit light which is incident at roughly 90° to the surface (22).

Abstract: In a vehicle periphery visual confirmation apparatus, between the vertical angle portion 5 of a prism 4 and the front end portion 28 of a case 3A is interposed a light shield portion 3a which shields light rays crossing substantially in the right and left direction in front of the prism 4. Even in case where light rays coming from the outside enter in front of the vertical angle portion 5 of the prism 4 and are going to cross in front of the prism 4, the light rays can be prevented by the light shield portion 3a. This can prevent the overlapped reflection of a vision image resulting from the fact that the light rays crossing in front of the prism are reflected by the internal surfaces of the penetration window portions and enter the interior portion of the prism.

Abstract: The invention relates to a tube for an optical instrument, such as a microscope, having several rotary joints (19, 20, 21) connected serially one behind the other. Each of the rotary joints (19, 20, 21) includes a brake (32, 33, 38) via which the rotary joints are secured against an unintended rotation. The brakes of the rotary joints (19, 20, 21), which are connected serially one behind the other, are simultaneously releasable by actuation of the single operator lever (39). For this purpose, a system of pins (42) and tilt levers (43) is mounted in the tube via which the actuation of the operator element (39) is transmitted to the brakes (32, 33, 38) connected serially one behind the other.

Abstract: An image-erecting viewing optical system includes a first prism having an incident surface and at least two reflection surfaces, a front lens group of an objective optical system, a second prism having an incident surface and at least two reflection surfaces, a-rear lens group of the objective optical system, a field stop, and an eyepiece optical system, in this order from the object. One reflection surface of the first or second prism includes a roof-mirror surface.

Abstract: A wavefront sensor is provided to determine characteristics of an incoming distorted energy beam. The sensor includes a plurality of multi-lens array and a beam detector, such as a CCD camera. The multi-lens array focuses the energy beam to a multiple focal spots forming a diffraction pattern on the CCD camera. The invention teaches a method to eliminate or substantially reduce a cross talk or interference in measuring the intensity of the focal spots. The beam detector or CCD detects the resulted focal spots and determines the characteristics of the incoming energy beam. The method and wavefront sensor according to this invention can be used in combination with an exposure apparatus in a semiconductor wafer manufacturing process.

Abstract: In an optical sheet 10 having a prism surface 16 formed by providing unit prisms 14 on the upper surface of a transparent base material 12, a coating layer 18 is provided on the reverse surface of the transparent base material opposite to the prism surface 16, spherical beads 20 are arranged projecting from the surface of the coating layer 18 by 1 to 10 &mgr;m in height, and the coating layer 18 is brought into contact with the flat and smooth surface 22A of the light-transmissive material 22 through the spherical beads 20 which are put between them. The spherical beads are 1 &mgr;m or less in half bandwidth of the distribution of particle diameters and are made uniform in height projecting from the coating layer 18.

Abstract: The present invention is a light directing construction for use in a display apparatus. The light directing construction includes a light directing film that has a prismatic structure having two sides, where one side includes saw tooth formations having tilted surfaces, and a metal coating on the side of the prismatic substrate having the saw-tooth formations. A corrosion-resistant feature is provided on the light directing construction to minimize the effects of corrosion experienced in salt atmospheres. In a first embodiment of the invention, the light directing construction includes an intermediate layer positioned between the light directing film and the metal coating. In a second embodiment of the invention, a peripheral polymeric coating is provided on the light directing constriction. This peripheral coating can be formed with a laser.

Abstract: The invention relates to a viewing and an image pickup optical system for display devices, which can be used with high efficiency at a plurality of wavelengths and enables bright images to be viewed with satisfactory color reproducibility and well-corrected aberrations. The optical system comprises a first prism 3, a second prism 4 and a volume hologram element 6 disposed between them and cemented to them. The hologram element 6 comprises a first volume hologram optimized in such a way as to effect diffraction at least at a first wavelength and a second hologram optimized in such a way as to effect diffraction at a second wavelength different from the first wavelength. The first and second holograms forming the hologram element 6 are identical with each other in terms of the shape and spacing of interference fringes on their surfaces but different from each other in terms of the spacing and tilt of interference fringes in their hologram media.

Abstract: Devices and methods for applying heat to a platen of a biometric image capturing device are described that remove and prevent the formation of excess moisture on the platen. These devices and methods prevent undesirable interruptions of total internal reflection of a prism that result in biometric images having a halo effect. In embodiments of the invention, an electrically conductive transparent material is used to apply heat to the platen. In other embodiments, resistive heating elements attached to non-optical areas of the platen (e.g., the ends) are used to apply heat to the platen. Heater assemblies according to the invention can be used to heat an area where a biometric object is placed, or an area adjacent to where the biometric object is placed, to remove and prevent the formation of excess moisture on the platen.

Abstract: An optical wedge compensates for a vertically drifting laser beam in response to ambient temperature fluctuations. A slit sensor is formed onto a surface of the wedge to separate a single light pulse from a plurality of light pulses. A reflective filter layer is applied to a side opposite the slit sensor so an incident laser beam is attenuated thereby precluding damage to the slit sensor. The reflective filter coating further filters out unwanted light energy. The wedge is shaped so as to maintain a position of a focal point of a laser beam on the slit sensor and to prevent reflected light from damaging a laser source.

Abstract: The present invention provides an enhanced viewing eyepiece for a micro-display. In one embodiment, the invention is an optical imaging system that includes a prism having a first face directed toward a display to receive light from the display and direct it through a second face, a converging optical element between the second face of the prism and the display, and a reflective converging optical element adjacent the second face of the prism to receive the display light through the second face of the prism and reflect it back into the second face of the prism, the invention further includes a diverging optical element aligned with the reflective converging optical element to receive the display light reflected back into the first prism and direct it to an exit pupil.

Abstract: A beam shaping optical system which is provided with a first wedge prism having two refractive surfaces defining a first principal section, and a second wedge prism having two refractive surfaces defining a second principal section that is parallel to the first principal section, wherein a reference ray of light forms incident angles at each of the refractive surfaces of the prisms satisfying the following condition (1): &LeftBracketingBar; ∑ j = 1 L ⁢ α j &RightBracketingBar; < 0.020 .

Abstract: An endoscope includes an optical train or image-to-video conversion device, defining a longitudinal axis, for receiving an image for transmission to a viewing device. A first prism having a reflective surface at 45° to the longitudinal axis and laterally offset from is mounted for rotation about an axis that is perpendicular to and intersecting the longitudinal axis and the axis intersecting the center of the reflective surface. A second prism with a reflective surface at 45° to and intersecting the longitudinal axis is also provided. The field of view is illuminated by light transmitted to a third prism with a reflective surface mounted symmetrically about the longitudinal axis with respect to the first reflector and rotatable synchronously with the first reflector. In this way, the direction of view and of illumination can an be varied synchronously over a range of about 120°.

Abstract: A prism optimally separating and synthesizing a light beam of a wide angle of incidence. A diffraction prism 15 of the present invention is so constructed that a diffraction grid 21 is sandwiched between a pair of diffraction grid substrates 22, a pair of prism substrates 24 are bonded to the surfaces of the prism substrates 22 facing the diffraction grid 21 with interposition of adhesive layers 23, and a diffraction grid medium 25 having a refractive index substantially equal to that of the prism substrates 24 is charged in a gap defined by the diffraction grid 21 and the prism substrates 24, with the respective component members being optically combined together. An incident light is led to the diffraction grid 21 and separated on transmission or reflection by the operation of diffraction by the diffraction grid 21.

Abstract: A color splitting prism assembly (100) comprised of three prisms. Each a dichroic filter at an interface (112) between a first and second of the three prisms reflects a first primary color component of a white light beam passing through the prism assembly. The first primary color component is directed to a first modulator (118). The remaining portions of the white light beam enter a second prism (108) and strike a second dichroic filter at the interface between (124) the second and third prisms. The second dichroic filter separates a second primary color component from the white light beam leaving a third primary color component to travel through the third prism (110) to a third modulator. The second primary color component of the white light beam is directed to a second modulator (128).

Abstract: In a vehicle periphery visual confirming apparatus 1A, the vertical angle portion 5 of a prism 4 is chamfered by cutting away the vertical angle adjacent areas 5L, 5R, and light rays 18R (18L) entering the portion of the prism 4, where the vertical angle adjacent areas 5R (5L) was once present, are allowed to pass in front of the chamfered surface 5a and go to the outside through the penetration window portion 2L (2R) of a case, or, are allowed to enter the chamfered surface 5a and are scattered by the rough surface of the chamfered surface 5a, so that the light rays are prevented from advancing into the prism 4.

Abstract: An optical sheet to be used for a back light unit of a liquid crystal display having at least a lamp and a light guiding plate has the following structure. The optical sheet is constituted by a lower base portion and an upper fitting portion which are fitted each other in a vertical direction with less margin, and the base portion and the fitting portion are formed of materials having different refractive indices. The base portion is provided with a large number of triangular portions having a triangular sectional shape in parallel, the triangular portion having a first side surface positioned on the left side and a second side surface positioned on the right side. Moreover, the first side surface of the triangular portion has an angle which is equal to or greater than an angle formed between a direction taking a peak of a ray refracted and incident on an inside of the base portion through a light guiding plate and the transverse direction.

Abstract: An integrating rod (100) for combining light beams from two or more sources. A first light beam (104) enters the integrating rod 100 through a first entrance face (102) to a first reflecting face (110). The light is reflected by the first reflecting face (110) and travels along the major axis (114) of the integrating rod (100) to an exit face (116). A second light beam (108) from a second light source enters the integrating rod (100) through a second entrance face (106). The second light beam may be reflected by a second reflecting face (112) and travels along the major axis (114) to the exit face (116). The two light beams experience multiple reflections as they travel along the integrating rod and leave the integrating rod (100) through the exit face (116) as a single homogenous light beam.

Abstract: The invention provides a reflective optical element which has three or more reflecting surfaces by which a light flux from an object is successively reflected. In an area enclosed by each of the reflecting surfaces, the reference axis intersects at least two times and the light flux forms an intermediate image. The reference axis is a path of the light beam which passes through the center of an object surface, is then reflected by the reflecting surfaces, and passes through a center of a pupil.

Abstract: The present invention pertains to an optical device useful in a projection system. The optical device can be designed for easy replacement of selected parts, if necessary, without the need for extensive realignment procedures for the projection system.

Abstract: An optical film for use in transparent displays, such as reflective LCDs. The optical film has three-dimensional, prismatic structures that reflect incoming light. The prismatic structures are configured so that the reflecting facets orient the reflected light in desired reflective light pattern. The pattern shape and intensity can be controlled by the shape and dimensions of the various reflecting facets. In one embodiment, the height of the prismatic structure varies along two dimensions of the structure.