Abstract: A signaling device includes a light source and a Fresnel optical system. Constructed in the form of ellipses on its rear side, the Fresnel optical system has defocusing lenses that form elongated focal areas in the focal plane. Despite the use of a light source of small lateral extent, the signaling device has a radiation characteristic with a large aperture angle.

Abstract: A Fresnel lens sheet has an entrance surface provided with a plurality of total-reflection Fresnel lens elements. Each of the total-reflection Fresnel lens elements has a light-receiving facet and a total-reflection facet that deflects part of or all the image light fallen on the light-receiving facet in a desired direction. The Fresnel lens sheet meets a requisite condition expressed by an expression: A1?0.6T1/L1, where L1 (mm) is the horizontal length of the Fresnel lens sheet, T1 (mm) is the thickness of the Fresnel lens sheet, and A1 (%) is maximum elongation percentage of the Fresnel lens sheet at which the Fresnel lens sheet lengthens due to moisture absorption. The Fresnel lens sheet includes a Fresnel lens element sheet, and an auxiliary sheet attached to the exit side of the Fresnel lens element sheet. The Fresnel lens element sheet enables efficient molding-removing work for removing the Fresnel lens element sheet from a mold.

Abstract: An integrated solar concentrator and tracker is constructed from a beam deflector for unpolarized light in combination with a fixed optical condenser. The one-dimensional beam deflector consists of a pair of prism arrays made from a material whose refractive index can be varied by applying an electric field. Two of the one-dimensional concentrators can be arranged with their faces in contact and with their prism arrays perpendicular to construct a two-dimensional beam deflector. The intensity and distribution of an applied field modifies the refractive index of the individual prisms in order to keep direction of the deflected beam fixed as the incident beam shifts. When the beam deflector is used with the fixed concentrator the result is that the position of the focus remains fixed as the source moves.

Abstract: An optical pickup apparatus for reproducing information from an optical information recording medium or for recording information onto an optical information recording medium, is provided with a first light source for emitting first light flux having a first wavelength; a second light source for emitting second light flux having a second wavelength, the first wavelength being different from the second wavelength; a converging optical system having an optical axis and a diffractive portion, and a photo detector; wherein in case that the first light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the first light flux is greater than that of any other ordered diffracted ray of the first light flux, and in case that the second light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the second light flux is greater than that of any other ordered diffracted

Abstract: An optical scanning device for scanning a dual-layer optical record carrier with dual orthogonally polarized radiation beams. The device having a spherical aberration compensation optical subsystem including a switchable liquid crystal cell of birefringent material for altering different optical paths lengths provided by a phase structure of stepped annular zones.

Abstract: The present invention provides a Fresnel lens sheet that can, in production using a mold, be easily released from the mold and that scarcely produces stray light upon use, and others. Each prism 2 on the incident side of a Fresnel lens sheet 1 is formed to have a nearly triangular cross section and has a plane of refraction 3 that refracts projected light S incident on this plane and a plane of total reflection 4 that totally reflects, toward the viewer's side, at least part of the light refracted at the plane of refraction 3. Each prism 2 is made so that a root 5 between a prism 2 and a prism 3 situated next to the prism 2, on the plane of total reflection side of the prism 2 (a root 5 defined by the plane of refraction 3 of one prism 2B and the plane of total reflection 4 of another prism 2A situated next to the prism 2B, on the side of the plane of refraction 3 of the prism 2B) is curved toward the prism 2A side from the prism 2B side.

Abstract: The invention provides a transmissive screen that can be manufactured at a low cost and show uniform diffusion and moire-free images over the entire screen, and provides a rear projector provided with such a superior transmissive screen. A transmissive screen can include a Fresnel lens portion having Fresnel-lens components on its light-exiting face and a lens array facing the light-exiting face of the Fresnel lens portion and having many lenses on its light-incident face. The transmissive screen can further include separating device for separating the Fresnel lens portion from the lens array portion at least in the periphery of the screen. Such a superior transmissive screen can be included in a rear projector.

Abstract: A method for forming a diffractive lens includes forming an etch stop layer on a first surface of a silicon substrate, forming a diffractive optical element above the etch stop layer, forming a planarization layer covering the diffractive optical element, planarizing the planarization layer, forming a bonding layer on the planarization layer, bonding a transparent substrate on the bonding layer, and etching a second surface of the silicon substrate to the etch stop layer to remove a portion of the silicon substrate opposite the diffractive optical element, wherein the remaining portion of the silicon substrate forms a bonding ring.

Abstract: A Fresnel lens sheet comprises a Fresnel lens on one surface thereof, wherein respective unit surfaces constructing the Fresnel lens sheet have rough surfaces. Since it has a rough surface, it enables suppressing the occurrence of moire, when making up a screen. The other Fresnel lens sheet comprises a Fresnel lens on one surface thereof, and a fly-eye lens or prisms as a regular concavities and convexities configuration for suppressing regular reflection on the surface thereof on a side opposite to the side having the Fresnel lens formed thereon. Since it has on its rear surface a fly-eye lens or a prism, it enables suppressing the occurrence of ghost image.

Abstract: A vehicle window includes a first window side and a second window side. The first window side includes an optical center and a plurality of grooves positioned about the optical center. The grooves have a number of dimensions including a depth and a width. The grooves define surfaces effective to redirect light that passes through said window. At least one dimension of the grooves is varied about the optical center. The window is effective to provide a plurality of angles of light redirection about the optical center.

Abstract: A scanning apparatus includes a radiation source for emitting a light beam, a rotatable prism for deflecting the light beam, and a lens arrangement for projecting the light beam onto a scene to be scanned. The path length that is traversed by the light beam from the radiation source to the lens arrangement is dependent on the angular position of the prism. To avoid a defocussing, the light beam is collimated so that it penetrates through the lens arrangement in a lens section that is dependent on the angular position of the prism, and the lens arrangement has different focal lengths for various lens sections. The focal lengths of the lens sections are thereby selected so that the radiation source respectively lies in the focal point of the lens section that is penetrated by the light beam. A preferred application is for optical spacing distance radar for motor vehicles.

Abstract: A liquid-crystal lens includes a hologram liquid-crystal element having a liquid crystal which provides a light beam transmitting therethrough with a phase change so as to have a wavefront of a blaze-hologram shape; and a segment liquid-crystal element including a first electrode divided correspondingly to the blaze-hologram shape, a second electrode opposed to the first electrode and a liquid crystal for providing the transmitting light beam with a phase change by voltage application to the first and second electrodes, the segment liquid-crystal element being arranged coaxial to the hologram liquid-crystal element.

Abstract: An assembled optical component has a support structure with a reference surface at which a number of individual optical elements are bonded at predetermined positions. The curvature of the reference surface is selected such that optical surfaces of the optical elements are in a predetermined orientation at their assembly positions. The optical elements are preferably planar mirrors simultaneously fabricated from a wafer. An adhesive film attached to the wafer prior to separation of the optical elements assists in temporarily positioning the elements on a temporary fixture, which holds the elements in position, while they are bonded to the support structure.

Abstract: Blends of oligomeric urethane multi(meth)acrylate; optionally at least one other monomer selected from the group consisting of acrylic monomers, styrenic monomers and ethylenically unsaturated nitrogen heterocycles, preferably a polyol multi(meth)acrylate; and nanoparticles of an ethylenically unsaturated, preferably (meth)acrylic-functionalized, titanium or zirconium compound can be cured by ultraviolet radiation in contact with a photoinitiator to produce optical resinous articles having high refractive indices, haze ratings of at most 5% and other properties which may be tailored according to the desired use.

Abstract: An objective lens is provided in an optical pickup device for carrying out the reproduction/record for a plurality of optical information storing media in which the protect substrates of the mediums have a different thickness. The optical functional surface of the optical lens is divided into the central region including the optical axis and the peripheral region arranged outside the central region. The diffractive structure is provided on the peripheral region. When the reproduction and/or the record is carried out for the first optical information storing medium, the diffracted light is condensed on the focal point. When the reproduction and/or the record is carried out for the second optical information storing medium, among flare lights in which diffracted lights having various diffraction orders and passing through the peripheral region are mixed, the light amount of the k-th order diffracted light can be suppressed more than the (k?1)-th order diffracted light.

Abstract: A Fresnel lens for a display device is provided. The Fresnel lens includes a first sloped surface angled to receive input light, a second sloped surface facing the first sloped surface, and a valley floor linking the first sloped surface to the second sloped surface. The valley floor may be configured to scatter stray light reflected from the first sloped surface.

Abstract: A Fresnel lens comprising a substantially polygonal focusing portion adapted to focus solar radiation to a area having the same geometry as the focusing portion of the lens. Also a solar module comprising the Fresnel collecting lens and a substantially polygonal photovoltaic cell. The photovoltaic cell is mounted at distance from the Fresnel collecting lens so that the size of the area substantially matches the size of the photovoltaic cell. Also a solar panel having multiple modules within a glazed building envelope system. The solar panel also includes an actuating mechanism within the glazed window envelope system. The actuating mechanism is operatively connected to the plurality of solar modules and is adapted to move the solar modules to track the sun.

Abstract: A light flux modulated by a picture is shot out from a liquid crystal projector, and projected on the rear surface of the transparent screen, and a user enjoys the picture from the front side thereof. The sawlike prismatic surface is formed on the rear surface of the transparent screen. Edges of the sawlike prismatic surface form concentric circles centering around a point which is given as an intersection of an optical axis of the projector and a downward extensions of the transparent screen. A face looking downward transmits the light flux incident thereon into the transparent screen efficiently on condition that an angle formed by the incident ray of light and the optical axis of the projector is greater than 40° and less than 90°. A face looking upward totally reflects the ray of light incident thereon to the light-shooting surface, if the aforementioned condition is satisfied.

Abstract: Visual display systems that can accommodate off-angle viewing. In one embodiment, a visual display system includes a visual display device, such as a video display device, having a display screen configured to display visual images. The display screen can at least generally face a first direction that is angled relative to a viewing direction. The visual display system can further include an optical tilting device at least generally overlaying the display screen. The optical tilting device can include a refracting lens, such as a Fresnel lens or other device, configured to optically tilt the displayed images toward the viewing direction to facilitate viewing of the displayed images. In another embodiment, the visual display device can be carried by a seatback portion of a passenger seat.

Abstract: A Fresnel lens sheet comprising a Fresnel lens substrate and a Fresnel lens, whose surface of the light source side has an average pitch of 200 &mgr;m or smaller and ten point roughness of 3 to 15 &mgr;m, a rear projection screen obtained by assembling the Fresnel lens sheet and a lenticular lens sheet, and a process for producing these. With the use of the Fresnel lens sheet and the rear projection screen in accordance with the present invention, a labyrinth light inside the screen and a surface reflection are diffused effectively and a ghost caused by them is remarkably reduced. Accordingly, the rear projection television employing the Fresnel lens sheet and the rear projection screen of the present invention provides excellent images without ghost light.

Abstract: A radiation curable resin composition for a Fresnel lens is provided, which exhibits a high elastic modulus and a high refractive index and is superior in adhesion to the plastic substrate and is superior in transparency. A lens layer exhibits excellent shape retention over a wide temperature range and is less likely to chip and crack due to an external force. A Fresnel lens sheet using the radiation curable resin composition is also provided. The resin composition comprises, as an essential component, an epoxy (meth)acrylate (a) having an epoxy equivalent per weight of 450 g/eq or more, which has a cyclic structure and two or more (meth)acryloyl groups; a specific trifunctional (meth)acrylate (b); a (meth)acrylate (c) having a molecular weight of 700 or less from an aliphatic polyhydric alcohol having an oxypropylene structure; and a monofunctional (meth)acrylate (d) having a cyclic structure.

Abstract: Method and apparatus for collimating light of projected images establishes limited few designs of Fresnel lenses to accommodate conventional image projection system having a wide range of sizes of viewing screens for the projected images. A multi-layer image-enhancing filter is disposed to receive substantially collimated image light exiting the Fresnel lens. A light-transmissive structure includes a substrate layer supporting a single layer of contiguously-arranged beads of light transmissive material disposed on an incident surface of the substrate layer. A Fresnel lens includes angularly-pitched segments on one surface and an array of a plurality of elongated lenses aligned in one direction on an opposite surface of the Fresnel lens for passing a projected light image therethough to the layer of beads on the substrate layer.

Abstract: Disclosed is an objective lens of an optical pick-up that converges light beams of two different wavelengths onto recording layers of optical discs of two different standards, respectively. The objective lens includes a refractive lens having a positive power and a diffractive lens structure formed on one surface of the refractive lens. The diffractive lens structure has a plurality of concentric ring areas with minute steps at the boundaries therebetween. The diffractive lens structure maximizes the diffraction efficiency of the third order diffracted light at the shorter wavelength and maximizes the diffraction efficiency of the second order diffracted light at the longer wavelength. This enables the diffractive lens structure to correct the chromatic aberration at the respective wavelengths with keeping high diffraction efficiency.

Abstract: A method for working a die for use with a Fresnel lens, the method being intended to work in an original die plate having a Fresnel molding groove with wall surfaces corresponding to a lens surface and a non-lens surface of the Fresnel lens. A cutting tool having one piece of edge line continuing to a blade end is constructed as a cutting edge. The blade end has formed therein a notched portion which connects the one piece of edge line and another piece of edge line. Thereby, while a relative rotating movement around a center line of the die is made between the cutting tool and the original die plate, the cutting tool is fed into the original die plate with the cutting edge being used as the leading blade.

Abstract: Provided is a resin composition for lens sheet, a lens sheet, and a projection screen which by defining the mechanical properties based on the consideration of the pressure and time factor actually applied to an ionizing radiation curable resin enables obtaining excellent images without, even if any pressure has been applied to the lens sheet surface, causing crush of the configuration of the lens.

Abstract: A Fresnel lens sheet has an entrance surface provided with a plurality of total-reflection Fresnel lens elements. Each of the total-reflection Fresnel lens elements has a light-receiving facet and a total-reflection facet that deflects part of or all the image light fallen on the light-receiving facet in a desired direction. The Fresnel lens sheet meets a requisite condition expressed by an expression: A1≦0.6T1/L1, where L1 (mm) is the horizontal length of the Fresnel lens sheet, T1 (mm) is the thickness of the Fresnel lens sheet, and A1 (%) is maximum elongation percentage of the Fresnel lens sheet at which the Fresnel lens sheet lengthens due to moisture absorption. The Fresnel lens sheet includes a Fresnel lens element sheet, and an auxiliary sheet attached to the exit side of the Fresnel lens element sheet. The Fresnel lens element sheet enables efficient molding-removing work for removing the Fresnel lens element sheet from a mold.

Abstract: The present invention provides a Fresnel lens sheet that can, in production using a mold, be easily released from the mold and that scarcely produces stray light upon use, and others. Each prism 2 on the incident side of a Fresnel lens sheet 1 is formed to have a nearly triangular cross section and has a plane of refraction 3 that refracts projected light S incident on this plane and a plane of total reflection 4 that totally reflects, toward the viewer's side, at least part of the light refracted at the plane of refraction 3. Each prism 2 is made so that a root 5 between a prism 2 and a prism 3 situated next to the prism 2, on the plane of total reflection side of the prism 2 (a root 5 defined by the plane of refraction 3 of one prism 2B and the plane of total reflection 4 of another prism 2A situated next to the prism 2B, on the side of the plane of refraction 3 of the prism 2B) is curved toward the prism 2A side from the prism 2B side.

Abstract: An optical component including: a substrate made from heat absorptive glass having a front surface and a rear surface, at least one of said surfaces being a crenulate surface having optical power.

Abstract: An optical element has diffractive grooves. Each diffractive groove includes a first surface approximated by a predetermined optical function; a second surface extending in a direction to cross the first surface and being parallel to the optical axis; and a third surface to connect the first surface and the second surface. A width of the third surface in the direction perpendicular to the optical axis is 0.5% to 15% of the sum of a width of the first surface in the direction perpendicular to the optical axis and the width of the third surface in the direction perpendicular to the optical axis.

Abstract: An infrared imaging device is provided which comprises first and second plastic Fresnel lenses that are in optical communication with each other. Each of the first and second lenses have a first major surface which is convex and a second major surface which comprises a Fresnel surface. The first lens is adapted to mimic a meniscus asphere correct for conjugates of infinity and for the focal length of said first lens, and the second lens is adapted to mimic a meniscus asphere and is further adapted to act as a field flattener.

Abstract: Provided is a resin composition for lens sheet, a lens sheet, and a projection screen which by defining the mechanical properties based on the consideration of the pressure and time factor actually applied to an ionizing radiation curable resin enables obtaining excellent images without, even if any pressure has been applied to the lens sheet surface, causing crush of the configuration of the lens.

Abstract: An optical or lens system for use with an imaging system of a vehicle includes a plurality of optical elements. The optical elements include less than five optical elements and, preferably, include four optical elements. Each of the optical elements is formed of a plastic material. At least two of the optical elements include a diffractive element. Preferably, a diffractive element is formed on an outer surface of two of the optical elements. The optical system provides and focuses a field of view of a targeted area of at least approximately 100 degrees to an imaging plane. The imaging plane is at an imaging sensor or camera or other imaging device operable to receive the image from the optical system. The optical system further includes an aperture stop between two of the optical elements.

Abstract: An information display system having an output display for presenting information. Optical means are provided that deflect an illumination beam path into the field of view of the observer. Further, a subdividable output display is created that makes it possible to partly obtain information in a vehicle via a head-up display and partly via a traditional or back-projection display. Given seats arranged in rows, for example in airplanes or buses, back rests of preceding seats contain an output display and a communication interface to the seat of the viewer.

Abstract: A planar lens capable of compensating for chromatic aberration and which is easy to manufacture and enables easy assembling of optical pickups and a method for fabricating the planar lens are provided. The planar lens includes a transparent substrate with a lens cavity in a surface of the transparent substrate, and a lens element formed in the lens cavity with a first refracting surface in contact with the bottom of the lens cavity and a second diffracting surface having a diffraction grating opposite to the first refracting surface.

Abstract: An optical element has diffractive grooves. Each diffractive groove includes a first surface approximated by a predetermined optical function; a second surface extending in a direction to cross the first surface and being parallel to the optical axis; and a third surface to connect the first surface and the second surface. A width of the third surface in the direction perpendicular to the optical axis is 0.5% to 15% of the sum of a width of the first surface in the direction perpendicular to the optical axis and the width of the third surface in the direction perpendicular to the optical axis.

Abstract: High spatial frequency optical noise in the form of intensity contrasting picture elements in the display of a projected light image on a bead-oriented image-enhancing filter is significantly reduced by interposing light-scattering material in the optical path between a source of the projected light image and the display in order to inhibit formation and interference of coherent light waves, and to mask the appearance of separate or discrete beaded apertures.

Abstract: A lithography apparatus having achromatic Fresnel objective (AFO) that combines a Fresnel zone plate and a refractive Fresnel lens. The zone plate provides high resolution for imaging and focusing, while the refractive lens takes advantage of the refraction index change properties of appropriate elements near absorption edges to recombine the electromagnetic radiation of different energies dispersed by the zone plate. This compound lens effectively solves the high chromatic aberration problem of zone plates. The lithography apparatus allows the use of short wavelength radiation in the 1-15 nm spectral range to print high resolution features as small as 20 nm.

Abstract: Provided in the present invention are an image pickup lens and a design method thereof which can achieve miniaturization of the system and capable of remarkably improving the optical characteristic with a simple structure. By forming a second face on the image pickup surface side of a lens body into a Fresnel face and unifying a diffraction element with at least a first face on the object face side or the second face on the image pickup surface side of the lens body, it becomes possible to correct the Petzval sum and reduce the curvature of the field so that an excellent image plane can be obtained. Also, due to the color dispersion characteristic of the diffraction element, chromatic aberration can be well corrected. Thereby, the optical characteristic of the image pickup lens can be remarkably improved.

Abstract: An optical device such as an overlay panel for a LCD display, comprises an element of light-transmitting material having a surface configured to form a stepped Fresnel prismatic structure. The light-transmitting material itself or ribbed light refracting element, said element incorporates an array of graded refractive index features adapted to impart light dispersing of diffusing characteristics to the light-transmitting material. In an alternative arrangement, the element of light-transmitting material has a layer configured to form a stepped Fresnel-type surface and an additional layer incorporating such an array of graded refractive index features.

Abstract: To provide a transmissive screen that can be manufactured at a low cost and show uniform diffusion and moire-free images over the entire screen, and to provide a rear projector provided with such a superior transmissive screen. A transmissive screen includes a Fresnel lens portion having Fresnel-lens components on its light-exiting face and a lens array facing the light-exiting face of the Fresnel lens portion and having many lenses on its light-incident face. The transmissive screen further includes separating means for separating the Fresnel lens portion from the lens array portion at least in the periphery of the screen. A rear projector includes such a superior transmissive screen.

Abstract: In an image pickup lens including a lens body, at least one of faces of the lens body is formed into an aspherical shape, and at least one of a first face of the lens body adjacent an object and a second face of said lens body adjacent an image pickup surface is a Fresnel face. Thus, the image pickup lens can be reduced in size, and the optical characteristics of the image pickup lens can be enhanced remarkably in a simple structure.

Abstract: Method and apparatus for collimating light of projected images establishes limited few designs of Fresnel lenses to accommodate conventional image projection systems having a wide range of sizes of viewing screens for the projected images. A multi-layer image-enhancing filter is disposed to receive substantially collimated image light exiting the Fresnel lens. A light-transmissive structure includes a substrate layer supporting a single layer of contiguously-arranged beads of light transmissive material disposed on an incident surface of the substrate layer. A Fresnel lens includes angularly-pitched segments on one surface and an array of a plurality of elongated lenses aligned in one direction on an opposite surface of the Fresnel lens for passing a projected light image therethrough to the layer of beads on the substrate layer.

Abstract: A lens adapted for securement to a holder, for transmission of light, comprising a lens body, defining an axis, threading on the lens body extending about said axis, for reception in threading associated with the holder.

Abstract: In order to provide a noise-free reliable projection type display apparatus which has no movable portion and can display a high quality full-color image, the following arrangement is proposed. In a projection type display apparatus which has an optical modulation device for displaying an image by controlling the reflected state of light, an illumination unit for irradiating the optical modulation device with light, and a projecting optical system for projecting reflected light components of the light components with which the optical modulation device is irradiated, and projects and displays an image formed by the optical modulation device, as the optical modulation device, a mirror array device for modulating light by controlling the tilt amounts of mirrors that form pixels is used.

Abstract: The present invention is a screen, such as is used in back-lit projection screens, having a Fresnel lens laminated to another layer for support. The screen includes a Fresnel lens having an output surface, and a dispersing screen supportingly attached on a first side to the output surface of the Fresnel lens.

Abstract: A Fresnel lens sheet of the present invention is applicable to a transmission-type projection screen, which comprises a layered structure provided with at least a base material layer, a lens layer formed into a Fresnel lens configuration, an incident surface on which projection light is incident and an light-emission surface from which the projection light is emitted, wherein a total reflection surface is disposed in the layered structure at a position between the incident surface and the light-emission surface, the total reflection surface totally reflecting a portion of projection light proceeding on an optical path in a direction from the lens layer side toward the base material layer side.

Abstract: Method and apparatus for collimating light of projected images establishes limited few designs of Fresnel lenses to accommodate conventional projection systems having a wide range of sizes of viewing screens for the ted images. A multi-layer image-enhancing filter is disposed to receive Substantially collimated image light exiting the Fresnel lens.

Abstract: A multidirectional single surface optically shaped film is disclosed. The optically shaped film may include a film having only one surface structure with two or more different, overlapping Fresnel patterns formed in the structured surface for use as thin, decorative film.

Abstract: Method and apparatus for collimating light of projected images establishes limited few designs of Fresnel lenses to accommodate conventional image projection systems having a wide range of sizes of viewing screens for the projected images. A multi-layer image-enhancing filter is disposed to receive substantially collimated image light exiting the Fresnel lens.

Abstract: A non-planar Fresnel reflector array mold pattern and fabrication method are described which can be utilized to manufacture integral non-planar Fresnel reflector arrays which are not subject to molding inclusions. The Fresnel reflector segments comprising the mold pattern are joined at angles to one another and incorporate off-axis Fresnel segments at segment positions in which the optical axis of the segment is not sufficiently parallel to the intended pull direction of the associated mold. The focal point of each off-axis segment lies along a path that is angularly offset from the optical axis of said segment. The use of properly oriented off-axis Fresnel segments within the non-planar Fresnel array result in the elimination of molding inclusions. The mold pattern thus created may be positive or negative, and provides the three-dimensional pattern from which the final manufacturing molds or tools are created.