Abstract: The present invention is directed to a display device which comprises two layers of insulating substrate, at least the substrate on the viewing side is transparent, an array of display cells sandwiched between the two layers of substrate, a writing means, and optionally an erasing means to magnetically or electrically erase the image. The display cells are filled with a dispersion of magnetic particles which may be charged or non-charged. The display of the invention eliminates the use of the transparent conductor film, such as ITO, on the viewing side. Therefore, the displays of this invention are more cost effective, more flexible and durable and capable of higher image contrast ratio and higher reflectance in the Dmin area.

Abstract: A zoom lens with high optical specification performances and an incorporated electronic imaging system that is much slimmer in its depth direction, albeit having that zoom lens mounted thereon includes a lens group G1 located nearest to the object side, having a reflecting surface M for bending an optical path. The zoom lens satisfies two conditions with respect to a length d as measured along the optical path from the apex of the surface nearest to the object side in lens group G1 to reflecting surface M and a dimension a of the outside shape of a positive lens, found first as viewed along the optical path from the reflecting surface M toward an image side of the zoom lens, in a direction parallel with an optical axis on an object side of the zoom lens with respect to the position where the optical path is bent, respectively.

Abstract: A photonic crystal having a structure of which the refractive index changes with a periodicity defined in a polar coordinate system is disclosed. And an optical waveguide element comprising said photonic crystal, optical inlet and outlet regions on the surface of said photonic crystal, and a defect region of incomplete photonic crystal periodicity formed within said photonic crystal is disclosed. The defect region functions as an optical waveguide path by guiding from the inlet region to the outlet region an optical signal incapable of propagating through the photonic band gap of the photonic crystal.

Abstract: A zoom lens in which when the magnification is changed in the range from a wide-angle position to a telephoto position in infinite object point focusing, spacing between a first lens unit, with negative refractive power as a whole, having a negative lens and a positive lens, and a second lens unit, with positive refractive power as whole, having a positive lens and a cemented lens component constructed with a positive lens and a negative lens, is narrowed and spacing between the second lens unit and a third lens unit, a single positive lens component, is widened, and the zoom lens satisfies the following condition: 2.1<|?2T|<2.8 where ?2T is the magnification of the whole of the second lens unit at the telephoto position in the infinite object point focusing.

Abstract: An image pickup apparatus includes a multifocal optical system in which first and second focal lengths on short and long focal length sides is optically selected; an image pickup device for converting an optical image into an image signal; an image processor which processes the image signal to form an original image; a trimming device for trimming the original image formed by the image processor; a drive controller for switching the optical focal length when the set angle-of-view of the trimming device changes between the second angle-of-view and a third angle-of-view which is smaller than the second angle-of-view; and a memory for storing an original image formed by the image processor at a focal length before the optical focal length is switched by the drive controller. The trimming device forms trimmed images of set angle-of-views while the optical focal length is switched.

Abstract: A thin imaging apparatus with an extremely low profile captures high quality images with outstanding resolution. The imaging apparatus has a light guide, incidence mirror, imaging device, and aperture unit. The incidence mirror reflects and guides light from a subject into the light guide, and the imaging device receives the light from the subject reflected by the incidence mirror and passing through the light guide.

Abstract: The object of the present invention is to provide an eyepiece lens having a large pupil diameter of 10 mm or more, securing higher magnification, equipped with a high quality diopter adjustment function at low cost. The eyepiece lens includes, in order from an eye point side EP, a negative meniscus lens L1 having a concave surface facing to the eye point side EP, a double convex lens L2, and a negative lens L3. Diopter of the eyepiece lens is adjusted by moving the double convex lens L2 along an optical axis. At least one surface of the double convex lens L2 has an aspherical surface having positive refractive power getting weaker in accordance with increase in a distance to the surface from the optical axis, and given conditional expressions are satisfied.

Abstract: A lens barrel has its collapsed length that can be further decreased by removing unnecessary space and bringing lens groups close to each other and a photographic apparatus incorporates the lens barrel. When the lens barrel is collapsed, at least a fourth lens group is retracted from a photographic optical axis by an advance/retract mechanism. In that case, a first lens group and third lens group are aligned along the optical axis and stuffed into the lens barrel, the fourth lens group is placed on the top, bottom, right, or left side of these lenses, and a second lens group is placed on the top, bottom, right, or left side of the first and third lens groups. This reduces the length of the lens barrel. During extension, the second and fourth lens groups are advanced onto the photographic optical axis by the advance/retract mechanism to extend the lens barrel greatly.

Abstract: A lens drive mechanism includes a rotatable lead screw driven to rotate about an axis thereof, the axis extending parallel to an optical axis of a lens group; a non-rotatable guide shaft which extends parallel to the rotatable lead screw; a nut member made of synthetic resin which includes a screw engaging portion, with which the rotatable lead screw is screw-engaged, and a rotation-prevention portion, which is engaged with the non-rotatable guide shaft to prevent the nut member from rotating about the rotatable lead screw; and a lens support frame which supports the lens group and is movable together with the nut member in an optical axis direction. The rotation-prevention portion of the nut member includes a pair of holding portions which are formed integral with the nut member so as to resiliently contact the non-rotatable guide shaft.

Abstract: An illumination optical system having a more simplified structure forms various quadrupole-shaped secondary light sources with two-time rotational symmetry with respect to an optical axis. The apparatus can provide illumination conditions that differ in two perpendicular directions on a radiation-receiving plane. In order to form a secondary light source with a quadrupole-shaped light intensity distribution on an illumination pupil plane, a diffractive optical device is provided in which an entrance light beam is converted into four light beams, and a light beam having a shape of four points centered about the optical axis is formed in a far field. The diffractive optical device is provided with a first diffractive optical member that is rotatable about a first axis parallel to the optical axis, and a second diffractive optical member that is rotatable about a second axis parallel to the optical axis, and that is arranged adjacent to the first diffractive optical member.

Abstract: A mirror assembly including an active lens and a reflective surface. The mirror assembly may change its refractive index when a voltage is applied to the active lens, thereby changing the field of view in the lens. Exemplary applications include a blind spot system in a motor vehicle, in which, upon sensing another vehicle in a driver's blind spot, the mirror assembly changes the driver's field of view to include the blind spot. Additional applications include a magnifying mirror for shaving or applying cosmetics.

Abstract: A lens barrel with a lock arranged to avoid loosening the lock and defocusing the lens barrel when vibrated during focusing and zooming. The lens barrel includes a fixed cylinder, an adjustment ring, lock screws and a lock ring, lock screws and a lock ring. The adjustment ring is slidably attached to the fixed cylinder so as to rectify locations of optical components along the optical axis. The lock screws in screw holes extend at one end of the fixed cylinder in parallel with the optical axis, and each lock screw has a part that serves as a turning force transmitting segment and moves along the optical axis at the end of the fixed cylinder. The lock ring is slidably attached to the end of the fixed cylinder and has an inner surface that is mated with the force transmitting segment to let the lock screws rotate to secure the adjustment ring to the fixed barrel.

Abstract: The invention is directed to a spatial light modulator device that can improve holographic data recording systems, and various methods and systems incorporating the device. The spatial light modulator device includes a diffusive element to diffuse or scatter a data encoded object beam. For example, the diffusive element may comprise a two-layer diffusive laminate formed, a polymer dispersed liquid crystal material, or another diffusive material. The diffusive element can be formed over the output window, or may comprise the output window of the spatial light modulator device. In any case, the diffusive element can slightly scatter the data encoded object beam, which can significantly reduce undesirable zero-order burning effects in a holographic medium positioned in proximity to a Fourier transform plane.

Abstract: A security camera has an adjustable turret that holds a lens assembly which can be aimed in various directions. The camera also has a compact housing which, in combination with the adjustable directionality of the turret, enables universal mounting to various structures and positions in an aircraft cabin. The camera operates in light and dark conditions, as the lens assembly is configured to focus visible and infrared light wavelengths onto a fixed focal plane. In an embodiment, the camera includes an infrared illumination source to illuminate a field of view during dark conditions. The lens assembly includes a rigid barrel with a pinhole aperture through which light enters a series of lens elements. An optical sensor is mounted to an opposite end of the barrel at the fixed focal plane to generate an electronic image signal, and the sensor is rotatably adjustable to yield a correct image orientation depending on the turret position.

Abstract: A lens body tube configured to support at least one lens inside an inner tube such that the at least one lens can be translated along the optical axis direction of the lens body tube includes a cam ring configured to be rotatably supported around the outer circumferential surface of the inner tube, the at least one lens being configured to be translated along the optical axis direction accompanied by the rotation of the cam ring, a plurality of cams provided on the inner circumferential surface of the cam ring, a plurality of cam followers provided on a lens frame supporting each of the at least one lens, each of the plurality of cam followers being engaged with a corresponding one of the plurality of cams through an opening provided on the inner tube, and a plurality of first protrusions, each of which is formed integrally with a corresponding one of the plurality of cams, and has contact with the outer circumferential surface of the inner tube.

Abstract: A lens barrel includes a lens-holding cylinder which supports a lens and is provided with a cam-follower and a rectilinear key; a cam-cylinder having a cam-groove which engages with the cam-follower so as to apply a driving force to the lens-holding cylinder in the optical-axis direction; and a guide cylinder which is enclosed by the cam-cylinder and has a rectilinear guide opening that engages with the rectilinear key so as to guide the lens-holding cylinder in the optical-axis direction. A segment of the cam-cylinder adjacent to an object to be photographed has a greater wall thickness such that the cam-cylinder has a level difference. A portion of the guide cylinder adjacent to an object to be photographed, which corresponds to the level difference of the cam-cylinder, is made thinner by the amount of the level difference.

Abstract: A zoom lens system includes a negative first lens element, a positive second lens element and a positive third lens element, in this order from the object. Upon zooming from the short focal length extremity to the long focal length extremity, the positive second lens element and the positive third lens element move along the optical axis, while the negative first lens element remains stationary. Furthermore, the positive second lens element is directed to move from the image side toward the object side.

Abstract: A zoom lens system having an exit pupil far away from the image plane, zoom ratio of about three, and in particular having compactness and high optical performance includes, in order from an object, a first lens group having negative refractive power, an aperture stop, a second lens group having positive refractive power, and a third lens group having positive refractive power. When zooming from a wide-angle end state to a telephoto end state, the first and second lens groups are moved and the third lens group is fixed such that a distance between the first lens group and the second lens group varies, and a distance between the second lens group and the third lens group increases. The second lens group is composed of four lenses or less and includes a diffractive optical surface formed on a lens surface except the most object side lens surface.

Abstract: An image-capturing lens includes a plastic lens formed with use of a material in which particles each having the maximum length of 30 nanometer or less are dispersed in a plastic material.

Abstract: A process for making a lenticular card including: providing an imaged transparent sheet having a first smooth side and a second side with a lenticulated region, the transparent sheet optionally having at least one printed image area on the first smooth side and a moisture cure adhesive layer over the printed image areas and non-image areas of the first smooth side, and the moisture cure adhesive layer being applied with a screen press through a screen; and combining the imaged transparent sheet on the adhesive layer side of the transparent sheet with a backing sheet by nipping the paired sheets with a nip roller. The invention also provides processes useful for preparing a lenticular card including an optional core sheet, or optional primer layers.