Abstract: There is provided a protective, diffusive film for use in a surface light source device provided with a lens film, said protective, diffusive film comprising: a transparent substrate layer; and a resin layer provided on the top surface and the under surface of the transparent substrate layer, the resin layers being free from fine particles and having fine concaves and convexes on the surface thereof, the difference in coverage between the resin layer provided on the top surface of the transparent substrate layer and the resin layer provided on the under surface of the transparent substrate layer being in the range of −20% to +20% in terms of the percentage of the coverage of one of the resin layers to the coverage of the other resin layer.

Abstract: An optical component includes a glass body having a spin axis. The glass body has a first plane and a second plane parallel to the first one. The spin axis passes through the glass body, and is substantially perpendicular to the normal direction of the first plane and the second plane.

Abstract: A 3D shape-measuring apparatus using biaxial anamorphic magnification comprises a light source that projects a light onto an object surface to be sensed. Via an electrical image-grabbing device, such as CCD camera, the light reflected from the object is grabbed to determine the coordinate locations sensed on the object. Before the electrical image-grabbing device, the light reflected from the object passes respectively through a curved reflecting mirror or an assembly of telecentric cylindrical lenses to adjust an image magnification along the light projection direction, and an assembly of cylindrical lenses to adjust an image magnification along a direction perpendicular to the light projection direction. Thereby, resolution nonuniformity with respect to near and far distance is resolved while the observable range of the CCD camera can further be efficiently changed into a measurable field.

Abstract: An optical system includes a first cylindrical optical element (lens or mirror), and a second cylindrical optical element positioned in a round-spot plane following the first cylindrical optical element. At least one of the cylindrical optical elements is rotatable about the optical axis, relative to the other cylindrical optical element. A collimated light beam is incident on the first cylindrical optical element. Rotating the cylindrical optical elements relative to each other allows changing the size of a round spot or scaling an image at a given output location. In one implementation, two positive-magnification cylindrical lenses of focal length f are separated by a distance 2f. Rotating one of the lenses about the optical axis changes the diameter of a round spot (or symmetrically scales an image) at a fixed position away from the second lens.

Abstract: An anamorphic lens for a digital projection display system comprising a projection lens and an optical axis has an anamorphic factor between 1.3 and 2.0. The anamorphic lens includes a first afocal part placed in front of the projection lens and a second part placed behind the projection lens. The first part comprises a plurality of lens elements configured for magnification in a first direction transverse to the optical axis. The second part comprises at least one element configured for magnification in a second direction perpendicular to the first direction.

Abstract: A rod lens array having a structure in which a large number of rod lens elements are combined into one unit while the large number of rod lens elements are arrayed in a plurality of rows.

Abstract: As the output of laser oscillators become higher, it becomes necessary to develop a longer linear shape beam for a process of laser annealing of a semiconductor film. However, if the length of the linear shape beam is from 300 to 1000 mm, or greater, then the optical path length of an optical system for forming the linear shape beam becomes very long, thereby increasing its footprint size. The present invention shortens the optical path length. In order to make the optical path length of the optical system as short as possible, and to increase only the length of the linear shape beam, curvature may be given to the semiconductor film in the longitudinal direction of the linear shape beam. For example, if the size of the linear shape beam is taken as 1 m×0.4 mm, then it is necessary for the optical path length of the optical system to be on the order of 10 m.

Abstract: A molded glass lens is taught that includes a molded two-dimensional reference surface at a first end of the lens body, a first molded optical surface that is longitudinally displaced from the two-dimensional reference surface, and a molded second optical surface at a second end of the lens body. The first and second optical surfaces may be plano, convex or concave. The molded two-dimensional reference surface is planar and preferable annular. By physically locating the lens with the molded two-dimensional reference surface and one of the first or second optical surfaces, the lens can be held in a given orientation. Thus, the molded reference surface at the end of the cylindrical body allows for accurate and safe capture, positioning, handling, and placement for subsequent finishing operations, allowing for the creation of one or more additional lens datums.

Abstract: An objective lens (1) for an optical disk, which focuses a light beam from a light source, is designed so that a third-order coma aberration generated when the objective lens is inclined at a unit angle is larger than a third-order coma aberration generated when the optical disk (2) is inclined at the unit angle, mounted on an actuator for inclining the objective lens according to an inclination amount of the optical disk, and used. With this structure, it is possible to obtain an objective lens for an optical disk that has a large numerical aperture and is easy to manufacture and assemble, and in which the third-order coma aberration generated when the optical disk surface is inclined owing to a warp or the like can be corrected by small inclination of the objective lens, so as to reduce a residual astigmatism, which is generated according to the inclination amount, after the correction.

Abstract: A molded glass lens is taught that includes a molded three-dimensional reference surface at a first end of the lens body, a first molded optical surface interrupting the three-dimensional reference surface, and a molded second optical surface at a second end of the lens body. The first and second optical surfaces may be plano, convex or concave. The molded three-dimensional reference surface is curvilinear and may be a spherical, aspherical or conical segment. The molded lens may include a second molded three-dimensional reference surface at the second end of the lens body. The molded three-dimensional reference surface is of a specified shape and location with respect to the first and second optical surfaces. By physically locating the lens with the molded three-dimensional reference surface and one of the first or second optical surfaces, the lens can be held in a given orientation.

Abstract: The invention relates to an imaging system for optical automatic analysers, especially fluorescence readers. On the sample side, the imaging system contains a cylindrical lens array and a prism array, which is arranged upstream of the cylindrical lens array. The prismatic effect of the prisms of the prism array lies in the direction of the cylinder axes of the cylindrical lenses. Together with a telescopic imaging system, the inventive imaging system creates a number of parallel cylindrical focussing volumes between the cylindrical lens array and a detector array, these focussing volumes being slanted towards the optical axis of the telescopic system in relation to the vertical. The arrangement enables the detection of fluorescence with a large aperture in one direction, and at the same time enables depth selective analysis of the fluorescence signal, especially the discrimination of the fluorescent radiation originating from the solution above.

Abstract: A molded glass lens is taught that includes a molded three-dimensional reference surface at a first end of the lens body, a first molded optical surface interrupting the three-dimensional reference surface, and a molded second optical surface at a second end of the lens body. The first and second optical surfaces may be plano, convex or concave. The molded three-dimensional reference surface is curvilinear and may be a spherical, aspherical or conical segment. The molded lens may include a second molded three-dimensional reference surface at the second end of the lens body. The molded three-dimensional reference surface is of a specified shape and location with respect to the first and second optical surfaces. By physically locating the lens with the molded three-dimensional reference surface and one of the first or second optical surfaces, the lens can be held in a given orientation.

Abstract: A bar code reader having two reading windows, i.e., a bottom window and a side window. An increased number of scanning lines are used for constituting scanning patterns for scanning bar codes, and the arrangement of the optical system is contrived to decrease the whole size of the bar code reader and, particularly, to decrease the depth of the bar code reader. A source of laser light, a splitter for splitting the laser beam emitted from the laser light source into two, a reflection mirror for transmitting one beam from the splitter to a polygon mirror, the polygon mirror which rotates to scan the incident laser beam, a mirror system for emitting the beam reflected by the polygon mirror through the reading window, and a focusing member for focusing the beam reflected by the bar code onto a detector that detects the beam reflected by the bar code, are arranged on the same line in the bar code reader. By using a concave mirror, furthermore, the beam reflected by the bar code is folded back to one detector.

Abstract: Irradiation system for generating modulated radiation comprising at least one laser (1) and at least one modulator (6), and imaging means which can image the radiation emerging from the laser (1) at least partially onto the modulator (6), the laser (1) in two directions (x, y) perpendicular to one another having a different divergence and the modulator (6) being able to effect modulation by means of at least partial diffraction of the light incident on it, the imaging means comprising a device (3) for optical beam transformation by which the divergence of the laser (1) in the first direction (x) can be interchanged with the divergence of the laser (1) in the second direction (y).

Abstract: An illuminated indication device for road traffic. A number of indicating points are formed with indicating lenses in or on an indicating surface. The indicating lenses have a light entry surface and a light exit surface and are illuminated by the rear face of the indicating surface, which has individually allocated light-emitting elements with a small diameter. One object of this invention is to make the indication device easier to read. The light entry surface and/or the light exit surface is shaped in such a way that the distribution of light intensity on the indicator surface extends further in a horizontal direction than in a vertical direction.

Abstract: An image pickup lens system according to the present invention includes a lens body having a positive power and a diaphragm which is unified with the lens body at a location between the first face and the second face of the lens body and of which inner cylindrical surface is disposed at a location of the inside of the lens body. Thus, the numbers of the elements of the image pickup lens system are decreased and the image pickup lens system can be produced accurately. Moreover, when the lens body and the diaphragm are unified each other, both optical axes of the lens body and the diaphragm can be very accurately adjusted and automatically adjusted. Thus, a work to adjust accurately those optical axes is not necessary so that the lens body and the diaphragm can be produced easily and speedy. Moreover, by disposing the actual diaphragm, this invention can prevent the occurrence of the stray light such a flare and a ghost and the like and can actually remove the stray light if it occurs.

Abstract: The present invention relates to a device for making grid structures in optical fibers. The device comprises a laser beam emitter directed toward the surface enveloping the optical fiber and beam converting elements, characterized by having at least one fan-shaped cylindrical lens. The optical fiber is placed in the beam's focal plane, and the beam converting elements are able to be displaced relative to the optical fiber.

Abstract: A method is disclosed for automated multiplex sequencing of DNA with an integrated automated imaging hybridization chamber system. This system comprises an hybridization chamber device for mounting a membrane containing size-fractionated multiplex sequencing reaction products, apparatus for fluid delivery to the chamber device, imaging apparatus for light delivery to the membrane and image recording of fluorescence emanating from the membrane while in the chamber device, and programmable controller apparatus for controlling operation of the system. The multiplex reaction products are hybridized with a probe, then an enzyme (such as alkaline phosphatase) is bound to a binding moiety on the probe, and a fluorogenic substrate (such as a benzothiazole derivative) is introduced into the chamber device by the fluid delivery apparatus.

Abstract: Where an object is irradiated and scanned with laser beams that have been shaped into a linear shape and are moved in their width direction, a cylindrical lens group that is used in an optical system has a cylindrical face having an interior angle X that is not equal to 90°. As a result, peaks of light interference can be prevented from being superimposed on each other, whereby striped irradiation unevenness formed in the longitudinal direction of the linear laser beams can be lowered.

Abstract: An imaging optical element is comprised of a gradient index rod lens 12 of which external peripheral surface is a smooth surface without being processed by means of a flare-cut treatment and a field limitation stop member 14 mounted on the lens surface at the incidence side thereof. As for the stop member, the length t thereof is: t>lo·D/2X (where, lo: a lens working distance, D: a rod lens diameter, X: a radius of field of view), whereby the angle of incidence of beam &thgr; at the center of the lens satisfies &thgr;<tan−1(X/lo). It is effective especially when an application thereof is made to a rod lens array comprised of a plurality of rod lenses arranged into an array.

Abstract: A lens system defined along an X-Y-Z coordinate system transforms an elliptical optical beam defined as exhibiting a first, fast axis component and a second, slow axis component, into an essentially circular optical beam. A first and a second lens intercepts the elliptical beam and a cruciform cylindrical lens is disposed to intercept the output from the second lens. The cruciform cylindrical lens has a fast lens and a slow lens, the fast lens having a first, front cylindrical surface oriented along the X axis of the coordinate system for magnifying the first, fast axis component, the slow lens having a second, rear cylindrical surface oriented along the Y-axis of the coordinate system for magnifying the second, slow axis component, wherein the magnifications are determined to provide an essentially circular output beam, the cruciform cylindrical lens disposed such that the optical beam exiting the second lens impinges the first, front cylindrical surface.

Abstract: A monolithic element has a substrate body and at least one macro-optical characteristic integral in a first portion of the optical element. A plurality of surface micro-structures are integral in a portion of the optical element. The micro-structures are designed to homogenize light passing through the optical element to produce a predetermined pattern of smoothly varying, non-discontinuous light exiting the optical element. The light exiting the optical element is therefore altered according to both the macro-optical characteristic of the optical element as well as the homogenizing characteristics of the micro-structures.

Abstract: An imaging optical apparatus comprising a gradient-index rod lens array and two transparent or light transmitting optical elements that are substantially identical in shape and imaging characteristics and which are provided in the object space and the image space in the optical path of said gradient-index rod lens array in such a way that they are symmetrical with respect to said gradient-index rod lens array.

Abstract: An optical system for image rotation comprises two Pechan prisms (8, 9) located on an optical axis (4) and a lens system located on the same optical axis. The two Pechan prisms (8, 9) can be rotated relative to each other around the optical axis (4). They are located next to each other without the interposition of lenses. The lens system comprises two lens subsystems (6, 7) that are located one on each side of the pair of Pechan prisms, and between which there exists a telecentric beam path.

Abstract: An illuminating system for the vacuum ultraviolet (VUV) microlithography (at 157 nm) is disclosed and has a VUV light source (1), refractive optical elements of fluoride, at least one microlens array (3, 5) functioning as an element for increasing the light conductance value, and at least one honeycomb condenser (7a, 7b). The honeycomb condenser is preferably configured of crossed cylinder lens arrays.

Abstract: The invention relates to a device for picture recording that is used in image sensors in robotics, navigation and surveillance systems. Said device comprises a lighting device having several series connected lasers as a light source and a dispersing lens as well as an optical element with which high luminance laser light is emitted while complying with safety regulations.

Abstract: The inventive lens is formed from an optical adhesive is used to collect light from a LED array. As the adhesive is dispensed, it is formed into the shape of a lens. The adhesive is then cured, and a lens is formed that covers the LED array. The inventive lens collects light that is emitted by the LEDs at extreme angles and directs the light to the scan location.

Abstract: A cylindrical lens is constructed by a plurality of optical elements for linearly imaging a laser beam. The cylindrical lens is fixed to an optical frame using an adhesive so as to prevent the adhesive from entering a gap between the optical elements.

Abstract: A method and apparatus for passively aligning microlenses and other optical elements and devices is disclosed herein. The method taught herein is particularly well suited to effect the passive alignment of cylindrical microlenses with other elements or devices, such as laser diodes. Cylindrical microlens structures formed in accordance with the principles of the present invention use a base substrate having one or more alignment sites. The alignment sites being formed using wafer scale fabrication techniques are formed with a high degree of precision, such that cylindrical microlenses fitted into the alignment sites are aligned with respect to each other and are positioned a proper optical distance from each other. These microlens structures can be constructed individually or constructed en masse enabling mass production of the microlens structures. Moreover, the microlens structures can be passively aligned with other optical elements.

Abstract: The invention relates to an optical array for symmetrization of the beam of multiple sequentially fixed adjacent laser diodes, their respective output radiation being asymmetrical in relation to a first and a second direction that are perpendicular to each other. A cylindrical lens with sufficient isoplanacy is mounted on the tilted optical axis (z axis), which is perpendicular to the plane predetermined by the two directions (x, y). The lens collimates and displaces the output beam bundle of the individual laser diodes in the first direction (x). The cylindrical lens is mounted downstream a directional element that deflects the beam bundle of the individual laser diodes in the second direction (y) with different deflecting angles respectively in such a way that the centers of gravity of the individual beam bundles converge at a predetermined spacing.

Abstract: An axiconic telescope that receives a collimated input light beams and includes a first axicon and second axicon. Depending on the distance between the two axicons, the input collimated beam is converted to a diverging conical wave front by the first axicon, which is re-collimated by the second axicon having an oppositely signed cone angle. The output of the telescope is a collimated beam having an annular cross section, with the annulus having a width of dependent on the diameter of the telescope. The axiconic telescope may be used to produce an output beam having annulus size that can be optimized to illuminate a portion of a transducer in an solid immersion lens or photon tunning method device that contributes evanescent waves to increase resolution of an optical device.

Abstract: An imaging optical system for a light beam scanning system for causing a light bundle deflected by a deflector to form an image on a predetermined surface to be scanned and causing the image of the light bundle to scan the surface at a constant speed is provided with an anamorphic lens for compensating for tilt of the deflecting surface of the deflector. The imaging optical system satisfies formula0.ltoreq..phi.1/.phi..ltoreq.0.1.vertline.M.vertline.+0.45wherein .phi.1 represents the power of the anamorphic lens in the main scanning direction, .phi. represents the power of the entire imaging optical system in the main scanning direction and M represents the lateral magnification when the deflecting angle by the deflector is 0.

Abstract: A light collector for directing light to a concentrated area on a target surface such as for use with a linear LED array used as an erase lamp in an electrophotographic printer. The collector includes a compound cylinder lens supported by a pair of reflecting members. The reflecting members reflect light rays from the LED array to the cylinder lens. The cylinder lens includes a lower surface for capturing the reflected light rays and a tongue extending from the lower surface for capturing light rays directly from the LED array. The cylinder lens directs and concentrates the captured light rays in a narrow line on a target surface.

Abstract: A beam-shaping optical system includes a light source, a plurality of plates, and a cylindrical lens disposed between the light source and the plurality of plates, wherein the plurality of plates and the cylindrical lens have an optical feature in which the light output from the light source is beam-shaped to have a desired shape in the cross-section of the light beam. An optical pickup using the beam-shaped light which is diverged by the optical system can obtain convergence light reflected from an optical storage medium. Since the convergence light transmitted through only one plate has astigmatism as it is, a separate lens is not used for light detection and uses a photo detector adapted for employing an astigmatic method, to perform a focussing servo.

Abstract: Method for passively aligning micro-optical lenses with other elements, and devices resulting therefrom. The method taught herein is particularly well suited to effect the passive alignment of cylindrical microlenses with other elements or devices, such as laser diodes. Cylindrical microlenses formed according to the principles of the present invention include at least one alignment member including at least one alignment surface. Urging the cylindrical microlens into intimate mechanical contact with the element to which it is to be attached, and its attachment thereto results in micro-optical devices formed with a minimum of skilled labor, which devices reflect a superior degree of optical perfection.

Abstract: A lens shapes a diverging laser diode beam, and particularly circularizes and collimates, or diverges, or converges the beam. The lens may be part of an optical system, or part of a laser diode assembly. The lens is constituted of a body, the opposite ends of which are spaced from each other. The surfaces of the ends may be toric with the toric centers being coincident with the optical axis. The surfaces also have curvature profiles which circularize and collimates, or diverges, or converges collimates the beam. The curvature profile of one of the first and second surfaces has a correction profile which is a function of Zernike polynomials, thereby reducing wavefront error of the beam exiting the lens. The correction profile is also a function of the offset of the laser diode from the optical axis (misalignment), thereby increasing the misalignment tolerances for beam to lens centering. The curvature profiles of the surfaces may have correction for astigmatism in the beam shape produced by the laser diode.

Abstract: According to one aspect of the present invention, a laser line generator system comprises a laser source providing a diverging laser beam and a single lens element intersecting the diverging laser beam. The single lens element has a negative optical power in one cross section and a positive optical power in another cross section. This single lens element shapes the diverging laser beam to provide a laser line at an object surface. According to a second aspect of the present invention, the lens element has a first surface that is adjacent to the laser diode. This first surface is a toroidal surface. According to one preferred embodiment of the present invention, the first surface is concave about a center of curvature in at least one cross section and, in this cross section the laser diode is located at the center of curvature.

Abstract: An apparatus is disclosed for aligning optical beams from a source to a destination. The apparatus comprises a first pair of cylindrical lenses comprised of a first cylindrical lens and a second cylindrical lens. The first and second cylindrical lenses are adapted to slide up and down or back and forth along first and second line segments. The first and second line segments can be parallel to each other. A second pair of cylindrical lenses is disclosed comprised of a third cylindrical lens and a fourth cylindrical lens. The third and fourth cylindrical lens are adapted to slide up and down or back and forth along a third and fourth line segments. The first, second, third, and fourth line segments can be parallel to each other. The first, second, third, and fourth cylindrical lenses can adapted to slide between an optical source and an optical destination. The first and second cylindrical lenses, and the third and fourth lenses respectively can be closely adjacent one another.

Abstract: A flexible lens assembly. The flexible lens assembly includes a long, flexible structural layer and a first optical layer coupled to the long, flexible structural layer. The optical layer is shaped to achieve a desired optical characteristic, wherein the flexible lens assembly exhibits diffraction limited optical characteristics, and wherein the flexible lens assembly is capable of being flexed in at least a 180.degree. arc while maintaining its diffraction limited optical characteristics. In one preferred embodiment, the flexible lens assembly is a flexible cylinder lens.

Abstract: A compact optical system for imaging an array of light emitters, particularly an individually addressable laser diodes array, onto a recording surface, whereby the image of each emitting region is spread in the cross direction to a width approximately equal to its length dimension. The system consists of a main non-anamorphic imaging lens assembly and a single cylindrical lens disposed between the array and the imaging lens assembly, with its focal line parallel to the array's centerline. There will occur a spread of the short dimension of the imaged emitting regions due to defocusing at the recording surface. Also, the numerical aperture of the emitted beams in the transverse axis is reduced prior to entry into the imaging lens assembly.

Abstract: A system for providing efficient coupling between an elliptical mode laser source and a single mode transmission fiber is disclosed. In one embodiment, the system comprises a cruciform cylindrical lens formed as a pair of perpendicular cylindrical lenses to provide for separate magnification of the "fast" diverging component (i.e., this component passes through a "fast" cylindrical lens) and the "slow" diverging component of the beam (i.e., this component passes through a "slow" cylindrical lens). By decoupling the magnification requirements of the components of the elliptical beam, the beam may be transformed into an essentially circular beam, appropriate for coupling into a single mode fiber. In one arrangement of the present invention, a coupling efficiency of approximately 90% is possible (as compared with prior art coupling efficiency of about 44%).

Abstract: A lens system for use with elliptical optical sources includes a spherical fiber lens disposed beyond a conventional confocal lens arrangement. The spherical fiber lens is disposed in the optical path at the point where the slow axis (X ray) crosses the fast axis (Y ray); the rays will be "circular" and will thereafter propagate as a circular wavefront. The coupling efficiency of such a system is thus improved from approximately 40% to over 80%. The radius of the spherical endface of the fiber lens may be adjusted to improve the coupling efficiency. The spherical fiber lens is easily formed by fusing a section of "coreless" silica fiber onto the endface of a conventional single mode fiber. The end of the silica fiber is thereafter prepared (by heating, etching, polishing, or laser machining, for example) to provide a spherical endface with the desired radius.

Abstract: A beam converting optical system is provided which is easy to position the optical elements, which has a comparatively short total length, and which has good aberration correction. A beam converting optical system converts light beams with an oval cross-sectional shape into parallel light beams with a substantially circular cross-sectional shape. A converting lens is provided which has at least one surface that is cylindrical. The horizontal cross section of the cylindrical surface of the converting lens is essentially non-circular. The converting lens may consist of two similar elliptic cylinder surfaces. The two ellipses are of the shape of a horizontal cross section of the two elliptic cylinder surfaces and have the same focal point.

Abstract: Lens systems for use in fingerprint detection systems employing frustrated total internal reflection are provided. The systems include an aperture stop and three lens units. The first lens unit has a positive power, is located on the object side of the aperture stop, and forms a telecentric pupil for the lens system. The second lens unit has a positive power, is located on the image side of the first lens unit, and forms a real image of the object. In certain embodiments, the third lens unit is located between the first and second lens units and has substantially afocal cylindrical power. In other embodiments, the third lens unit serves to correct the field curvature of the image contributed by the first and second lens units.

Abstract: A graded-index microcylindrical lens functioning in combination with a laser diode beam to change the divergence of the fast axis on an incoming laser beam from one divergence to another, but not to collimate the beam. In one embodiment of the present invention, the graded-index microcylindrical lens changes the divergence of one axis of the laser beam to be substantially equal to the divergence of the slow axis.

Abstract: Method for manufacturing cylindrical microlenses having exceptional optical properties, and the lenses manufactured according to the process. According to the present invention, a method is provided for fabricating cylindrical microlenses, the method comprising the steps of forming a glass preform by means of grinding at least one face thereof in the direction transverse to longitudinal axis of the lens, the preform having the shape of a cylindrical lens, and drawing the glass preform to reduce its cross-sectional dimensions while retaining its cross-sectional shape, thereby providing a cylindrical microlens with a high numerical aperture or other desirable characteristics. The drawing step may be facilitated by means of the application of heat to the preform. Further, the preform may be roughly formed to a shape intermediate to its finished form by casting, sintering, extruding, or other glass forming methodology.

Abstract: In one embodiment, the illumination system for a scanner incorporates an excimer laser whose square beam is incident upon a two-dimensional array of lenses. The light exiting the array is made incident on a long focal length lens for creating nearly parallel rays. The combination of the array and the long focal length lens causes the resulting square beam at the focal plane of the long focal length lens to have a substantially uniform intensity across its area. An array of cylindrical lenses receives these nearly parallel rays. The light output of the cylindrical lens array is then made incident on a first positive lens whose focal length is longer than the distance between the cylindrical lens array and the first positive lens. A second positive lens is located of the focal plane of the first positive lens. This results in all light rays from the cylindrical lenses which have the same angle to be focused at the same point on the second positive lens.

Abstract: Laser diode bars with a plurality of light emitting facets have the light from those facets coupled into corresponding fibers of a fiber optic bundle via a microlens having a superconic cross section. An improvement in energy coupling of the typically less than 85 percent to up to 95 percent is achieved.

Abstract: An optical element having an optical axis, and comprising a plurality of definable adjacent zones of optical material, each zone having a definable refractive index different from the refractive index of an adjacent zone and an Abbe number, the zones of optical materials being arranged parallel to each other to define a profile of refractive indices which is symmetric about a plane of symmetry along the optical axis of the element and parallel to the zones. In one embodiment the optical element is a spectrally invariant lens.

Abstract: In an objective lens for an optical head apparatus for reading or writing an information on a recording medium such as optical disc, astigmatism is added on axial wavefront aberration so that off-axis astigmatism is to be cancelled by the axial astigmatism. At least one surface of the objective lens is a toric or cylindrical surface, and a standard deviation of astigmatism component of axial wavefront aberration is defined as Wa is to be restricted in a range of 0<Wa<0.07.lambda. (.lambda. is a wavelength of a light to be used). When the objective lens moves in a radial direction of the optical disc, a light beam enters into the objective lens in an off-axis region where the aberration is compensated by the axial astigmatism.