Abstract: An adaptive system and a method for adjusting a parameter in the adaptive system includes operating an adaptive system with an output signal produced from an input signal applied to an input, in which a parameter with a finite range is determined based on a difference between the output signal and a target output signal. In one example the parameter with the finite range is a fixed-point parameter or an analog parameter. The parameter is accessed from the adaptive system. A probability distribution of the parameter is assigned. The finite range for the parameter is updated based on the probability distribution which has been assigned. The probability distribution function may be updated alone with the finite range of the parameter. The probability distribution may be derived from one or more historical values of the parameter, and a plurality of system parameters belonging to an identical category of data as the parameter.

Abstract: The polyester film according to the embodiment can maintain its original characteristics even after a plurality of repeated folding by adjusting the deformed dimension as compared with the initial dimension of the film, in particular, by adjusting the ratio between the deformed dimensions in two in-plane directions perpendicular to each other to a specific range, in the cycle of straining and relaxing the film. Accordingly, the polyester film can be applied to a cover of a flexible display device, in particular, a foldable display device to exhibit excellent characteristics.

Abstract: An optical element includes an optical surface configured to receive light at a predetermined wavelength in a range from about 400 nm to about 1000 nm. The optical surface is defined by a vertical axis and a horizontal axis defining four Cartesian quadrants sequentially numbered in a counter-clockwise direction. A first longitudinal section of the optical surface is centered on the vertical axis and a second longitudinal section of the optical surface is centered on the horizontal axis. The first and second longitudinal section each extend across opposite edges of the optical surface and have a same substantially uniform retardance for substantially normally incident light. The optical element includes four discrete retarder sections. Each retarder section is disposed on a respective Cartesian quadrant of the optical surface and has a retardance difference from the substantially uniform retardance of the optical surface that is greater than zero.

Abstract: A dark-field inspection system may include an illumination source to generate an illumination beam, illumination optics configured to direct the illumination beam to a sample at an off-axis angle along an illumination direction, collection optics to collect scattered light from the sample in response to the illumination beam in a dark-field mode, a polarization rotator located at a pupil plane of the one or more collection optics, where the polarization rotator provides a spatially-varying polarization rotation angle selected to rotate light scattered from a surface of the sample to a selected polarization angle, a polarizer aligned to reject light polarized along the selected polarization angle to reject the light scattered from a surface of the sample, and a detector to generate a dark-field image of the sample based on scattered light from the sample passed by the polarizer.

Abstract: A camera including an aperture, an image recording device, a reflective polarizer disposed between the aperture and the image recording device, a partial reflector disposed between the reflective polarizer and the image recording device, and a quarter wave retarder disposed between the reflective polarizer and the partial reflector. The reflective polarizer is curved about two orthogonal axes.

Abstract: A lens is formed from at least two sections or bodies that are shaped to mate with each other, and a multilayer optical film is sandwiched between these two sections. Smooth surfaces of each section combine to provide a first optical surface of the lens, e.g., a concave, convex, or flat optical surface. The multilayer optical film includes a stack of polymer layers configured to selectively reflect light by constructive or destructive interference, at least some of the polymer layers being birefringent. The multilayer optical film may thus be or comprise e.g. a reflective polarizer and/or a narrow band or otherwise notched reflector. The multilayer optical film has an extended terminus that separates the smooth surfaces of the two sections. Any edge defects such as cracks or delaminations that may exist along the extended terminus are characterized by an average defect distance of no more than 100 or 50 microns.

Abstract: Embodiments include a method of making a metal organic framework membrane comprising contacting a substrate with a solution including a metal ion and contacting the substrate with a solution including an organic ligand, sufficient to form one or more layers of a metal organic framework on a substrate. Embodiments further include a defect-free metal organic framework membrane comprising MSiF6(pyz)2, wherein M is a metal, wherein the thickness of the membrane is less than 1,000 ?m, and wherein the metal organic framework has a growth orientation along the [110] plane relative to a substrate.

Abstract: The present invention relates to a method for manufacturing a thin polarizer, the method including: a step of preparing an unstretched polyvinyl alcohol-based film having a thickness of 20 ?m or less, in which a strength applied to stretch the film by 6 times is 4 N or more; and a single stretching step of forming a stretched polyvinyl alcohol-based film having a thickness of 10 ?m or less by stretching the unstretched polyvinyl alcohol-based film solely, and a thin polarizer manufactured by using the same.

Abstract: Provided is an optical layered body having excellent antistatic property and optical properties. An optical layered body including a light-transmitting substrate and a hard coat layer on at least one surface of the light-transmitting substrate, wherein the hard coat layer contains antimony pentoxide and a urethane resin, and the antimony pentoxide is dispersed in the hard coat layer while forming a three-dimensional net structure.

Abstract: Provided are a high luminance polarizing plate including a polarizing plate, a ?/2 retardation film having an in-plane retardation value ranging from 250 nm to 280 nm in a wavelength range of 450 nm to 650 nm that is laminated on one side of the polarizing plate, and a brightness enhancement film laminated on the ?/2 retardation film, a method of manufacturing the same, and a display device using the high luminance polarizing plate.

Abstract: An optical switch for performing high extinction ratio switching of an optical signal includes a beam polarizing element and one or more optical elements. The optical elements are configured to direct an optical signal along a first or second optical path based on the polarization state of the optical signal as it passes through the optical elements. The optical switch performs high extinction ratio switching of the optical signal by preventing unwanted optical energy from entering an output port by using an absorptive or reflective optical element or by directing the unwanted optical energy along a different optical path.

Abstract: A wavelength selective switch for selectively switching optical wavelength components of an optical signal uses both LCoS and MEMs switching technologies to improve device performance. Specific performance improvements may include more ports, better spectral performance and isolation, improved dynamic crosstalk, more flexible attenuation options, integrated channel monitoring and compressed switch heights.

Abstract: The present disclosure provides an optical component array and method of making an optical component array that can include a plurality of optical components useful for projection devices or other optical devices. The optical component array can be fabricated such that individual optical components having several elements can be assembled in a massively parallel manner and then singulated as individual optical components, and can result in a large reduction in manufacturing cost.

Abstract: A hybrid polarizer includes an absorbing element having a first major surface and a second major surface. The hybrid polarizer also includes a first birefringent reflective polarizer disposed on the first major surface of the absorbing element, the first birefringent reflective polarizer having a first pass axis and a first block axis. The hybrid polarizer further includes a second birefringent reflective polarizer disposed on the second major surface of the absorbing element, the second reflective polarizer having a second pass axis and a second block axis.

Abstract: There is provided a light-guide, compact collimating optical device, including a light-guide having a light-waves entrance surface, a light-waves exit surface and a plurality of external surfaces, a light-waves reflecting surface carried by the light-guide at one of the external surfaces, two retardation plates carried by light-guides on a portion of the external surfaces, a light-waves polarizing beamsplitter disposed at an angle to one of the light-waves entrance or exit surfaces, and a light-waves collimating component covering a portion of one of the retardation plates. A system including the optical device and a substrate, is also provided.

Abstract: A reflective film includes interior layers arranged to selectively reflect light by constructive or destructive interference, the layers extending from a first zone to a second zone of the film. The film has a first thickness and the interior layers provide a first reflective characteristic in the first zone; the film has a second thickness and the interior layers provide a second reflective characteristic in the second zone. The difference between the first and second reflective characteristics is not substantially attributable to any difference between the first and second thicknesses, which difference may be zero. Rather, the difference in the reflective characteristics is substantially attributable to reduced birefringence of at least some of the interior layers in one zone relative to the other zone. The film may also incorporate absorbing agents to assist in the manufacture or processing of the film. Related methods and articles are also disclosed.

Abstract: A polarization-modulating optical element consisting of an optically active crystal material has a thickness profile where the thickness, as measured in the direction of the optical axis, varies over the area of the optical element. The polarization-modulating optical element has the effect that the plane of oscillation of a first linearly polarized light ray and the plane of oscillation of a second line early polarized light ray are rotated, respectively, by a first angle of rotation and a second angle of rotation, with the first angle of rotation and the second angle of rotation being different from each other.

Abstract: The invention relates to an optical system for a microlithographic projection exposure apparatus, comprising an optical system axis (OA) and a polarization-influencing optical arrangement, wherein the polarization-influencing optical arrangement comprises a first polarization-influencing element, which is produced from optically uniaxial crystal material and has a first orientation of the optical crystal axis, the-first orientation being perpendicular to the optical system axis and a thickness that varies in the direction of the optical system axis, and a second polarization-influencing element, which is arranged downstream of the first polarization-influencing element in the light propagation direction, is produced from optically uniaxial crystal material and has a second orientation of the optical crystal axis, the second orientation being perpendicular to the optical system axis, and a plane-parallel geometry, wherein the second orientation is different from the first orientation.

Abstract: A method for polarizing an electromagnetic wave having a frequency of not less than 0.1 THz and not more than 0.8 THz using a polarizer includes steps (a) and (b). The step (a) includes preparing the polarizer. The polarizer includes: a sapphire single crystalline layer; and a CaxCoO2 crystalline layer. The CaxCoO2 crystalline layer is stacked on the sapphire single crystalline layer, a surface of the CaxCoO2 crystalline layer has a (100) plane orientation and the CaxCoO2 crystalline layer has a thickness of not less than 2 micrometers and not more than 20 micrometers. The step (b) includes irradiating the polarizer with the electromagnetic wave having a frequency of not less than 0.1 THz and not more than 0.8 THz to output an output wave having only a component parallel to a c-axis direction of the sapphire single crystalline layer.

Abstract: Having a layer B formed of a resin “b” having a negative intrinsic birefringence value; and layers A formed of a resin “a” having a positive intrinsic birefringence value and formed on both surfaces of the layer B, wherein the resin “b” includes a styrene-based polymer, the resin “a” includes a polycarbonate, and a difference in average refractive index between the resin “b” and the resin “a” is 0.01 or more.

Abstract: A polarization-modulating optical element consisting of an optically active crystal material has a thickness profile where the thickness, as measured in the direction of the optical axis, varies over the area of the optical element. The polarization-modulating optical element has the effect that the plane of oscillation of a first linearly polarized light ray and the plane of oscillation of a second linearly polarized light ray are rotated, respectively, by a first angle of rotation and a second angle of rotation, with the first angle of rotation and the second angle of rotation being different from each other.

Abstract: Presently described are multilayer optical films comprising an optical stack comprising at least one first birefringent optical layer; at least one (e.g. isotropic) second optical layer having a birefringence of less than 0.04 at 633 nm, and optionally at least one skin layer. The second layer, skin layer, or a combination thereof comprises a blend of at least one methyl methacrylate polymer and at least one styrene-acrylonitrile polymer.

Abstract: An optical probe for splitting a beam of light into multiple beams. The optical probe may comprise a first polarizing beam splitter having a first polarization axis, a second polarizing beam splitter having a second polarization axis orthogonal to the first polarization axis, a first half wave plate and a second half wave plate, and optionally a first birefringent phase plate, and a second birefringent phase plate. The first half wave plate may be located before first polarizing beam splitter, and the second half wave plate may be located after the first polarizing beam splitter, relative to the propagation of the light beam. The optical probe may further include a lens for collimating the four light beams. A profilometer includes the optical probe for splitting a beam of light into four light beams, and a scanner for traversing the optical probe over a surface of an element to be measured.

Abstract: An optical element includes a first and second stacked birefringent layers. The first birefringent layer includes local anisotropy patterns having respective relative orientations that vary over a first thickness between opposing faces of the first birefringent layer to define a first twist angle. The second birefringent layer includes local anisotropy patterns having respective relative orientations that vary over a second thickness between opposing faces of the second birefringent layer to define a second twist angle different than the first twist angle. Related devices and fabrication methods are also discussed.

Abstract: This invention provides a method for contactless fingerprint detection and verification comprising illuminating a fingerprint and directing a reflected light through an imaging system using liquid crystal panels and birefringent elements to polarize the light. A plurality of polarized images are captured and used to calculate the depth of structural features on the fingertip. A means to generate a two-dimensional rolled equivalent image of the fingerprint is also provided which may then be used for verification and authentication. The invention also provides an imaging system for carrying out the method.

Abstract: In order to produce a beam with a zero intensity axial ray or to produce a beam that when focused will produce an image of a doughnut shaped pattern with a zero intensity central point, a beam with a uniform or Gaussian profile is directed to a plurality of transparent plates, arranged in pairs on opposite sides of the beam axis, such that for at least one pair, the plates have a composition and thickness different from each other, and chosen so that the transmitted light has a has a phase difference of half a wavelength for at least three different wavelengths. An additional plate with a center on the perpendicular of the line connecting the first two plates has a composition and thickness such that the light transmitted through that additional plate has a phase difference of a quarter wavelength with respect to the light transmitted through one of the plates of said first pair of plates, at least one wavelength.

Abstract: An optical sheet including a plurality of optical anisotropic films is provided. The optical anisotropic films of the optical sheet are alternately stacked on one another. Each optical anisotropic film has a plurality of main axis refractive indexes nx, ny and nz. The main axis refractive indexes nx and ny are in-plane main refractive indexes, and the main axis refractive index nz is a thickness-wise refractive index. The main axis refractive index nx is the minimum or the maximum among the main axis refractive indexes nx, ny and nz. Each optical anisotropic film has an optcial axis, and a direction of the optical axis is the same to a main axis direction of the main axis refractive index nx. The optical axes of the optical anisotropic films sequentially rotates along a predetermined in a thickness direction, and a totally rotation angle thereof is greater than or equal to 360 degrees.

Abstract: An optical element includes at least two stacked birefringent layers having respective local optical axes that are rotated by respective twist angles over respective thicknesses of the at least two layers, and are aligned along respective interfaces between the at least two layers. The respective twist angles and/or the respective thicknesses are different. The at least two stacked birefringent layers may be liquid crystal polymer optical retarder layers. Related devices and fabrication methods are also discussed.

Abstract: The present invention discloses a polarization-maintaining reflector arrangement comprising a reflector group including at least one polarizing reflector and at least one compensating reflector, wherein the incident plane for the polarizing reflectors is perpendicular to the incident plane for the compensating reflectors, and the product of s-wave reflectance of all the polarizing reflectors and p-wave reflectance of all the compensating reflectors is equal to the product of s-wave reflectance of all the compensating reflectors and p-wave reflectance of all the polarizing reflectors. One or more reflector groups can be used in the light path. The invention can conveniently and effectively eliminate the polarization caused by reflection.

Abstract: Curved lenses configured to decode three dimensional content and method of fabricating the same. The lenses decode three-dimensional content displayed on televisions or computer monitors. Sheets from which the lenses are cut have either (i) a polarizing axis of 0 degrees relative to horizontal and one sheet has a retarder axis at ?45 degrees relative to horizontal and the other sheet has a retarder axis of +45 degrees relative to horizontal; (ii) a polarizing axis of ?45 degrees relative to horizontal and one sheet has a retarder axis at 0 degrees relative to horizontal and the other sheet has a retarder axis of 90 degrees relative to horizontal; or (iii) a polarizing axis of +45 degrees relative to horizontal and one sheet has a retarder axis at 0 degrees relative to horizontal and the other sheet has a retarder axis of 90 degrees relative to horizontal.

Abstract: A circular polarizer comprising a single linear polarizer producing a linear state of polarization and at least one phase retardation film layered with the single linear polarizer. In a first embodiment, the at least one phase retardation film includes at least one uniaxial A-plate phase retardation film and at least one uniaxial C-plate phase retardation film. In a second embodiment of the invention, the circular polarizer includes a linear polarizer and at least one biaxial phase retardation film layered with the linear polarizer. In another example of the circular polarize of the second embodiment, at least one uniaxial A-plate phase retardation film and/or at least one uniaxial C-plate phase retardation film is also layer with the linear polarize and the biaxial phase retardation film.

Abstract: One embodiment contemplates a polarization insensitive optical circuit constructed of an input/output signal separator, such as an optical circulator or a 1×2 or 2×2 coupler or N×M coupler, a polarization sensitive operator, and a polarization rotator reflector. In an alternate embodiment, the invention contemplates a polarization insensitive optical circuit including a polarization rotator reflector, and a polarization sensitive operator which may include, for example, a first polarization rotator, an operator/coupler, and a polarization beam combiner. Preferably, at least one of the components in the optical circuit is constructed integrally from the substrate upon which the optical circuit is based. For examples the polarization rotator and/or polarization sensitive operator may be monolithic.

Abstract: An imaging system having reduced susceptibility to thermally induced stress birefringence, comprising; a relay lens, which images the object plane onto an intermediate image plane; a projection lens, which images the intermediate image plane onto the display surface. The lens elements that are immediately adjacent to a relay lens aperture stop and a projection lens aperture stop are fabricated using glasses having a negligible susceptibility to thermal stress birefringence, and the other lens elements are fabricated using glasses having at most a moderate susceptibility to thermal stress birefringence as characterized by the thermal stress birefringence metric.

Abstract: A polarization-modulating optical element consisting of an optically active crystal material has a thickness profile where the thickness, as measured in the direction of the optical axis, varies over the area of the optical element. The polarization-modulating optical element has the effect that the plane of oscillation of a first linearly polarized light ray and the plane of oscillation of a second linearly polarized light ray are rotated, respectively, by a first angle of rotation and a second angle of rotation, with the first angle of rotation and the second angle of rotation being different from each other.

Abstract: The present invention relates to a low pass filter including a wave plate capable of modulating incident light serving as image information such that A-polarized light and B-polarized light orthogonal to the A-polarized light are at an equivalent light quantity level over a visible light region, i.e., a transmittance takes a value close to 50%. According to the low pass filter of the present invention, it is possible to appropriately reduce a moiré phenomenon generated by an image sensor constituting the optical low pass filter including the above-described wave plate, and suppress degradation of an image quality caused by light quantity deflection of a separated light beam, and the low pass filter of the present invention is therefore useful.

Abstract: A polarization-modulating optical element formed of an optically active crystal material has a thickness profile where the thickness, as measured in the direction of the optical axis, varies over the area of the optical element. The polarization-modulating optical element has the effect that the plane of oscillation of a first linearly polarized light ray and the plane of oscillation of a second linearly polarized light ray are rotated, respectively, by a first angle of rotation and a second angle of rotation, with the first angle of rotation and the second angle of rotation being different from each other.

Abstract: A retardation film composed of a laminated film which comprises a layer A composed of a material having a positive intrinsic birefringence and a layer B composed of a material having a negative intrinsic birefringence; the retardation film has a stretching temperature T? which causes delaying of a phase after the stretching to a phase before the stretching and a stretching temperature T? which causes hastening of a phase after the stretching to a phase before the stretching, in cases of uniaxially stretching in a direction of an X axis by draw ratio of 1.25, in which the phase is of linearly polarized light ?X in relation to linearly polarized light ?Y, the X axis is an uniaxially stretching direction; and the retardation film satisfies 0.92 ?R40/Re ?1.08, wherein Re (nm) and R40 (nm) are retardation values of light having a wavelength of 550 nm.

Abstract: An optical arrangement includes a polarization-modulating optical element and a compensation plate is disclosed. The polarization-modulating optical element includes a first optically active material having a first specific rotation with a sign, the polarization-modulating optical element having a first optical axis. The polarization-modulating element has a first thickness profile that, as measured in the direction of the first optical axis, that is variable. The compensation plate includes a second optically active material having a second specific rotation with a sign opposite the sign of the first specific rotation. The compensation plate has a second thickness profile configured so that, when radiation passes through the optical arrangement, the compensation plate substantially compensates for angle deviations of the radiation that are caused by the polarization-modulating optical element.

Abstract: An optical element includes a support plate composed of optically active material having an optic axis and at least two planar-parallel portions supported by the support plate, each of the at least two planar-parallel portions composed of optically active material having an optic axis. When a first linearly polarized light ray passes through a first section of the optical element along a direction parallel to the optic axes, a plane of oscillation of the first linearly polarized light ray is rotated by a first angle and when a second linearly polarized light ray passes through a second section of the optical element along a direction parallel to the optic axes, a plane of oscillation of the second linearly polarized light ray is rotated by a second angle different from the first angle.

Abstract: A beam steering apparatus includes a first beam steering stage and at least a second beam steering stage arranged in-line with the first beam steering stage. The first beam steering stage includes a first polarization grating comprising a uniaxial birefringent material having a first periodic director pattern, and the second beam steering stage includes a second polarization grating comprising a uniaxial birefringent material having a second periodic director pattern. In nonmechanical embodiments, a polarization selector may be arranged to provide a circularly polarized input beam incident on the first polarization grating. In mechanical embodiments, at least one of the first polarization grating and the second polarization grating may be operable to be independently rotated about an azimuth thereof. Related methods of operation are also discussed.

Abstract: Presently described are multilayer optical films, oriented polyester films, negatively birefringent copolyester polymers, fluorene monomers, and polyester polymers prepared from such fluorene monomers. In one embodiment, the multilayer optical film comprises at least one first birefringent optical layer; and at least one second optical layer having a lower birefringence than the first optical layer; wherein at least one of the optical layers comprises a negatively birefringent polyester polymer comprising a backbone and repeat units comprising at least one pendent aromatic group that is conformationally locked relative to the backbone.

Abstract: An elliptical polarizer with excellent viewing angle characteristics is provided which comprises at least a first polarizer, a first optical anisotropic layer, a second optical anisotropic layer, and a third optical anisotropic layer, laminated in this order, wherein the first optical anisotropic layer satisfies [1] 50?Re1?500, the second optical anisotropic layer satisfies [2] 0?Re2?20 and [3] ?500?Rth2??30, and the third optical anisotropic layer satisfies [4] 100?Re3?180 wherein Re and Rth indicate the retardation values in the plane and thickness direction, respectively, of each of the optical anisotropic layers.

Abstract: A hybrid polarizer includes an absorbing element having a first major surface and a second major surface. The hybrid polarizer also includes a first birefringent reflective polarizer disposed on the first major surface of the absorbing element, the first birefringent reflective polarizer having a first pass axis and a first block axis. The hybrid polarizer further includes a second birefringent reflective polarizer disposed on the second major surface of the absorbing element, the second reflective polarizer having a second pass axis and a second block axis.

Abstract: Curved lenses configured to decode three dimensional content and method of fabricating the same. The lenses decode three-dimensional content displayed on televisions or computer monitors. Sheets from which the lenses are cut have either (i) a polarizing axis of 0 degrees relative to horizontal and one sheet has a retarder axis at ?45 degrees relative to horizontal and the other sheet has a retarder axis of +45 degrees relative to horizontal; (ii) a polarizing axis of ?45 degrees relative to horizontal and one sheet has a retarder axis at 0 degrees relative to horizontal and the other sheet has a retarder axis of 90 degrees relative to horizontal; or (iii) a polarizing axis of +45 degrees relative to horizontal and one sheet has a retarder axis at 0 degrees relative to horizontal and the other sheet has a retarder axis of 90 degrees relative to horizontal.

Abstract: The disclosure relates to an optical system of an illumination device of a microlithographic projection exposure apparatus, including at least one first light-conductance-increasing element having a plurality of diffractively or refractively beam-deflecting structures extending in a common first preferred direction the light-conductance-increasing element having an optically uniaxial crystal material in such a way that the optical crystal axis of the crystal material is substantially parallel or substantially perpendicular to the first preferred direction.

Abstract: A reflective film includes interior layers that selectively reflect light by constructive or destructive interference, the layers extending from a first to a second zone of the film. In the first zone the layers provide a first reflective polarizer characteristic, and in a second zone the layers provide a substantially different reflective polarizer characteristic. The second zone is characterized by at least some of the layers having a reduced birefringence relative to their birefringence in the first zone. In some cases the first reflective polarizer characteristic may have a pass axis that is substantially orthogonal to that of the second reflective polarizer characteristic. The film may have substantially the same thickness in the first and second zones, or a substantially reduced thickness in the second zone relative to the first zone.

Abstract: An optical device obtained by bonding a first transparent member having a birefringent property to a second transparent member having a birefringent property. A dielectric multilayer film having no influence on the transmittance of light is formed on at least one of the bonding surfaces of the first and second transparent members. The bonding surface of the first transparent member is bonded through the dielectric multilayer film to the bonding surface of the second transparent member by optical contact.

Abstract: An optical rotating plate has an optical rotating material layer. A phase plate is provided on a first surface side of the optical rotating plate and has at least one birefringent material layer. The first surface side is disposed toward an emitting side of an optical path, thereby giving different phase differences to a first linearly polarized light group containing at least a linearly polarized light having a first wavelength and a second linearly polarized light group containing at least a linearly polarized light having a second wavelength which is different from the first wavelength.

Abstract: First and a second wave plates using quartz crystal having birefringence are laminated together in such a manner that their optical axes intersect to form a laminated wave plate functioning as a half-wave plate as a whole. Phase differences of the first and the second wave plates relative to an ordinary ray and an extraordinary ray with respect to a predetermined wavelength ? are set to be ?1 and ?2, an order of a high-mode order is set to be a natural number n, whereby the high-order mode laminated half-wave plate is formed so as to satisfy: ?1=180°+360°×n; and ?2=180°+360°×n.

Abstract: A first and a second wave plates using quartz crystal having birefringence are laminated together in such a manner that their optical axes intersect to form a laminated wave plate functioning as a half-wave plate as a whole. Phase differences of the first and the second wave plates relative to an ordinary ray and an extraordinary ray with respect to a predetermined wavelength ? are set to be ?1 and ?2, an order of a high-mode order is set to be a natural number n, whereby the high-order mode laminated half-wave plate is formed so as to satisfy: ?1=180°+360°×n; and ?2=180°+360°×n.