Abstract: There is provided a semiconductor laser comprising an n-InP substrate 1; a multilayer film including a strained MQW active layer 6 on the n-InP substrate 1; a p-electrode 18 on the multilayer film; a pair of grooves 15 separating the multilayer film in both edges of the p-electrode 18 and extending to the n-InP substrate 1; and a plurality of diffraction gratings formed in an area from one to the other of the pair of grooves 15 in a diffraction grating forming surface formed in the upper surface of the n-InP substrate 1 or the upper surface of any of the semiconductor films in the multilayer film.

Abstract: The present invention relates to an optical mask at low cost and so on having a structure capable of reducing further a peak of beam intensity caused by diffraction. The optical mask is constructed by overlapping a first mask and a second mask. The first mask and second mask each are a serrated aperture mask. The schematic shapes of the respective apertures of the first mask and second mask are almost rectangular and identical to each other. The fringe defining the aperture of the first mask is machined in a serrated shape, and the fringe defining the aperture of the second mask also is machined in a serrated shape. In the optical mask, the first mask and second mask are overlapped so that the serrations of the fringes defining the respective apertures of the first mask and second mask are located alternately.

Abstract: The specification and drawings present a new method, apparatus and software product for illuminating different graphical layouts in a component comprising an optical device, e.g., in a keyboard or in a liquid crystal display of an electronic device. The optical device uses a diffractive planar waveguide comprising diffraction gratings disposed on a lightguiding plate and the property that a short period diffractive grating has no diffraction orders at certain conical angles. Therefore, the out-coupling gratings on the waveguide are designed so that the optical beam coming from a certain direction can be effectively coupled out of the waveguide or be kept confined inside of the waveguide due to a total internal reflection. Then different graphical layouts can be disposed on the waveguide using, e.g., pixels having diffraction gratings with periodic lines at different orientations. Multiple substrate (waveguide) arrangements are described.

Abstract: In the diffraction grating low-pass filter, the diffraction grating has a refractive index variation region having a refractive index different from that of the glass substrate and having a lattice shape in the glass substrate, and the refractive index variation region includes a plurality of phases depending on differences of optical path lengths. Furthermore, in the diffraction grating low-pass filter, a region having an array of two rows and two columns in which regions of phases 0 and 2? are arranged in one diagonal direction and regions of phases ? and 3? are arranged in the other diagonal direction is set as a unit grating.

Abstract: The diffractive optical element includes a first diffraction grating and a second diffraction grating, which are formed of materials different from each other, the first diffraction grating and the second diffraction grating are stacked so as not to provide any air layer therebetween. The diffractive optical element satisfies conditions of nd1<nd2, ?d1<?d2, 1.65?nd1, ?d1?20, 1.73?nd2, and 15??d2?60 where nd1 and ?d1 respectively represent a refractive index and an Abbe constant of the material of the first diffraction grating for a d-line, and nd2 and ?d2 respectively represent a refractive index and an Abbe constant of the material of the second diffraction grating for the d-line. The element is capable of reducing deterioration of a diffraction efficiency by an obliquely incident light, to improve the diffraction efficiency of a designed order light in a use wavelength range.

Abstract: A light-condensing device and a method of fabricating the same are provided. The light-condensing device includes a central block, a pair of vertical diffraction grating blocks respectively located left and right of the central block, and a pair of horizontal diffraction grating blocks respectively located above and below the central block. The vertical diffraction grating blocks include parallel vertical diffraction gratings in the form of lines extending in the direction of a vertical axis, and the horizontal diffraction grating blocks include parallel horizontal diffraction gratings in the form of lines extending in the direction of a horizontal axis.

Abstract: Methods and structures for reducing and/or eliminating moisture penetration in an optical package. The optical package may include (1) a layer of inorganic material placed over the points of the optical package susceptible moisture penetration of the optical package; (2) a portion of hygroscopic material placed over the points of the optical package susceptible to moisture penetration; (3) a layer of hygroscopic material placed on the interior surface of the optical package; and/or (4) a layer of hydrophobic material coated on the optical surfaces of the optical package.

Abstract: An optical module according to the invention can achieve an optical system using a transmission-type diffraction grating for bending the optical path of incident light with a specific wavelength by about 90°. A substrate of the transmission-type diffraction grating is mounted at an angle in a range of +5° with respect to the design incident angle ? of the incident light. The optical system can be applied to a light multiplexing/demultiplexing module.

Abstract: The invention provides a diffractive optical element that can be used as a light beam splitter device, an optical low-pass filter or the like having a two-dimensionally multi-valued fine periodic structure. The surface of a transparent substrate for the diffractive optical element is divided into fine rectangular areas of identical shape which line up in two orthogonal directions while a plurality of rows line up with ends in alignment in any one of the directions. With respect to standard wavelength light incident vertically on the surface of the transparent substrate, an l-th, and a (l+1)-th rectangular area in an l-th row, where l is an odd number, gives a phase 2p?, and a phase {(4q+1)?/2+??/2}, respectively, and an l-th, and a (l+1)-th rectangular area in a (l+1)-th row gives a phase {(4r+3)?/2+3??/2}, and a phase {(4s+2)?/2+??}, respectively. However, ?0.25???0.25, and p, q, r, and s is an integer.

Abstract: A spill light removing device includes a first blocker which is located perpendicularly to a stream route of light being irradiated from a light source and blocks a stream of light that is incident to the surface of the first blocker, except on a hole formed on the first blocker; a pass-through tunnel which is connected to the hole and is formed in the same direction to the stream route of light and allows the stream of the light to pass through; and a second blocker which has a irregularity pattern that is formed on a inner wall of the pass-through tunnel and reflects the light that is incident in the deviated direction of the stream route of light.

Abstract: A light detecting apparatus which can be arranged even in an optical path of which converting angle is relatively large, and can accurately detect light entering along a predetermined direction in an optical path. The light detecting apparatus (10) for detecting light which enters in a predetermined direction in an optical path has a light splitting element (11) having two optical surfaces (11a, 11b) positioned in the optical path, and a photoelectric detector (12) for photo detecting light which propagates inside the light splitting element and which is guided from a side face (11c) of the light splitting element. The light splitting element further has an incident angle conversion section (13) for converting a part of light which enters one optical face of the light splitting element into light entering the other optical surface at an incident angle greater than or equal to a total reflection angle.

Abstract: The present invention relates to an optical security marking component producing a first visible configuration when observed through a polarizer oriented in a first orientation, and a second configuration, separate from the first, visible when observed through the polarizer oriented in a second orientation, the optical component comprising a stamped film for forming at least two diffraction gratings having different orientations, characterized in that each of said gratings has a period of less than 550 nm and a modulation between 0.25 and 0.5 relative to a reference plane.

Abstract: An optical system is presented that enables images of a wide range of natural subjects to be well reproduced with their colors, and provides an image pickup system including, at least, an image pickup optical system, an electronic image pickup device having three or more different spectral characteristics to obtain a color image, and a controller for implementing signal processing or image processing on the basis of an output from the electronic image pickup device. The optical element that takes part in determining the focal length in the image pickup system includes an optical element making use of a refraction phenomenon alone.

Abstract: An optical system enables images to be well reproduced with their colors, and provides an image pickup system including an image pickup optical system, an electronic image pickup device to obtain a color image and a controller for implementing signal processing or image processing on the basis of an output from the electronic image pickup device. The optical element that takes part in the determination of a focal length includes an optical element making use of a refraction phenomenon alone. The 400-nm wavelength input/output ratio is 10% or less with respect to an input-output ratio for a 400-nm to 800-nm wavelength at which an output signal strength ratio with respect to an input quantity of light is highest when the input quantity of light is defined by the quantity of a light beam emanating from the same object point and entering the image pickup optical system and the output signal strength is defined by the strength of a signal produced from the controller in response to the light beam.

Abstract: The present invention relates to tunable filters. More specifically, the present invention pertains to a method and apparatus that allows tuning of a wavelength over a large optical band. The disclosed system and method allows an arbitrary wavelength selection of an incoming beam of light. The disclosed system and method may be used in imaging systems like telescopes or microscopes, or for point sources like laser or optical fibers. Further, in the case of optical fibers, it may be used as an add/drop filter.

Abstract: A grating has a high diffraction efficiency into the minus first diffracted order in transmission, for both TE and TM polarizations. The incident angle may optionally be chosen so that the minus first diffracted order in reflection would be retroreflected back to the incident beam. The grating may be formed from various materials and/or layers, where the thicknesses of the individual layers may be determined by an optimization or simulation process. In one aspect, the grating may have four or more layers, formed with three or more materials. In another aspect, the grating may have a longitudinal refractive index profile that contains at least two local extrema, such as a maximum and/or minimum. Such a grating may be formed from three or more materials, two materials, or a single material that has a continuously varying refractive index. Any or all of the materials may have a continuously varying refractive index profile, as well.

Abstract: A diffractive optical element includes at least a first diffractive element and a second diffractive element. The conditional expression 0.5?D/DS?0.9 is preferably satisfied where DS denotes the summation of the optimum designed groove height of the first diffractive element d1S and that of the second diffractive element d2S, and D denotes the summation of an actual groove height of the first diffractive element d1 and that of the second diffractive element d2. At least one of the first diffractive element and the second diffractive element is made of glass. At least one of the first diffractive element and the second diffractive element is made of resin. The optimum designed value of groove heights of the diffractive optical element are determined so as to satisfy a condition for correcting chromatic aberration at both d-line and g-line.

Abstract: An optical device and a wavelength selector switch are provided. The optical device includes a diffraction grating having first and second planes and first and second reflecting planes located on a first plane side of the diffraction grating. In the optical device, light input to the second plane of the diffraction grating is diffracted, and then an optical path of the diffracted light is re-input to the first plane of the diffraction grating newly via the first and the second reflecting planes.

Abstract: A diffraction grating device for splitting or coupling light beams permits the divergence of the light beams to be minimized easily. A first light beam is incident on a diffraction grating from the side thereof facing the inside of the device, and a second light beam is incident on the diffraction grating from the side thereof facing air. The diffraction grating transmits the first light beam by diffraction of the minus first order so that it travels in the reverse direction along the optical path of the second light beam before incidence, and transmits the second light beam by diffraction of the zero order. The second light beam, transmitted by diffraction of the zero order, spreads over a certain width of wavelengths, but does not diverge even after diffraction.

Abstract: An optical module can achieve an optical system using a transmission-type diffraction grating for bending the optical path of incident light with a specific wavelength by about 90°. A substrate of the transmission-type diffraction grating is mounted at an angle in a range of ±5° with respect to the design incident angle ? of the incident light. The optical system can be applied to a light multiplexing/demultiplexing module.

Abstract: One exemplary metamaterial is formed from a plurality of individual unit cells, at least a portion of which have a different permeability than others. The plurality of individual unit cells are arranged to provide a metamaterial having a gradient index along at least one axis. Such metamaterials can be used to form lenses, for example.

Abstract: The present invention provides a light guide plate which can process in polarization separation, and emit a light in a desirable direction, a surface light source device, and a liquid crystal display device.

Abstract: A light diffusion arrangement, for a photographic device having a flashlight, includes a diffuser housing, a plurality of diffracting mesh members, and a plurality of light diffusing elements. The diffuser housing has a light-admissible surrounding sidewall radially extended from a base portion to define a light diffraction cavity. The diffracting mesh members are integrally formed on an inner side surface of the surrounding sidewall of the diffuser housing, while the light diffusing elements are integrally formed on an outer side surface of the surrounding sidewall of the diffuser housing, wherein the diffracted light is arranged to impinge on the light diffusing elements from the light diffraction cavity, in such a manner that each of the light diffusing elements is adapted to diverge the diffracted light for diffusing the diffracted light, so as to provide a uniform light diffusion effect as an optimal lighting effect for the photographic device.

Abstract: An image sensor includes at least one photoelectric conversion area on a semiconductor substrate, a color filter over the photoelectric conversion area, and an apochromatic microlens over the color filter.

Abstract: A diffraction grating structure comprises a substrate having a first surface and a second surface opposite to the first surface. A first grating is defined on the first surface and a second grating is defined on the second surface. The first grating includes a plurality of first grooves and has a first grating period. The second grating includes a plurality of second grooves and has a second grating period. The first groove and the second groove are formed by a fast tool servo system.

Abstract: A diffractive optical element has a diffraction grating which multiplexes light beams of different wavelengths, and the diffraction grating has a binary structure in which the diffraction surface top part and the diffraction surface bottom part repeat a concave and convex shape through a rising surface part along an optical axis direction P. The diffraction surface top part and the diffraction surface bottom part are inclined to the rising surface part. By this diffractive optical element, the diffraction angle of the light beam is maintained, and the diffraction efficiency of the light beam can be improved. By using this diffractive optical element in an optical communication module, while the separation angle of the light beam of the different wavelength is maintained, the signal receiving performance is increased.

Abstract: A diffractive optical element whose two diffraction gratings diffract three different wavelength light beams is provided. The diffractive optical element includes a first diffraction grating and a second diffraction grating that is located opposite the first one, and is configured in such a way that, among three different wavelength incident light beams, the diffraction efficiency in one light beam diffracted on the first diffraction grating is a predetermined value or less, and the diffraction efficiencies in the other two different incident light beams diffracted on the second diffraction grating are predetermined values or less. This arrangement can achieve a diffractive optical element capable of diffracting the three different wavelength light beams in a simple configuration.

Abstract: A transmission diffraction optical element is presented in which ridges having a roughly rectangular cross-section shape are disposed parallel to each other at a regular pitch at the surface of a substrate. Striped thin-film layers are formed on these ridges and a thin-film layer is inserted between the substrate and the ridges. The thin-film layers are arranged at a regular pitch identical to the regular pitch of the ridges and the thin-film layer does not have a periodic pattern oriented in the same direction as the periodic pattern of the ridges.

Abstract: The invention discloses a diffractive device and a method of creating the same displaying a three-dimensional preferably achromatic image, especially imitating a real or an imaginary relief scene, a flat microrelief or otherwise modulated structure (10) of a diffractive type is created, the structure (10) comprising system of diffraction zones (5) which are arranged so that in places of diffractive structure (10) corresponding to places of the relief scene (11) the diffraction zones (5) have such periodicity and orientation (a, b) that cause deflection of incident light (9) in the same direction as the relief scene (11) deflects an incident light, thus achieving a visible thee-dimensional and largely achromatic sensation of image, corresponding to the relief scene (11), when observing the diffractive structure (10) regardless of conditions of lighting.

Abstract: A three-dimensional display device including a display panel and a modulatable electrowetting grating is provided. The display panel has a plurality of pixels. The modulatable electrowetting grating is disposed on the display panel, and has a plurality of electrowetting light valves corresponding to the pixels.

Abstract: A diffraction grating with periodically arranged protrusions and grooves at a relatively narrow pitch and improved diffraction efficiency is disclosed. The protrusions of the grating are made of a material whose index of refraction is greater than that of the grooves, and the ratio of the width D of the protrusion to the pitch ? of the protrusion is set equal to or less than 0.4 (D/??0.4).

Abstract: An optical element includes a transparent substrate, a filter film, and an moth-eye grating structure. The filter film and the moth-eye grating structure are formed on two facing away surfaces of the transparent substrate. The moth-eye grating structure is configured for promoting anti-reflection properties to the moth-eye grating structure.

Abstract: An optical apparatus (10) is described, having at least one objective element (20) which has two or more objective lens elements (21, 24, 27), wherein one of the objective lens elements (21) is designed as a support lens element for a diffractive optical element (15), the support lens element having a diffractive optical element (15). In order to create an optical apparatus (10), with which a particularly good correction of the chromatic magnification difference can be achieved, it is provided that the optical apparatus (10) is designed as a Galileo system or as a Kepler system, that the optical apparatus (10) has an ocular element (30) with at least one ocular lens element (31), that the diffractive optical element (15) is disposed in the optical apparatus (10) or designed in such a way that the light rays impinge on it at an angle of less than 20 degrees and that the diffractive optical element (15) has a minimum groove width h of more than 50 ?m, in particular, of more than 100 ?m.

Abstract: In a diffraction grating element 10, between a first medium 11 and a fourth medium 14, a second medium 12 and a third medium 13 are disposed alternately to form a diffraction grating. The light, which enters the diffraction grating from the first medium 11, is diffracted at the diffraction grating portion and output to a fourth medium 14. Or, the light, which enters the diffraction grating from the fourth medium 14, is diffracted at the diffraction grating portion and output to the first medium 11. The index of refraction n1-n4 of each medium satisfies a relational expression of “n3<n1<n2, n3?n4?n2” or “n3?n1?n2, n3<n4<n2”.

Abstract: A spectral filter comprises a planar optical waveguide having at least one set of diffractive elements. The waveguide confines in one transverse dimension an optical signal propagating in two other dimensions therein. The waveguide supports multiple transverse modes. Each diffractive element set routes, between input and output ports, a diffracted portion of the optical signal propagating in the planar waveguide and diffracted by the diffractive elements. The diffracted portion of the optical signal reaches the output port as a superposition of multiple transverse modes. A multimode optical source may launch the optical signal into the planar waveguide, through the corresponding input optical port, as a superposition of multiple transverse modes. A multimode output waveguide may receive, through the output port, the diffracted portion of the optical signal. Multiple diffractive element sets may route corresponding diffracted portions of optical signal between one or more corresponding input and output ports.

Abstract: Disclosed herein is a raster scanning-type display device using a diffractive optical modulator. The raster scanning-type display device includes an optical illumination unit, a diffractive optical modulator, and a projection unit. The optical illumination unit radiates light, which is emitted from a light source, in a spot beam form. The diffractive optical modulator causes an element to modulate the spot beam incident from the optical illumination unit, and generate diffracted light whose intensity is adjusted and which has a plurality of diffraction orders. The projection unit generates an image by projecting the diffracted light incident from the diffractive optical modulator onto a screen in a scanning spot beam form and performing raster scanning in which horizontal scanning and vertical scanning are alternated.

Abstract: A security device comprises a holographic or diffractive optically variable effect generating structure which, when viewed normally i.e. perpendicularly to the plane of the device, replays at least one composite image, the composite image being defined by at least a pair of discrete image elements, the structure being such that at least two of the discrete image elements of the composite image have different optimal replay angles.

Abstract: A diffractive grating element is divided into at least two different grating regions each having different diffractive properties and arranged on opposite sides with respect to a transition point to form a splitted grating structure. The diffractions generated by the at least two different grating regions are arranged to mutually compensate for the variation in the input angle of the incident light wave to the total diffraction efficiency of the at least one diffracted light wave that is arranged to propagate within the substrate.

Abstract: A diffraction grating recording medium including a waveguide layer and a grating structure layer is provided. The waveguide layer has a reflective surface and a light incident surface, in which a thickness of the waveguide layer is between 100 nanometers and 2 micrometers, and the reflective surface reflects a light that enters the waveguide layer from the light incident layer. The grating structure layer is disposed on the light incident surface of the waveguide layer, in which the grating structure layer has a plurality of diffractive elements, and the arranging period of the diffractive elements is between 50 nanometers and 900 nanometers.

Abstract: A sub-wavelength anti-reflective diffractive structure is incorporated with a base diffractive structure having a small period to form a high efficiency diffractive structure. In the high efficiency diffractive structure, the anti-reflective structure and/or the base diffractive structure are altered from their ideal solo structure to provide both the desired performance and minimize reflections.

Abstract: An optical pickup has a light source for emitting a plurality of laser beams with different wavelengths; and an objective lens for focusing the laser beams emitted from the light source on recording surfaces of plural types of information recording media. A diffractive lens structure is provided in a light path of the laser beam, the structure including ring zone areas divided by a plurality of phase steps for correcting a wavefront aberration of the laser beam, a diameter of an outermost phase step of the diffractive lens structure is smaller than a second largest effective diameter of effective diameters required for reproduction of the plural types of information recording media.

Abstract: This invention relates to a configurable diffractive optical element comprising an array of diffractive sub-elements having a reflective surface, wherein each sub-element has a controllable position with a chosen range, and in which a number of sub-elements are provided with a reflective grating with a number of chosen spectral characteristics.

Abstract: A compact spectrometer operable in a wavelength range of 4.5 or more microns includes an entrance slit, a collimating mirror, a grating, a focusing mirror and a first focal plane. At least some radiation passing through the slit follows an optical path in which at least some radiation passing through the slit is reflected by the collimating mirror onto the grating, which in turn reflects at least some radiation onto the focusing mirror, which in turn reflects and focuses at least some radiation at a first focal plane and onto the two-dimensional array of detectors. Each column in the two-dimensional array of detectors corresponds to a wavelength in the 4.5 or more micron range, the two-dimensional array includes a plurality of columns that collectively correspond to wavelengths spanning the 4.5 or more micron range, and each adjacent pair of columns in the two-dimensional array of detectors corresponds to two wavelengths that differ by an equal amount.

Abstract: The invention provides an optical device, including a light-transmissive substrate, and a pair of different, parallel gratings including a first grating and a second grating, located on the substrate at a constant distance from each other, each of the pair of parallel gratings including at least one sequence of a plurality of parallel lines, wherein the spacings between the lines gradually increase from one edge of the grating up to a maximum distance between the lines, and wherein the arrangement of lines in the second grating is in the same direction as that of the first grating. A system utilizing a plurality of such optical devices is also disclosed.

Abstract: A light redirecting solar control film includes a multilayer film that transmits visible light and reflects infrared light, and a light redirecting layer adjacent to the multilayer film forming a light redirecting solar control film. The light redirecting layer includes a major surface forming a plurality of prism structures.

Abstract: Disclosed are radiation-resistant zone plates for use in laser-produced plasma (LPP) devices, and methods of manufacturing such zone plates. In one aspect, a method of manufacturing a zone plate provides for forming a masking layer over a supporting membrane, and creating openings through the masking layer in a diffractive grating pattern. Such a method also provides depositing radiation absorbent material in the openings in the masking layer and on the supporting membrane, and then stripping the remaining portions of the masking layer. Then, portions of the supporting membrane not covered by the absorbent material are removed, wherein the remaining portions of the supporting membrane covered by the absorbent material form separate grates. Also in such methods, cross-members are coupled to the grates for holding positions of the grates with respect to each other.

Abstract: A diffractive optical element has a support and a plurality of diffraction structures. The latter are applied on the support and are binary blazed by being split into substructures so that the aspect ratio of the substructures varies locally within an individual diffraction structure. One or more substructures with a large aspect ratio inside an individual diffraction structure are replaced by at least one substitute structure whose aspect ratio is less than that of the replaced substructures.

Abstract: A hybrid lens system includes: a first lens with positive diffractive power, a second lens with negative diffractive power, a third lens with positive diffractive power, and a fourth lens with negative diffractive power. The first lens, the second lens, the third lens and the fourth lens are aligned in that order from an object side to an image side. The first lens is made from a glass material, each of the second lens, the third lens and the fourth lens is made from a plastic material. All of the four lenses are aspheric lenses.

Abstract: Novel methods are disclosed for designing and constructing miniature optical systems and devices employing light diffractive optical elements (DOEs) for modifying the size and shape of laser beams produced from a commercial-grade laser diodes, over an extended range hitherto unachievable using conventional techniques. The systems and devices of the present invention have uses in a wide range of applications, including laser scanning, optical-based information storage, medical and analytical instrumentation, and the like. In the illustrative embodiments, various techniques are disclosed for implementing the DOEs as holographic optical elements (HOEs), computer-generated holograms (CGHs), as well as other diffractive optical elements.

Abstract: According to one exemplary embodiment, an EUV (extreme ultraviolet) optical element in a light path between an EUV light source and a semiconductor wafer includes a reflective film having a number of bilayers. The reflective film includes a pattern, where the pattern causes a change in incident EUV light from the EUV light source, thereby controlling illumination at a pupil plane of an EUV projection optic to form a printed field on the semiconductor wafer. The EUV optical element can be utilized in an EUV lithographic process to fabricate a semiconductor die.