Abstract: A hybrid lens with a high numerical aperture is described.

Abstract: The linear dispersion of a dispersive optical system is increased by: (a) employing a transmissive diffraction grating (6) as a dispersive element; and (b) passing light through the grating twice. A reflector (7) is used to achieve the double passage through the grating. The system can be used to disperse light into its composite wavelengths (e g., the system can be a wavelength demultiplexer) or to combine dispersed light at different wavelengths into composite light (e.g., the system can be a wavelength multiplexer). The system can be employed in wavelength division multiplexed (WDM) optical communication systems.

Abstract: The invention relates to microfluidic devices and methods that employ electromagnetic radiation to move a droplet of fluid on a fluid-transporting surface of a substrate. Typically, radiation of a particular wavelength is directed through a substantially transparent material, and the radiation imparts an optical trapping force to move the droplet. In addition, a means for reducing evaporative loss from the droplet may be provided.

Abstract: The present invention provides photonic devices utilized in optical telecommunications. The photonic devices include photosensitive bulk glass bodies which contain Bragg gratings, particularly with the ultraviolet photosensitive bulk glass bodies directing optical telecommunications wavelength range bands. Preferably the ultraviolet photosensitive bulk glass bodies are batch meltable alkali boro-alumino-silicate bulk glass bodies. One embodiment of the invention relates to an optical element including a transparent photosensitive bulk glass having formed therein a non-waveguiding Bragg grating; and a optical element optical surface for manipulating light. Desirably, the photosensitive bulk glass has a 250 nm absorption less than 10 dB/cm.

Abstract: A system and method for producing spectrally segmented images of object fields. In one embodiment the system includes an optical system that focuses light received from an object field along a focal plane with a field stop positioned within the optical system that has plural apertures for selectively transmitting the light from the object field. A diffractive element is positioned within the optical system to spectrally spread, along the focal plane, the light transmitted through the apertures. The apertures can be parallel slots or geometrically arranges holes. The plural apertures are spaced such that the spectrally spread light transmitted through any given aperture and incident upon the focal plane does not overlap on the focal plane with the light transmitted through any other aperture. The diffractive element may spread light across one or more directions. In one embodiment, a processor is coupled to a plurality of pixels in a focal plane array.

Abstract: An optical device includes a light-emitting element for irradiating light onto an information recording medium, a diffraction grating for splitting light emitted from said light-emitting element into a plurality of beams, a focussing member for focussing the plurality of beams onto the information recording medium, a deflection member for deflecting the plurality of beams after they have been reflected from the information recording medium; and a photodetector for receiving the plurality of beams after they have been deflected by the deflection member. The diffraction grating has a first grating region and a second grating region, which have different diffraction efficiencies. The zero-order diffraction light in the first grating region is used as the main beam for reproducing the information signal, and the +1-order or −1-order diffraction light in the second grating regions is used as sub-beams for reproduction of the tracking error signal.

Abstract: A first diffractive optical element pattern with a pattern pitch that is no greater than a wavelength of incident light is formed on a first main surface of substrate such as a glass plate. Second diffractive optical element patterns are formed at positions that are respectively incident to positive first-order diffracted light and negative first-order diffracted light produced by the first diffractive optical element pattern. Negative first-order diffracted light produced by each second diffractive optical element pattern is incident upon a boundary face of the substrate at an angle that is smaller than the critical angle, and so exits the substrate.

Abstract: A diffractive optical element has a plurality of diffraction structures for a certain wavelength. These each have a width measured in the plane of the diffractive optical element and a height measured perpendicularly thereto. The widths and the heights of the diffraction structures vary over the area of the diffractive optical element. An optical arrangement comprising such a diffractive optical element has, in addition, a neutral filter. The efficiency of such a diffractive optical element and of such an arrangement can be optimized locally for usable light.

Abstract: Microparticles 8 includes an optical substrate 10 having at least one diffraction grating 12 disposed therein. The grating 12 having a plurality of colocated pitches A which represent a unique identification digital code that is detected when illuminated by incident light 24. The incident light 24 may be directed transversely from the side of the substrate 10 with a narrow band (single wavelength) or multiple wavelength source, in which case the code is represented by a spatial distribution of light or a wavelength spectrum, respectively. The code may be digital binary or may be other numerical bases. The micro-particles 8 can provide a large number of unique codes, e.g., greater than 67 million codes, and can withstand harsh environments. The micro-particles 8 are functionalized by coating them with a material/substance of interest, which are then used to perform multiplexed experiments involving chemical processes, e.g., DNA testing and combinatorial chemistry.

Abstract: A lamellar volume grating operating in reflection and transmission and providing a substantially wavelength- and polarization-independent diffraction efficiency is disclosed. The lamellar grating has an approximately rectangular grating profile with a height-to-width ratio of the grooves or “teeth” advantageously greater than 2. The grating operates preferably in first order and can be implemented as an immersion grating. In particular, the lamellar volume grating described herein can be employed in an optical multiplexer/demultiplexer arrangement with small overall dimensions.

Abstract: The present invention discloses a dual-lens hybrid diffractive/refractive imaging system comprising: a first lens including a concave surface and a convex surface; and the second lens including a convex surface and a concave surface. The concave surface of the first lens is an objective surface facing the object. The convex surface faces the convex surface of the second lens, while the concave surface of the second lens faces the charge-coupled device (CCD) through a filter. Any surface of the first lens and the second lens is spheric or aspheric. Moreover, the imaging system comprises at least one diffractive surface, referred to as a hybrid diffractive/refractive surface, formed on any surface of the two lenses. Therefore, aberration is eliminated and image quality is improved without increasing the number of lenses.

Abstract: The device includes an oscillator (1) to generate an electrical signal of a predetermined frequency and a signal divider (2) to split the electrical signal into first and second signals. The frequency of the second signal is tripled by tripler (3) and the tripled second signal is recombined with the first signal at signal adder (9) to produce a combined electrical signal. This combined electrical signal drives a Mach-Zehndcr modulator (10).

Abstract: Systems and methods of the present invention are directed to an optical element that includes a diffraction grating, an inclined surface, good optical characteristics, and an optical element manufacturing metal die. The optical element manufacturing metal die is capable of injection molding of an optical element having a complex structure. Further, the optical element manufacturing metal die includes nestings that have a plurality of mirror surface forming portions. The pluralilty of mirror surface forming portions include a plurality adjoining pairs of mirror surfaces. The plurality of mirror surface forming portions are molded by two adjoining pairs of the plurality of adjoining pairs of mirror surface forming portions, which are formed on the same nesting. At least one of the plurality of mirror surface forming portions are formed by a mirror surface grinding method.

Abstract: An interferometer (100) for writing Bragg gratings comprising the means for splitting (112) a light beam (114) into two coherent beams (116, 118), and a first optical lens arrangement (106, 108, 110) for bringing the coherent beams to interference for writing the Bragg grating in a photosensitive material (122). The first optical lens arrangement is arraged, in use, to vary an angle &bgr; between the two interfering beams.

Abstract: A tunable chromatic dispersion and dispersion slope compensator that utilizes a Virtually Imaged Phased Array (VIPA), a rotating transmissive diffraction grating, and a mirror with different curvatures for different cross-sections is disclosed. The compensator in accordance with the present invention provides simultaneous tunable compensation of chromatic dispersion and dispersion slope utilizing a single apparatus. The amount of compensation is accomplished by rotating the transmissive diffracting grating and/or translating the mirror. A system which utilizes the compensator is thus cost effective to manufacture.

Abstract: The invention relates to a pattern (18) which is designed as a visually perceptive mosaic consisting of a plurality of surface elements (8; 9; 15; 16; 17) and which is embedded in a laminate (1) consisting of at least one transparent outer layer (2) and one protective layer (5). The surface elements (8; 9; 15; 16; 17) are transparent, scatter or reflect incident light (10) or diffract the incident light (10) to microscopic relief structures covered with a reflecting layer (3). An area (16) corresponding to at least one of the surface elements provided with a microscopic relief structure (4) has a ZOM structure (4′) with a profile height h which can be slowly modified in a pre-determined manner and a spatial frequency f. The product of a predetermined critical wavelength &lgr;G of the visible spectrum and the spatial frequency f is greater than or equal to 1.

Abstract: In one embodiment of the invention, a grating structure etched on a mirror substrate has a grating period causing diffracting, out of an optical path, a first incident radiation within a first band around a first wavelength. A multi-layer coating deposited on the grating structure reflects the first incident radiation, in the optical path, within the first band and a second incident radiation within a second band around a second wavelength. In another embodiment, a first multi-layer coating deposited on a mirror substrate reflects a first incident radiation within a first band around a first wavelength and a second incident radiation, in an optical path, within a second band around a second wavelength. A grating structure is deposited on the first multi-layer coating. The grating structure is etched to have a grating period causing diffracting, out of the optical path, the second incident radiation within the second band.

Abstract: An objective lens to converge a light flux having a working reference wavelength &lgr;0(380 nm≦&lgr;0≦450 nm) under a working reference temperature T0 onto an optical information recording medium equipped with a protective substrate having a thickness of 0.6 mm with almost no aberration. The diffractive structural section of the objective lens has a first compensating function to compensate a change amount &dgr;SA1 of the third-order spherical aberration component of wavefront aberration caused by a fluctuation of a working wavelength, a second compensating function to compensate a deviation &dgr;WD of a converged-light spot in an optical axis direction caused by a fluctuation of a working wavelength, and a third compensating function to compensate a change amount &dgr;SA2 of the third-order spherical aberration component of wavefront aberration caused by a change of a refractive index of the lens body.

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: Optical systems are provided. One such optical system includes an optical source that propagates a source beam of light. A diffracting component is optically coupled to the optical source and is operative to receive the source beam and produce a diffracted beam. A target is located to receive the diffracted beam. Additionally, a compensating system repositions at least one of the optical source, the diffracting component, and the target in response to a detected change in refractive index of a medium through which the diffracted beam propagates so that the diffracted beam continues to be received by the target. Methods and other systems also are provided.

Abstract: In order to improve a structure arrangement comprising a plurality of portions having a relief structure with an optical-diffraction effect, in particular for visually identifiable optical security elements for value-bearing documents, for example banknotes, credit cards, passes or cheque documents, or other articles to be safeguarded, in such a way that it can give a viewer an image impression which in particular is more homogenous and more brilliant than is possible with known structure arrangements, it is proposed that a predominant number of the portions is of strip or band configuration.

Abstract: A light dispersing device for dispersing a polychromatic input beam into a plurality of narrow-band output beams such that the output beams are directed in a wavelength dependent manner and such that the directions of the output beams are less affected by a change in temperature. The preferred embodiment of the device comprises a diffraction grating mounted to a surface of a prism. The grating and prism have dispersing characteristics that make the output of the device substantially insensitive to a change in temperature. In one embodiment, the device is adapted to reduce the angles between the input beam and the output beams at the grating, and thereby improve throughput efficiency.

Abstract: A diffraction grating providing reduced polarization dependent loss. The elements of pixels of the diffraction grating are fixed or actuated such that some grating elements are actuated to correspond to a positive polarization dependent loss and others are actuated to correspond to a negative polarization dependent loss. The pixels may include multiples of three grating elements or multiples of four grating elements. An electrostatic beam structure providing increased actuation in a direction away from a substrate may be used in a diffraction grating providing reduced polarization dependent loss.

Abstract: An optical device includes a plurality of metallic stripes, arranged in a substantially planar, subwavelength grating having a laterally varying, continuous grating vector, deposited on a substrate such as GaAs or ZnSe. When used as a polarizer, the device passes a laterally uniform polarized beam of electromagnetic radiation incident thereon with a predetermined, laterally varying transmissivity. When used to effect polarization state transformation, the device transforms a beam of electromagnetic radiation incident thereon into a transmitted beam having a predetermined, laterally varying polarization state. The device can be used to provide radially polarized electromagnetic radiation for accelerating subatomic particles or for cutting a workpiece. The device also can be used, in conjunction with a mechanism for measuring the lateral variation of the intensity of the transmitted beam, for measuring the polarization state of the incident beam.

Abstract: A method of determining coordinates for a storage medium includes: determining diffraction data from a plurality of diffraction patterns corresponding to diffractive markers of the medium; and combining the diffraction data to determine composite coordinates for the medium. The composite coordinates may include three translational coordinates and three rotational coordinates. The act of determining diffraction data may include shining a plurality of beams on a selection of the diffractive markers, and measuring the corresponding diffraction patterns in one or more photodetectors to determine the diffraction data. In this latter case the photodetectors may be segmented. The act of combining the diffraction data to determine composite coordinates may include solving a matrix system that couples the diffraction data and the composite coordinates. Each diffractive marker may include a pit. The storage medium may include a holographic storage medium.

Abstract: The invention relates to an illumination device for producing an illumination pattern (6) with a variable shape and luminous intensity to a target (5). The illumination device comprises at least partly translucent and light-reflecting optical piece (1), several light sources (3) producing a conical light pattern, fixed in such a manner that the position and angle of the same can be adjusted in relation to each other and/or to the optical piece (1), and an electronic control unit (4) that is electrically coupled to each light source (3) in such a manner that the intensity of the light produced by each light source (3) can be adjusted under the control of the control unit (4). The optical piece (1) is attached in such a manner that the light beams produced by the light sources (3) are arranged to propagate at least partly via the optical piece (1) to the target (5) to be illuminated.

Abstract: Fluoropolymers consisting of alternating perfluorocyclobutane and aryl ether linkages possess suitable properties for optical waveguides and other devices using refractive properties of the polymers. Perfluorocyclobutane (PFCB) polymers having aryl groups alternating on an ether chain have shown useful physical properties for optical waveguide applications. Processes for micromolding such polymeric films by replicating a pattern or image directly from a silicon master, rather than from a polydimethyl siloxane (PDMS) mold) are disclosed.

Abstract: A light-diffractive binary grating structure has a microscopic mesa structure (2) whose plateaux (5) are separated by valleys (4) of substantially rectangular cross-section, wherein the arrangement of the valleys (4) is periodically repeated. Within a period (T) of the mesa structure (2) at least N valleys (4) separate the plateaux (5), N being an integer and greater than 2. The mesa structure (2) is an additive superimposition of N phase-shifted rectangular structures which have the same period (T) of the mesa structure (2). Each of the rectangular structures has a phase shift such that the plateaux (5) of the one rectangular structure fall into the valleys (4) of the N−1 other rectangular structures. In addition the resulting mesa structure (2) has only a single valley between two plateaux (5), which is of a width greater than a seventh of the period (T).

Abstract: A lens system includes a lens, a grating and a non-periodic phase structure. The lens system is a-thermalised by a compensation of the temperature-dependence of the spherical aberration of the lens by the temperature-dependence of the spherical aberration of the non-periodic phase structure and the grating. The lens system is also a-spherochromatised by a compensation of the wavelength-dependence of the spherical aberration of the grating by the wavelength-dependence of the spherical aberration of the non-periodic phase structure.

Abstract: A method for erasing some or all of at least some of the grating elements of a grating inscribed in an optical waveguide such as an optical fiber or a cane structure (a more rigid optical waveguide), or, more generally, for selectively altering the index of refraction of a span of an optical waveguide, and products provided by the method. A temperature profile suitable for achieving a predetermined desired apodization (shaping of the grating strength) is determined, and then a focused laser beam, from for example a CO2 laser, is directed to a target site on the optical waveguide selected as a suitable point from which to direct the laser beam and so introduce heat into the optical waveguide. The laser beam is held on the target site only so long as is necessary to create at least a portion of the temperature profile.

Abstract: The invention concerns a light reflecting element comprising a substrate (10), a multilayer mirror (20) and optical coupling means (32, 40) comprising a diffraction grating (40); whereby the reflection coefficient of one polarization is damped without damping the reflection coefficient of the orthogonal polarization over a broad wavelength range and with a large tolerance on the optogeometrical parameters of the device.

Abstract: An optical element includes a substrate; a first diffraction grating disposed on the substrate and having a period that is shorter than a light wavelength used; and a second diffraction grating disposed on the first diffraction grating and having a period that is shorter than the light wavelength used. In the optical element, the melting point of a material of the first diffraction grating is higher than the melting point of a material of the second diffraction grating.

Abstract: A wearable display system to display an input image signal includes an objective lens, a grating, a waveguide, and an ocular lens. The objective lens magnifies the input image signal and the grating refracts the input image signal magnified by the objective lens at a predetermined angle. The waveguide transmits the input image signal refracted by the grating and the ocular lens magnifies the transmitted input image allowing a user to see the input image signal.

Abstract: In one embodiment of the invention, a grating structure etched on a mirror substrate has a grating period causing diffracting, out of an optical path, a first incident radiation within a first band around a first wavelength. A multi-layer coating deposited on the grating structure reflects the first incident radiation, in the optical path, within the first band and a second incident radiation within a second band around a second wavelength. In another embodiment, a first multi-layer coating deposited on a mirror substrate reflects a first incident radiation within a first band around a first wavelength and a second incident radiation, in an optical path, within a second band around a second wavelength. A grating structure is deposited on the first multi-layer coating. The grating structure is etched to have a grating period causing diffracting, out of the optical path, the second incident radiation within the second band.

Abstract: According to the present invention, a method is provided for manufacturing a polarization diffraction film, which comprises the steps of forming a film with a liquid crystal material containing a liquid crystalline polymer and a crosslinkable substance, fixing a cholesteric alignment formed with the liquid crystal material, crosslinking the liquid crystal material to form a liquid crystal film and providing a region exhibiting a diffraction-capability on at least a part of the liquid crystal film or polarization diffraction film or comprises the steps of forming a film with a liquid crystal material containing a polymeric liquid crystal and a crosslinkable substance, crosslinking the liquid crystal material in a cholesterically aligned state so as to form a liquid crystal film with a cholesteric alignment fixed and providing a region exhibiting a diffraction capability on at least a part of the liquid crystal film.

Abstract: A diffraction optical element including an element body having a large number of grooves formed on its surface to form a grating, and a grating shape adjusting layer deposited on a grating surface of the element body by oblique incidence or material particles onto the grating surface, wherein the grating shape adjusting layer per se is made of a reflecting film material By the grating shape adjusting layer, the contour shape of the resulting grating surface in a section perpendicular to a lengthwise direction of the grooves is made not similar to the sectional shape of the element body. A reflecting film may be formed on a grating shape adjusting layer made of another material. A reflecting film may be provided on the element body before a grating shape adjusting layer made of a transparent dielectric material is provided on the reflecting film.

Abstract: A layered diffractive optical element is disclosed, with which a high diffraction efficiency is attained over a broad region of used wavelengths, and with which diffraction light of unnecessary diffraction orders can be suppressed. A diffractive optical element of the present invention includes a plurality of diffraction gratings made of materials with different Abbe numbers, the plurality of diffraction gratings being layered with each other. Moreover, the partial dispersion ratio with respect to a g-line and a F-line of the material constituting at least one of the plurality of diffraction gratings satisfies the condition represented by a specified expression.

Abstract: A diffractive optical element is provided with a first basic diffractive element on which a ring-shaped diffraction grating is formed; and a second basic diffractive element on which a ring-shaped diffraction grating is formed; wherein a center of the ring-shaped diffraction grating of the first basic diffractive element is eccentric in the first direction with respect to the center of a contour of the first basic diffractive element, and a center of the ring-shaped diffraction grating of the second basic diffractive element is eccentric in the second direction with respect to the center of a contour of the second basic diffractive element.

Abstract: An auxiliary light projection apparatus used for focus detection has a laser beam generating device and a diffraction plate for diffracting a laser light from said laser beam generating device. The diffraction plate has micro lenses regularly arranged in vertical and horizontal directions. The curvature of each micro lens in the vertical direction is different from that in the horizontal direction. The pitch of arrangement of the micro lenses in the vertical direction is different from that in the horizontal direction. In addition, the height of the micro lenses is varied cyclically. The auxiliary light projection apparatus projects a diffraction light pattern of the laser light emergent from the diffraction plate to an object to be photographed, as a pattern used for focus detection.

Abstract: Techniques for increasing the percentage of light that is transmitted through optical inspection systems that operate in or near the ultraviolet and deep ultraviolet electromagnetic spectrums are described. Along with increasing the amount of light transmission, the techniques of the present invention also provide additional advantages such as reduction of ripple, increased ability to match inspection systems, and improving manufacturability. The techniques of the present invention involve using an auto-focus light source near the operational range of the inspection system and slightly raising the lower end of the operational range.

Abstract: A method for manufacturing a diffraction optical element, according to the present invention, includes the steps of: supplying a photocurable resin onto a surface of a light-transmitting molding die in which a grating pattern is formed on the surface; irradiating the photocurable resin with light having a first wavelength through the molding die so as to cure part of the photocurable resin; irradiating the photocurable resin with light having a second wavelength, which is longer than the firs wavelength, through the molding die so as to cure at least part of the photocurable resin; and removing the cured resin from the molding die.

Abstract: A diffractive optical element includes a diffraction optical part provided with a phase-type diffraction grating. The diffraction grating of the diffraction optical part has on the surface thereof minute uneven structure of which the period is substantially constant. The period is smaller than a wavelength used.

Abstract: In one embodiment of the invention, a grating structure etched on a mirror substrate has a grating period causing diffracting, out of an optical path, a first incident radiation within a first band around a first wavelength. A multi-layer coating deposited on the grating structure reflects the first incident radiation, in the optical path, within the first band and a second incident radiation within a second band around a second wavelength. In another embodiment, a first multi-layer coating deposited on a mirror substrate reflects a first incident radiation within a first band around a first wavelength and a second incident radiation, in an optical path, within a second band around a second wavelength. A grating structure is deposited on the first multi-layer coating. The grating structure is etched to have a grating period causing diffracting, out of the optical path, the second incident radiation within the second band.

Abstract: A tunable phase mask assembly for use in photoinducing an optical wavelength filter in an optical waveguide. The phase mask assembly includes a phase mask having a length extending between two opposite longitudinal ends. The phase mask has grating corrugations projecting from its surface and distributed with a periodicity along its length. The periodicity of the phase mask is tuned by reversibly changing its length between the two longitudinal ends, such as by compressing or stretching the mask. In this manner, the interference pattern of a light beam passing through the phase mask is also tuned, which allows to control the characteristics of a wavelength filter photoinduced using this phase mask assembly.

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: There are provided A zoom lens system comprising, in order from an object side, a first lens unit of negative refractive power, a second lens unit of positive refractive power, a third lens unit of negative refractive power, and a fourth lens unit of positive refractive power, wherein the zoom lens system zooming from a wide angle end to a telephoto end a separation between each lens units is varied so that conditional expressions D1W>D1T, D2W>D2T, and D3W>D3T are satisfied where DiW is a separation between an i-th lens unit and an (i+1)-th lens unit at a wide-angle end, DiT is a separation between an i-th lens unit and an (i+1)-th lens unit at a telephoto end, wherein a diffraction optical element is included in at least one of lens units.

Abstract: A light modulator includes elongated elements arranged parallel to each other and suspended above a substrate. The light modulator operates in a first diffraction mode and in a second diffraction mode. In the first diffraction mode, an incident light diffracts into a single diffraction order. Each of the elongated elements comprises a central blazed portion, a first outer blaze transition, and a second outer blaze transition. The central blaze portion, couples the first outer blaze transition to the second outer blaze transition. Each of the central blazed portions comprises a reflective surface. Selected ones of the central blazed portions comprise a first conductive element. The first outer blaze transition and the second outer blaze transition are coupled to the substrate.

Abstract: The methods and apparatus according to the invention equalize the power of at least one frequency in a multi-wavelength optical signal, or limit the power contained in a single or multi-frequency signal. More particularly, the optical power equalizer according to the invention is a filter with separably variable wavelength dependent transmission coefficients, wherein each coefficient decreases with increasing power for each respective wavelength coupled to the equalizer. Thus, the highest power wavelength output from an EDFA will be filtered more than the lower power wavelengths, making the output power from the EDFA more evenly distributed among the wavelengths. Such an equalizer can be placed downstream from each EDFA without destabilizing the optical network so that no changes need to be made to the EDFA or to the other components in the system.

Abstract: The present invention provides an easily aligned, all-reflective, aberration-free pulse stretcher-compressor in a compact geometry. The stretcher-compressor device is a reflective multi-layer dielectric that can be utilized for high power chirped-pulse amplification material processing applications. A reflective grating element of the device is constructed: 1) to receive a beam for stretching of laser pulses in a beam stretcher beam path and 2) to also receive stretched amplified pulses to be compressed in a compressor beam path through the same (i.e., common) reflective multilayer dielectric diffraction grating. The stretched and compressed pulses are interleaved about the grating element to provide the desired number of passes in each respective beam path in order to achieve the desired results.

Abstract: A diffractive optical element in which eclipse of rays at a grating side surface of a diffraction grating can be reduced is disclosed. In a diffractive optical element comprises a plurality of diffraction gratings made of different materials are laminated, at least one of the plurality of diffraction gratings includes a region in which the grating side surface inclines or a region in which edges thereof are shifted with respect to the edge of another diffraction grating adjacent thereto. The inclination or shift amount is different according to the positions thereof in a surface of the diffractive optical element in accordance with the incident angle or emergent angle of a specified ray such as a ray determined on the basis of an average value, gravity value, maximum value and minimum value obtained from the distribution of incident angle or emergent angle or the like, rays, etc.