439 results about "Blazed grating" patented technology

A multiplexer/demultiplexer is provided for optical interconnection between electronic components on an integrated circuit chip. The multiplexer/demultiplexer includes a substrate formed with an array of photo emitters/detectors and conditioning electronics coupled thereto. A first layer of optically transparent material is formed on the substrate overlying the emitters/detectors and a second layer of optically transparent material, functioning as an optical waveguide, is formed on the first layer. A binary blazed grating is formed at the interface of the two layers. For multiplexing, discrete wavelength optical signals are modulated with data, emitted by the emitters, intercepted by the binary blazed grating, and multiplexed into a polychromatic beam for transmission through the waveguide. For demultiplexing, the discrete wavelengths are separated by the binary blazed grating and directed to corresponding detectors. The conditioning electronics receive and demodulate the output of the detectors to extract data, and format the data for communication with electronic components.

A grating based line narrowing unit for gas discharge lasers with increased beam expansion to produce smaller bandwidths. The grating has a grating surface larger than 100 cm.sup.2 and is a replica grating produced from a master grating produced with a lithography process on a single crystal substrate. In preferred embodiments, a beam from the chamber of the laser is expanded with four prism beam expanders. The large grating, much larger than gratings historically produced from diamond lined gratings, permit substantial reductions in bandwidth while maintaining laser efficiency. A narrow band of wavelengths in the expanded beam is reflected from a grating in a Littrow configuration back via the bi-directional beam expanders into the laser chamber for amplification.

The invention discloses a grating coupler, which sequentially comprises an upper cladding, a grating layer, a wave guide layer and a lower cladding from top to bottom. The grating layer adopts a binary blazed grating that is a one-dimension binary blazed grating or a two-dimension binary blazed grating. The binary blazed grating coupler provided by the invention can obtain high coupling efficiency and realize complete vertical coupling; besides, the preparation is easy. By adjusting a grating parameter, the grating coupler realizes that incident light is respectively coupled in different wave guides according to different polarization states or wave lengths, thus offering effective ways for polarization beam splitting, wavelength division multiplex, etc.

Exposures of a photosensitive material through an array of blazed gratings illuminate a lens asymmetrically to detect effects of a plurality of azimuthal aberrations including coma, astigmatism, and three-leaf and four-leaf clover aberrations. A plurality of such exposures of the array of blazed gratings at slightly differing focus allows detection of focus shift due to any aberrations present in the lens. Upon development of the plurality of exposures, contrast of each area is measured, for example, by reflection or scattering from the relief in the developed photosensitive material and the aberrations thus detected can be simulated by effective summation of individual aberration effects.

The invention provides a detector for detecting total organic carbon (TOC) in sewage, mainly comprising a sample pool capable of being transmitted by ultraviolet rays, a UV optical splitter and a data processor of the organic carbon. The detector is characterized in that UV can emit 240-450nm of UV beams, and a neon lamp is used as a UV light source; the optical splitter is a UV reflective blazed grating, and the light strength of the light beams at each wavelength is detected by a linear array UV CCD (Charged Coupled Device); and the TOC value is determined according to the relationship between the absorbance at the feature wavelength and the TOC content. As known from the scheme, the detector has low cost and good stability and is capable of fully realizing automation and accurately measuring the TOC value so as to comprehensively reflect the pollution degree of the organic matter in the water. Thus, the detector has important help and realistic significance for monitoring and measuring the sewage discharge and the water pollution on the ground surface.

An optical monitoring arrangement utilizes the properties of a blazed Bragg grating to redirect a portion of an optical signal out of the axial path and into a detecting device. A plurality of blazed Bragg gratings are utilized, each having unique properties, to increase the robustness of the monitor. In particular, by utilizing a plurality of N gratings, the bandwidth of the monitor may be increased N-fold (assuming no overlap in wavelength between gratings). Alternatively, an improvement in resolution can be obtained by utilizing a narrower bandwidth and measuring N times the number of raw data points within that bandwidth. A combination of increase in bandwidth and resolution may be obtained by a comprise between these two extremes. Chirped blazed gratings may also be employed.

The invention discloses a high resolution micro infrared spectrometer based on an MEMS scanning micromirror. The high resolution micro infrared spectrometer comprises a fiber connecting device, an incident slit, a collimation reflector, a scanning micromirror, a blazed grating, a spherical surface focusing reflectors, an emitting slit and a high sensitivity unit infrared detector. A novel optical path structure is employed by the high resolution micro infrared spectrometer: an external optical signal to be measured is coupled into a spectrometer through the fiber and the slit and collimated by the spherical surface collimation reflector; the MEMS scanning micromirror and a diffraction grating are utilized to substitute a scanning raster in a traditional scanning raster spectrometer to realize optical splitting and spectrum scanning functions together; during torsional pendulum of the micromirror surface, a combination of two spherical surface reflectors carries out focusing and imaging on the spectrum, so that light with different wavelengths is focused and imaged and irradiates on the detector through the emitting slit successively to realize continuous detection of spectrum. The spectrometer based on the MEMS scanning micromirror provided by the invention has advantages of small volume, wide spectrum measurement scope, high resolution and low cost, etc.

A method is described for determining lens aberrations using a test reticle and a standard metrology tool. The method provides test patterns, preferably in the form of standard overlay metrology test patterns, that include blazed gratings having orientation and pitch selected to sample desired portions of the lens pupil. The method measures relative shifts in the imaged test patterns using standard metrology tools to provide both magnitude and sign of the aberrations. The metrology tools need not be modified if standard test patterns are used, but can be adapted to obtain additional information. The test reticles may be formed with multiple test patterns having a range of orientations and pitch in order to compute any desired order of lens aberration. Alternatively, single test patterns may be used to determine both the magnitude and sign of lower order lens aberrations, such as defocus or coma.

The invention provides a holographic blazed grating manufacturing method. Through making a homogeneous grating on a substrate, taking the homogeneous grating as mask, and carrying out oblique ion beam etching, a needed blazed grating is obtained. Since time of positive ion beam etching can be controlled when making the homogeneous grating, a groove depth of the homogeneous grating is accurately controlled. In addition, after obtaining a photoresist raster through interferometric lithography, ashing technology can be increased further, a duty cycle of the photoresist raster is controlled, and a duty cycle of a needed homogeneous grating is controlled. According to the manufacturing method of the present invention, multi-parameter control of blazed grating manufacture is realized, and manufacture precision is raised.

A detector (110) for determining a position of at least one object is proposed. The detector (110) comprises: —at least one angle dependent optical element (130) adapted to generate at least one light beam (131) having at least one beam profile depending on an angle of incidence of an incident light beam (116) propagating from the object (112) towards the detector (110) and illuminating the angle dependent optical element (130), wherein the angle dependent optical element (130) comprises at least one optical element selected from the group consisting of: at least one optical fiber, in particular at least one multifurcated optical fiber, in particular at least one bifurcated optical fiber; at least one diffractive optical element; at least one angle dependent reflective element, at least one diffractive grating element, in particular a blaze grating element; at least one aperture stop; at least one prism; at least one lens; at least one lens array, in particular at least one microlens array; at least one optical filter; at least one polarization filter; at least one bandpass filter; at least one liquid crystal filter, in particular a liquid crystal tunable filter; at least one short-pass filter; at least one long-pass filter; at least one notch filter; at least one interference filter; at least one transmission grating; at least one nonlinear optical element, in particular one birfringent optical element; —at least two optical sensors (113), wherein each optical sensor (113) has at least one light sensitive area (121), wherein each optical sensor (113) is designed to generate at least one sensor signal in response to an illumination of its respective light-sensitive area by the light beam (131) generated by the angle dependent optical element (130); at least one evaluation device (133) being configured for determining at least one longitudinal coordinate z of the object (112) by evaluating a combined signal Q from the sensor signals.

MEMS magnetometers with optically transduced resonator displacement are described herein. Improved sensitivity, crosstalk reduction, and extended dynamic range may be achieved with devices including a deflectable resonator suspended from the support, a first grating extending from the support and disposed over the resonator, a pair of drive electrodes to drive an alternating current through the resonator, and a second grating in the resonator overlapping the first grating to form a multi-layer grating having apertures that vary dimensionally in response to deflection occurring as the resonator mechanically resonates in a plane parallel to the first grating in the presence of a magnetic field as a function of the Lorentz force resulting from the alternating current. A plurality of such multi-layer gratings may be disposed across a length of the resonator to provide greater dynamic range and/or accommodate fabrication tolerances.

The invention discloses a manufacturing method for a holographic dual-blazed grating. The two blaze angles of the holographic dual-blazed grating are respectively a blaze angle A and a blaze angle B. Different control of the two blaze angles is realized by performing oblique ion beam etching by using a photoresist grating and a homogenous grating as masks on two grating areas A and B, so that a secondary photoresist photoetching process is avoided. When the homogenous grating is manufactured, the positive ion beam etching time can be controlled so that the groove depth of the homogenous grating is controlled precisely. In addition, the homogenous grating mask and the substrate are made of the same material, and the etching rate of the homogenous grating mask and the etching rate of the substrate are kept consistent all the time, so that precise control of the blaze angles can be realized.

The invention discloses a method for producing a holographic double balzed grating, which is characterized in comprising the steps of: (1) coating a photoresist on a substrate of the grating; (2) performing a first interference lithography to produce a photoresist grating mask which is accordant with the requirement of an A balze angle; (3) scanning and etching the grating mask of an A grating area with angled Ar ion beam to be formed into a triangular groove shape of a balzed grating, and washing the substrate; (4) recoating the photoresist; (5) shielding a B grating area, aligning by means of moire pattern with the prepared A grating area, removing the shield, and performing a second interference lithography to produce a photoresist grating mask which is accordant with the requirement of a B balze angle; (6) scanning and etching with the angled Ar ion beam, so that the B grating area is formed into the triangular groove shape of the balzed grating; and (7) washing the substrate to obtain the holographic double balzed grating. The method realizes the production of the holographic double balzed grating, thereby being capable of exactly and respectively controlling the two balze angles.

A bulk micromachined vibratory gyro in which a proof mass has a bulk substrate thickness for a large mass and high inertial sensitivity. In embodiments, optical displacement transduction is with multi-layer sub-wavelength gratings for high sensitivity and low cross-talk with non-optical drive elements. In embodiments, the vibratory gyro includes a plurality of multi-layer sub-wavelength gratings and a plurality of drive electrodes to measure motion of the proof mass induced by drive forces and/or moments and induced by the Coriolis Effect when the gyro experiences a rotation. In embodiments, phase is varied across the plurality gratings and a multi-layer grating having the best performance is selected from the plurality.

The invention discloses a laser radar is based upon lame light source difference absorption process to test thickness of NO2 in the atmosphere, it includes lame light source, light incept and spectrum components, photo-detection and control transaction components, the characteristic is that the light incept and spectrum components accepts the scattered light from atmosphere backward by telescope tube of incept light, after coupling of light fiber, making the light to lay in the focal plane of lens, ripping into the raster by collimation lens, after section out the wave length of light 354.71nm and 360.00nm,recepted by the two emergent light fiber on the focal plane of lens. The raster is blazed grating, it has definite included angle with lens; the photo-detection and control transaction part includes microcomputer, data acquisition card, chronotron, enlarge shaping circuit, photomultiplier and photo-electricity probe. The invention has the beneficial purpose of easy structure, low cost, high diffraction efficiency, good flexibility, convenient using and vindicate etc.

This invention discloses one fiber transmission infrared absorptive firedamp gas test method based on micro split device, which uses wide band infrared light, flash grating, transmission fiber, absorptive chamber, photo electricity detector and signal process circuit, wherein, the light from LED source to get center wave for 1331 nm thin light source through flash grating into incidence fiber transmission and into absorptive chamber full of firedamp gas; the emit light sends through polymer lens coupled to exit fiber then to photo electricity detector and signal process circuit based on gas infrared absorptive rules of Beer-Lambert gas to get gas chamber gas concentration through testing gas chamber infrared attenuate.

The invention discloses a method for producing a convex double blazed grating, which is characterized by comprising the following steps: (1) coating photoresist on a grating substrate; (2) carrying out a first interference lithography to produce a photoresist grating reticle mask corresponding to the requirement of an A blazed angle; (3) forming a triangle blazed grating groove shape by inclining an Ar iron beam to carry out scanning lithography for the grating reticle mask in an A grating area and washing the substrate; (4) coating the photoresist again; (5) shielding a B grating area, utilizing the prepared A grating area to carry out moirefringe alignment, then removing shielding and carrying out a second interference lithography to produce a photoresist grating reticle mask corresponding to the requirement of a B blazed angle; (6) etching the B grating area into a triangle blazed grating groove shape by inclining the Ar iron beam to carry out scanning lithography; and (7) washing the substrate to obtain the convex double blazed grating. The invention realizes the production of the convex double blazed grating and can accurately and respectively control the two blazed angles.

The invention relates to a high-precision roll angle interferometric measuring device based on blazed gratings. The high-precision roll angle interferometric measuring device comprises a dual-frequency laser source, a blazed grating wedge-shaped plate moving along with a measured member, a light interference device and a phase detection device. The dual-frequency laser source outputs an incident light beam comprising two components of different frequencies and orthogonal linear polarization directions to the light interference device, the incident light beam is reflected twice through the blazed grating wedge-shaped plate under the action of the light interference device to form four measuring light beams in spatial parallel, the interference light beams are formed in the light interference device and output to the phase detection device, phase displacement of the measuring light beams is detected by the phase detection device, and a roll angle is determined according to the relationship between the phase displacement and a roll angle of the wedge-shaped plate. The high-precision roll angle interferometric measuring device has the advantages of high anti-interference capability, high measuring accuracy, simple optical structure, few optical component and angle measuring resolution capable of reaching sub-micro radian, and can meet different precision measurement requirements by adopting the gratings of different grating constants.

The invention provides a binary blazed grating coupler. The coupler is made of an SOI material and comprises a silicon substrate, a limiting layer, a waveguide layer and a grating layer. The grating layer is a binary blazed grating, the binary blazed grating is a one-dimensional binary blazed grating or a two-dimensional binary blazed grating, and the binary blazed grating coupler is simple in structure, convenient to manufacture, small in size and compatible with a standard CMOS process and achieves a coupling output function high in coupling efficiency and wide in bandwidth. By bonding a photodetector made of an III-V material to an SOI wafer, a silicon-based mixed integration photodetector with a grating coupling function is achieved; the silicon-based mixed integration photodetector is applied to an array waveguide grating demodulation integration microsystem, and the optical coupling problem between an SOI silicon nanowire waveguide in the array waveguide grating demodulation integration microsystem and an InGaAs/InP photodetector is effectively solved.

The invention relates to a rotary Raman laser radar system based on a grating technology light splitting structure, which comprises a laser emitting system, a receiving system, a light splitting system, a photoelectric detection system and an information processing system, wherein the light splitting system comprises a positive lens, a blaze grating, an optical fiber array, optical fiber couplers and an optical fiber Bragg grating, the optical fiber array and the blaze grating are respectively positioned at the front side and the rear side of the positive lens, a plurality of optical fibers are connected to the optical fiber array, the optical fiber coupler is arranged on each optical fiber and provided with three ports which are respectively PA, PB and PC, and the port PB is connected with the optical fiber Bragg grating. According to the invention, regulation freedom of the rotary Raman laser radar system is reduced; and the rotary Raman laser radar system has the advantages of compact structure, small volume and light weight, and has a certain daytime remote sensing detecting capacity so as to be suitable for vehicle-mounted, air-mounted and satellite-mounted application.

The invention provides a spectrometer which has small volume, simple structure and low cost and uses an MOEMS movable blazed grating array. The spectrometer comprises a light source, a collimating device, a grating or a prism, an imaging device, an MOEMS movable blazed grating array and a driving circuit thereof, and a detector, wherein the collimating device parallels the light beams coming fromthe light source; the grating or the prism receives and disperses the light beams; the imaging device images the dispersed light beams on the MOEMS movable blazed grating array and diffracts the MOEMSmovable blazed grating array to obtain a light beam, and then images the obtained light beam to the detector; the MOEMS movable blazed grating array and the driving circuit thereof are used for diffracting the dispersed light beam; and the MOEMS movable blazed grating array comprises a plurality of parallel MOEMS movable blazed gratings which can be grouped for deflection motion under the controlof the driving circuit so as to gate light beams of different bands. The spectrometer has the advantages of high luminous flux, high light energy utilization rate, high signal-to-noise ratio and thelike, can be widely used in the fields of biochemical analysis, food safety monitoring, etc.