392 results about "Diffraction grating" patented technology

Waveguide combiners with multiple image planes are described herein. In an example, an apparatus includes a first optical element configured to receive light, a substrate having an input surface and an output surface and configured to propagate the light received by the first optical element along a propagation path within the substrate, and a second optical element configured to output the light propagated along the propagation path. The input surface of the substrate is coupled to the first optical element. The second optical element includes a first diffraction grating coupled to the output surface and characterized by a first focal distance and a second diffraction grating coupled to the first diffraction grating in a stacked arrangement and characterized by a second focal distance.

The invention discloses a multi-level diffraction grating precision displacement sensor and a displacement measurement method, and relates to the field of displacement sensors. The grating precision displacement sensor comprises a laser, a half-wave plate, a first non-polarization splitting prism, a + / -2-level diffraction interference grating precision displacement sensor module and a + / -3-level diffraction interference grating precision displacement sensor module. And a final displacement measurement result is calculated after weighting by taking the noise levels of the + / -2-level diffraction interference grating precision displacement sensor module and the + / -3-level diffraction interference grating precision displacement sensor module as weights. The multi-level diffraction grating precision displacement sensor provided by the invention improves the utilization rate of effective light by using the polarization characteristic of light, reduces the interference of environmental stray light on measurement signals, and improves the accuracy and stability of the whole system.

An aberration regulation method of a reflective double-beam interference exposure system, comprising: constructing a reflective double-beam interference exposure system, dividing a light beam output by a laser into two double beams with the same intensity, and forming an interference exposure field; constructing an aberration regulation system, testing and recording the aberration of the double-beam light path by using a spherical interferometer, and regulating the wavefront of any light beam in the double beam by using a deformable mirror, so that the aberration of the light beam matches the aberration of the other light beam, and the regulation of the aberration of the interference exposure field is completed. The present application solves the problems of precise assembly and adjustment, wavefront aberration control and the like of the reflective double-beam interference exposure system based on a large-aperture off-axis parabolic mirror, and provides a new solution for the preparation of a meter-level large-aperture, low-aberration diffraction grating.

An ophthalmic multifocal lens is presented, configured to provide distance vision and at least one other usable visual acuity. The lens comprises a translucent lens body having an optical axis and a refractive baseline, the refractive baseline extending to at least a portion of the lens body, and a diffraction grating configured to act as an optical splitter, extending concentrically in the radial direction and superimposed on at least a portion of the refractive baseline. The diffraction grating configured to act as an optical splitter is further configured to be continuous within at least a central 3 mm aperture, wherein the distance vision is provided by the -1st order diffraction, and the near vision is provided by the 2nd order diffraction.

An optical component (1) comprises a diffraction grating and a microlens array that are hexagonal and angularly offset from each other by 10° to 50°. Such an optical component is particularly well-suited for use in a wavefront analyzer. The wavefront analyzer can alternatively have two configurations, in which the distance between the optical component and an image sensor is close to f / 2 or 3·f / 2, where f is the focal length of the microlenses (11). Such a wavefront analyzer can be compact, easy to use, and compatible with a wide range of wavelength values ​​for the electromagnetic radiation to be analyzed. (Shorthand figure: Figure 1)

A wavelength beam combining device includes: a plurality of laser light sources configured to emit a plurality of laser beams in a first direction and having mutually different peak wavelengths and central axes arranged in a second direction intersecting the first direction; a first diffraction grating disposed at a position where the plurality of laser beams are received, the first diffraction grating being configured to diffract the plurality of laser beams in different directions according to wavelengths of the laser beams to cause the diffracted laser beams to enter the second diffraction grating; a second diffraction grating configured to diffract the plurality of laser beams diffracted by the first diffraction grating to form a wavelength-combined beam, and to direct the wavelength-combined beam in the first direction; and an optical coupling unit configured to couple the wavelength-combined beam to an optical transmission fiber and to be movable in the second direction.

According to the grid line perpendicularity adjusting method and device for the holographic diffraction grating double-beam exposure system, on the basis of the double-beam exposure system, a high-side sag substrate, a cube-corner prism, a rectangular prism, a horizontal adjusting table and a CCD are additionally arranged; a reflection reference surface is established through a cube-corner prism and a right-angle prism, and a to-be-exposed substrate with a high-precision positioning notch is combined, so that high-precision correction of an exposure light path is realized. The method effectively solves the problem that the perpendicularity of the grid line relative to the bottom reference surface of the substrate in double-beam holographic interference photoetching is insufficient, ensures that the prepared grating grid line has high perpendicularity precision, and remarkably improves the diffraction performance of the grating.

The invention provides a hyperspectral imaging system. The hyperspectral imaging system comprises a telescope group, a collimator objective, a prism, a volume holographic diffraction grating, an imaging objective and an imaging sensor which are arranged in sequence, the telescope group is composed of a primary reflector, a secondary reflector, a third reflector, a plane reflector and an entrance slit; the primary reflector, the secondary reflector and the third reflector form an off-axis three-reflector structure; the plane reflector is used for folding a light path; the collimating objective lens, the prism, the volume holographic diffraction grating, the imaging objective lens and the imaging sensor form an imaging spectrometer, and an entrance slit is used as object space input; the formed off-axis three-mirror and folded light path and an imaging spectrometer are in coaxial butt joint by taking an entrance slit as a node, and are used for joint correction and splicing to form a hyperspectral imaging system. According to the optical path architecture, optimal matching of the unobstructed total reflection front end and the transmission type rear end is realized, and the detection sensitivity of crop weak spectrum signals is greatly improved while a better modulation transfer function of a full view field is ensured.

This invention discloses a Littrow-type cavity length-compensated mode-hopping-free continuously tunable semiconductor laser, comprising a laser diode (1), a collimating lens (2), and a diffraction grating (3). Mode-hopping-free continuous tunability is achieved through a micro-elastic material base (4). The micro-elastic material base (4) is hollowed out to create a movable block (401) that can be driven by a piezoelectric ceramic (5), an isosceles triangular groove (404), and a pair of waist arms (406), enabling micro-displacement and micro-angle changes in the waist arms (406), thereby achieving continuous tunability of the output laser. This invention achieves mode-hopping-free continuous tunability of the laser output through an innovative combination of a special mechanical structure and the frequency selection characteristics of the grating. The structure is compact and highly stable, ultimately resulting in a mode-hopping-free continuously tunable external cavity semiconductor laser that meets the requirements of high-end precision measurement.

The application discloses a motor assembly, a camera module, an electronic device, a position detection method and device. The motor assembly comprises a first shell, a photosensitive chip arranged in the first shell, the photosensitive chip being capable of moving relative to the first shell, the photosensitive chip being provided with an imaging area, a position detection member arranged in the first shell, the position detection member comprising a second shell connected with the first shell, the second shell being provided with a light transmission part, a light emitter arranged in the second shell, the light emitter being provided with an emitting port, a diffraction grating arranged in the second shell, the diffraction grating being located between the emitting port and the light transmission part, and a pixel unit group arranged in the photosensitive chip, the pixel unit group comprising a first pixel unit and a second pixel unit, the first pixel unit being provided with a plurality of arrayed first light transmission ports, the second pixel unit being provided with a plurality of arrayed second light transmission ports, and the width of the first light transmission port being smaller than the width of the second light transmission port.

A method includes acquiring and characterizing multiple laser beams. The method includes tracking the acquired laser beams. The method includes controlling a beam of the acquired laser beams. The method includes implementing an adaptive learning detection algorithm to identify and track a unique optical signature from at least one of the acquired laser beams. The method includes steering at least one laser beam towards a target based on the acquired laser beams. The method includes changing one or more optical properties of a beam steering unit to steer the at least one laser beam towards the target, including one or more of the following: inducing a Pockels effect on the at least one beam by applying an electric field; tuning Spatial Light Modulators; tuning a metamaterial structure; inducing a diffraction grating; and modifying an output angle of the at least one beam.

There was a need for optical components or elements that would be useful in miniaturizing spectroscopic devices. [Solution] An optical component made of a solid material that transmits light of a wavelength to be used, characterized in that a diffraction grating consisting of a plurality of grooves extending along a second direction is provided on a first optical surface into which the light of the wavelength to be used is incident, and a plurality of lenses arranged along the second direction are provided on a second optical surface into which the light of the wavelength to be used that was incident from the first optical surface is emitted.

Output diffraction gratings, diffractive waveguide combiners, and augmented reality or virtual reality displays are disclosed. An output diffraction grating includes a first array of optical structures arranged on a plane and forming a two-dimensional grid, the first array including first adjacent optical structures spaced apart from one another in each of a first direction and a second direction in the plane of the output diffraction grating such that they are not in contact with one another, and a second array of optical structures arranged on the plane and forming a second two-dimensional grid, the second array including second adjacent optical structures similarly spaced apart from one another such that they are not in contact with one another; the first array is superimposed on the second array such that the first and second arrays are spatially offset from one another in the first and second directions and are not in contact, and an optical structure from the second array is disposed between one of the first adjacent optical structures; each of the optical structures in the first array includes a different shape in the plane from each of the optical structures in the second array.

The invention relates to a naked-eye 3D display system based on a multi-layer phase modulation composite grating, belongs to the technical field of stereoscopic display, and aims to overcome the technical bottlenecks of low brightness of an existing parallax barrier grating, large crosstalk caused by large thickness of a cylindrical lens and serious dispersion of a diffraction element. The system comprises a two-dimensional display panel and a composite diffraction grating, pixel units of the display panel are composed of red, green and blue sub-pixel matrixes and are coded according to viewpoints. The composite diffraction grating is attached to the light emitting side of the panel, is made of an optical anisotropic material and is of a multi-layer structure, and a first micro-nano structure layer and a second micro-nano structure layer are sequentially arranged along a light path; the first layer is an aspherical focusing array, and the phase delay of the aspherical focusing array meets a quadric surface function so as to collimate light waves; the second layer is a dispersion compensation type deflection array, and the grating period of the second layer is accurately matched with the central wavelength of the sub-pixels, so that light of different colors is projected at the same deflection angle. According to the invention, full-color dispersion-free display is realized, the thickness of the device is less than 50 microns, and crosstalk is obviously reduced.

The method may include the step of receiving time-varying interference signals from two or more photodetectors associated with a grating structure and a reference grating structure. The grating structure may include one or more diffraction gratings, the reference grating structure may include a reference grating positioned next to one or more diffraction gratings of the grating structure, and one or more illumination beams may interact simultaneously with the grating structure and the reference grating structure as the sample is scanned with respect to the illumination beams. The method may include the step of determining at least one of the real-time position or scanning speed of the grating structure during scanning based on the reference grating signal. The method may also include the step of determining one or more overlay errors based on the grating signal from the grating structure during scanning and the real-time position of the grating structure, which are determined based on the reference grating signal.

It is an object of the present invention to provide a semiconductor laser having excellent high output characteristics and wavelength uniformity.SOLUTION: A semiconductor laser according to a first aspect of the present application includes a substrate, an active layer, a cladding layer including a first diffraction grating layer having a first diffraction grating structure and a second diffraction grating layer having a second diffraction grating structure, and an electrode. The active layer and the cladding layer constitute a mesa structure, and have a first reflection region and a second reflection region constituting a resonator in a direction in which the mesa structure extends. A second diffraction grating structure is formed in the first reflection region, and one of the first diffraction grating structure and the second diffraction grating structure is formed in the second reflection region. The first diffraction grating structure and the second diffraction grating structure are formed such that a normalized coupling coefficient of the first reflection region is larger than a normalized coupling coefficient of the second reflection region. The mesa structures of the first reflection region and the second reflection region have different mesa widths depending on the refractive index.SELECTED DRAWING: Figure 2

A display may use a waveguide to provide image light to an eye box. An emitter may emit infrared light collimated at different angles relative to a collimated axis and divergent along an orthogonal axis. The waveguide may propagate the infrared light and may include overlapping one-dimensional diffractive gratings with parallel periodic structures. Each grating may diffract, towards the eye box, a respective portion of the infrared light from a respective incident angle onto a respective output angle relative to the collimated axis. A camera may capture glints of the infrared light as reflected off a user's eye at the eye box for performing gaze tracking. The emitter and the gratings may effectively form a one-dimensional line of infrared emitters overlapping the eye box while allowing the optical emitter to remain invisible to a user.

An apparatus includes a first light waveguide including: a first in-coupling diffraction grating to in-couple first input beams of light into the first light waveguide from a first light engine, a first expander to expand the first input beams of light to form first expanded beams of light, a first out-coupling diffraction grating to out-couple the first expanded beams of light; and a second light waveguide including: a second in-coupling diffraction grating to in-couple second input beams of light into the second light waveguide from a second light engine, a second expander to expand the second input beams of light to form second expanded beams of light, and a second out-coupling diffraction grating to out-couple the second expanded beams of light. The first light waveguide provides a first image, and the second light waveguide provides a second image.

The invention provides a graphical baffle plate, a depth control method of a micro-nano optical structure and a diffraction grating, the graphical baffle plate is used for modulating the micro-nano optical structure with continuous and gradually changing depth, the baffle plate comprises a fan-shaped substrate I and a fan-shaped substrate II, the circle center of the fan-shaped substrate I and the circle center of the fan-shaped substrate II coincide, and the edges of the fan-shaped substrate I and the fan-shaped substrate II are arranged adjacently; the fan-shaped base plate I is composed of at least one fan-shaped section; the fan-shaped substrate II is formed by concentrically and adjacently combining at least two fan-shaped sections with different radiuses; the radius of any fan-shaped section in the first fan-shaped base plate is not equal to that of any fan-shaped section in the second fan-shaped base plate. By setting different radiuses of different fan-shaped sections, the etching precision of the nanoscale optical structure is improved, and particularly, accurate modulation of continuous gradual change of depth is realized, so that a plurality of grating structure regions with different depths are prepared, and the grating structure depths in the grating structure regions are the same.

An elastic modulus of a viscoelastic body can be calculated with a high spatial resolution and in a relatively short measurement time. A projection image of an X-ray is detected with a detection unit by vibrating an object while maintaining a relative positional relationship between a first diffraction grating and a second diffraction grating. Then, an elastic modulus of the object is calculated based on a displacement amount of a wave due to the vibration in the projection image of the X-ray detected by the detection unit.

The invention relates to a quantum cascade laser emitting a polarized TM optical mode with a wavelength between 3 and 15 µm, comprising an amplifying medium and a main waveguide. The latter includes a coupling section in contact with the amplifying medium, comprising a diffraction grating (DFB). The coupling section has a width greater than or equal to a minimum width from which an antisymmetric supermode propagating in a laser guidance structure comprising the amplifying medium and the main waveguide has a confinement factor in an active region of the amplifying medium strictly greater than those of the optical modes capable of being guided by the guidance structure. The main waveguide comprises a core based on atoms from column IVA of the periodic table of elements and a confinement subshell of SiN or a chalcogenide. (See Figure 1A for the abstract.)

According to one embodiment, a display structure comprises: a waveguide (101); a coupling-in structure (102) on a first side (110) of the waveguide (101), comprising a diffraction grating feature and a sub-wavelength grating feature, and configured to receive light (104) comprising a first polarization and a second polarization, where the diffraction grating feature is configured to couple at least a portion of the first polarization to the waveguide as coupled-in light (105), and where the sub-wavelength grating feature is configured to couple at least a portion of the second polarization to the waveguide as coupled-in light (105). The sub-wavelength grating feature is configured such that the diffraction grating feature is at least partially transparent to the second polarization; and a polarization steering grating (103) on the second side (111) of the waveguide (101) configured to receive at least a portion of the coupled light (105) and to rotate the polarization of the coupled light (105), generating polarization-rotated coupled light (106) when the coupled light (105) is reflected back from the second side (111) of the waveguide (101) back to the first side (110) of the waveguide (101).

A spectrometric device according to an aspect of the present application includes: a light splitting section (2) including a diffraction grating; a detection section (2) that detects light wavelength-dispersed by the diffraction grating; a rotation section that rotates the diffraction grating; a light blocking section that blocks measured light introduced into the light splitting section; a measurement condition setting section (4, 5) that sets a plurality of measurement conditions including a wavelength of a measurement target and at least one parameter value among an integration time, a gain, or a number of data accumulations; and a control section (4) that acquires a dark field measurement value for each of the plurality of measurement conditions set by the measurement condition setting section, blocks the measured light using the light blocking section, and performs a dark field measurement at other parameter values included in each measurement condition after rotating the diffraction grating to a position corresponding to the measurement target wavelength included in the measurement condition using the rotation section. Thus, a dark field measurement value can be accurately obtained.

A diffraction grating coupler (10) is provided with: a diffraction grating (12) having a plate-shaped base material (121) and different refractive index regions (122) that are periodically arranged in a one-dimensional or two-dimensional manner within a predetermined range of the base material (121) and have a refractive index different from that of the base material (121); and a light reflecting section (14) provided at an end of the range on the opposite side from the light input section (13) side, the different refractive index region (122) having a planar shape in which the absolute value of the direct coupling coefficient (kappa 1D) is less than 1 / L, the direct coupling coefficient (kappa 1D) is an index indicating the intensity of light traveling from the light input unit (13) in a first direction (positive x-direction) parallel to the base material (121) reflected in the different refractive index region (122) in a second direction (negative x-direction) that differs by 180 DEG from the first direction (positive x-direction) without any radiation loss. The 1 / L is the reciprocal of the span length (L) of the range in relation to the first direction (positive x direction), and the light input portion (13) is a part of the end portion of the range.

An optical component has an optical functional layer with variable light transmittance disposed between multiple light guide plates. The optical functional layer has a main surface provided with a light-receiving section that receives a control light that causes the light transmittance of the optical functional layer to change, and an end surface provided with a light leakage prevention section that reflects the control light. The light-receiving section includes a transmission type diffraction grating. A non-transmissive section that absorbs or reflects the control light is provided between the light guide plates in a path of a zero-order light of the control light transmitted through the transmission type diffraction grating. With this structure, an optical component and a light control device can be provided in which deterioration of the non-transmissive section is prevented and the control light is not visible from either the control light irradiation side or the opposite side.

An diffraction grating comprises: a substrate; and a plurality of micro-structure units, which are formed on the substrate and are periodically arranged at intervals in a first dimension direction (p1) and a second dimension direction (p2). A pattern formed by the orthographic projections of the micro-structure units on the substrate comprises a first closed pattern, wherein the first closed pattern is an asymmetric pattern, the boundary of the first closed pattern is formed by sequentially connecting three or more edges in a surrounding manner, and among the three or more edges, there is at least one straight-line edge, which is neither parallel to the first dimension direction (p1) nor to the second dimension direction (p2).

The invention relates to a lighting device (1) for a motor-vehicle part, comprising an optical film (100) comprising a body (110) extending in a main extension plane and configured to propagate a plurality of light beams (F1), the optical film comprising a first series (S1) of multiple diffraction gratings called light entry diffraction gratings (120), arranged in a first direction in the main extension plane of the body (110), each light entry grating of the first series being intended to face a light source and each light entry grating of the first series comprising multiple periodic, inclined optical patterns (121) configured to make a light beam generated by the light source propagate through the body (110) in a second direction in the main extension plane of the body (110), the second direction being different from the first direction. The invention also relates to a vehicle part (3) comprising the lighting device.

To achieve high spectral performance [Solution] The infrared spectrometer according to the embodiment comprises a diffraction grating structure, a metal thin film, and a current detection unit. The diffraction grating structure includes continuous convex and concave portions. A metal thin film is formed on the surface of the diffraction grating structure so that surface plasmon resonance can be excited when infrared light is incident at a specific incident angle. The current detection unit detects the current generated by the surface plasmon resonance. The pitch of the uneven structure in the diffraction grating structure is 1.52 times or more and 2.17 times or less the width of the convex portion.

The invention relates to the technical field of laser, in particular to a compact spectrum beam combining device which comprises a laser unit, a reflection type conversion mirror, a reflection type diffraction grating, a light path compression assembly and an outer cavity mirror. The optical path compression assembly comprises at least one waveguide structure; in a light path in the spectral beam combining direction, the laser units are distributed on the two sides of an optical axis, and the reflective diffraction grating and the external cavity mirror are both arranged at the optical axis. In a light path in the non-spectral beam combination direction, the position of the laser unit coincides with the position of the reflective diffraction grating; an inclined angle delta theta is formed between the reflective diffraction grating and the optical axis, and the inclined angle delta theta does not exceed 5 degrees; by introducing the optical path compression assembly, the reflection type conversion lens and the reflection type diffraction grating, multiplexing reflection and diffraction are achieved, light passes through the optical path compression assembly four times, the physical size of the whole spectrum beam combining structure is greatly reduced under the condition that the optical path is not changed, and a technical approach is provided for achieving a compact, high-power and high-beam-quality laser.

An optical device and to a corresponding manufacturing process, the device including a textured layer including, on its surface, first macro-textures; and a carrier including, on its surface, a holographic layer intermediate between the textured layer and the carrier. The holographic layer includes a diffraction grating forming, via a holographic effect, an arrangement of pixels in a basis of at least two distinct colours. The textured layer is assembled by lamination with the carrier so that the holographic layer, placed between the textured layer and the carrier, is deformed by the first macro-textures so as to include second macro-textures conformal with the first macro-textures, the visual appearance of the arrangement of pixels being personalized via the second macro-textures.