2038 results about "Lens array" patented technology

The invention provides a seed packaging bag AI intelligent anti-fake traceability management system and method, and relates to the field of household kitchens. The AI intelligent anti-fake traceability management system for the seed packaging bag comprises an intelligent anti-fake packaging bag which is provided with a natural random physical texture layer, a dynamic optical structure layer covering the natural random physical texture layer and an encrypted identifier storing a digital identity (DID), and the microstructure of the natural random physical texture layer forms a uniqueness feature which cannot be copied. The dynamic optical structure layer generates a variable optical effect during physical interaction. Unique biological fingerprints are formed through microcosmic random textures of a packaging base material, the optical variable effect of a microlens array is overlaid, each packaging bag has the unclonability of the physical level, and in combination with dynamic comparison of a multi-mode AI engine on real-time texture features and block chain anchoring initial values and optical living body frequency analysis, the non-clonability of the packaging bag is improved. And a three-dimensional verification closed loop which is difficult to break by a counterfeiter is realized.

The invention discloses a medium-wave infrared pixel-level spectral polarization optical system, which belongs to the field of lenses and comprises a refraction lens group, a cold diaphragm, a super-structure micro-lens array and a medium-wave infrared quantum dot detector which are sequentially arranged along an incident light path, the super-structure micro-lens array comprises an object side micro-structure and an image side micro-structure; the image side microstructure is used for realizing focusing; the object side microstructure comprises a plurality of object side units which are periodically distributed; each object side unit comprises a polarization metal wire grating structure and a plurality of metasurface-microcavity structures; the polarization metal wire grating structure is formed by arranging metal wire gratings according to different directions so as to realize detection of different orthogonal polarization states; the metasurface-microcavity structure comprises a middle dielectric layer, distributed Bragg gratings located on the two sides of the middle dielectric layer and a metasurface columnar structure unit array embedded into the middle dielectric layer, and the metasurface columnar structure unit array is used for achieving filtering of light of different wave bands. The system has the advantages of good imaging quality, small size, real-time imaging and the like.

The invention relates to the technical field of image processing, in particular to a real-time exposure control and image synthesis method for a multi-lens array, which comprises the following steps: an acquisition step: acquiring images shot by a plurality of lenses and corresponding sensor read-out rate information; a processing step comprising: determining exposure parameters through a multi-level hardware level exposure control unit based on the image and the sensor readout rate information; adjusting exposure settings of the plurality of lenses according to the exposure parameters; generating a mask based on the adjusted images shot by the plurality of lenses; performing image synthesis according to the mask and the images shot by the plurality of lenses; the output step comprises the step of outputting the synthesized image, the method can complete exposure parameter adjustment of a plurality of lenses within the millisecond level, and the real-time performance of the system is greatly improved. Meanwhile, an exposure prediction mechanism based on reinforcement learning enables the system to quickly adapt to scene changes, and the problem of response lag of a traditional method is effectively solved.

The invention discloses a method for improving the heat dissipation performance of an AlGaInP red light Micro LED chip. The method comprises the following steps: S1, preparing an epitaxial structure: processing a substrate and a buffer layer, growing an etching barrier layer and an ohmic contact layer, and carrying out stacking epitaxy on a functional layer; s2, patterning the silicon-based substrate: preparing a dielectric layer and a metal structure; s3, diamond ohmic contact layer integration: processing a p-type conductive diamond film layer, and carrying out metal reflection and bonding; s4, removing the substrate and forming an n-type structure: stripping the substrate to be in n-type contact; s5, back-end process integration: preparing an electrode and an optical structure; according to the invention, the heat dissipation performance of the chip is significantly improved; the series resistance is reduced by 30%-50%; the resistivity of the p / n type diamond ohmic contact layer is reduced by 1-2 orders of magnitude compared with ITO; gaAs material light absorption and metal shading are avoided, and the red light transmittance is improved from 75% to more than 90% by combining with the micro lens array; the method is compatible with existing MOCVD, CVD and photoetching processes, large-scale production of wafers of 2-12 inches can be achieved, and the manufacturing cost is reduced.

The invention relates to the technical field of optical nondestructive testing equipment for the sealing performance of a blueberry bottle opening, in particular to an optical nondestructive testing device and method for the sealing performance of the blueberry bottle opening. According to the technical scheme, the optical nondestructive testing device for the sealing performance of the blueberry bottle opening comprises an optical testing device, mounting grooves, a lead screw, a mounting support, a mounting ring, a Fresnel lens, a micrometer caliper, a double-color laser line light source and a rotating motor, and the mounting grooves are formed in the two sides of the interior of the optical testing device; compared with a traditional optical nondestructive testing device for the sealing performance of the blueberry bottle opening, a single light source or a simple lens group is mostly adopted, a 360-degree annular area of the bottle opening is difficult to cover, illumination on the edge of the bottle opening or a complex curved surface area is insufficient, and tiny defects are prone to being omitted; according to the optical nondestructive testing device for the sealing performance of the blueberry bottle opening, the double-color laser line light source is matched with the Fresnel lens array, multispectral reflection data are synchronously collected, the surface micro-mark contrast is enhanced by utilizing wavelength difference, and the monochromatic light detection sensitivity is effectively improved.

An optical speckle receiver for receiving a speckle signal from a sample, the optical speckle receiver comprising an optical detector and an aperture and / or lens array. The aperture and array respectively comprise a plurality of apertures or lenses and is located between the sample and the optical detector such that the received speckle pattern is obtained from multiple discrete sample locations.

The invention relates to the field of spectral imaging, in particular to a double-step Fabry-Perot interference snapshot imaging spectrometer, which comprises a telescopic system, a micro lens array, a Fabry-Perot array interference system and an area array detector, and is characterized in that the telescopic system is used for collecting a target light field and carrying out view field limitation and collimation on the target light field; the Fabry-Perot array interference system is used for modulating a target light field into an interference light field array, the Fabry-Perot array interference system comprises two step lenses which are orthogonal in the step direction, the highest steps of the two step lenses are tightly attached, and an air gap with the thickness changing in a checkerboard-shaped two-dimensional increasing mode is formed between the two step lenses; the microlens array is used for imaging the interference light field array onto the area array detector through each imaging channel; and the area array detector is used for receiving the transmission image field of the microlens array to obtain an interference image array. The invention has the advantages of small volume, light weight, compact structure, static state, stability, reliability and the like.

The invention discloses a peripheral visual area defocused long-distance imaging optical system, and the system comprises a defocus panel which is located right above an observed object, and comprises a flat plate region and a micro-lens array region; the flat plate area is used for directly transmitting light emitted by an observed object; the micro-lens array area is used for carrying out first imaging on the peripheral area of an observed object to form a real image; the objective lens is positioned right above the defocus panel, and is used for performing first imaging on the observed object to form a virtual image of the observed object, receiving a real image of a peripheral area of the observed object, and performing second imaging to form a virtual image of the peripheral area of the observed object; the eyepiece is located right in front of the human eyes and used for conducting secondary imaging on the observed object, forming an amplified long-distance virtual image in front of the human eyes, receiving a virtual image of the peripheral area of the observed object and forming a real image in front of the peripheral retina in the human eyes. And the purpose of preventing and controlling myopia is better achieved.

The invention is suitable for the field of imaging, and discloses a micro lens array zoom module zoom method and an imaging system, and the method comprises the steps: obtaining a mapping relation table between a deviation objective lens working distance and a micro lens array state of a micro lens array zoom module; acquiring a laser spot image formed by irradiating the to-be-measured object with laser, and calculating the position of the to-be-measured object to the focal plane of the objective lens; determining an adjustment reference distance of the micro-lens array zoom module based on the position from the object to be measured to the focal plane of the objective lens, and comparing the adjustment reference distance with the mapping relation table to determine the micro-lens array state of the micro-lens array zoom module; and on the basis of the determined state of the microlens array, a focusing instruction is generated so as to realize automatic zooming of the microlens array zooming module, automatic zooming of the microlens array zooming module is realized, and the method has the advantages of extremely high focusing speed and high precision.

The utility model discloses a micro-fluidic chip imaging positioning device, and belongs to the technical field of micro-fluidic chip positioning. According to the technical scheme, the system comprises a microcosmic illumination module, a microcosmic imaging module, a chip moving and macroscopic illumination module, a macroscopic imaging module and an optical path multiplexing module; the microscopic illumination module comprises a fly's-eye lens assembly, the fly's-eye lens assembly comprises two fly's-eye lenses, the optical axes of the two fly's-eye lenses are parallel to each other, and the focus of each lens array element in one fly's-eye lens coincides with the center of the lens array element at the corresponding position of the other fly's-eye lens. The micro-fluidic chip clamp is applied to the aspect of micro-fluidic chip imaging positioning, overcomes the defects caused by an existing micro-fluidic chip clamp, solves the technical problems of universality, automation and high precision of micro-fluidic chip positioning, and has the characteristics of rapidness, automation, high precision and universality.

The invention provides a low-chromatic-aberration transparent display device in order to solve the problem that chromatic aberration easily occurs in polarization modulation stereoscopic display adopting a 1 / 4 wave plate. The low-color-difference transparent display device comprises a directional polarization light source, a reflector and a transparent liquid crystal display panel. The pixels on the upper portion of the 2D display panel are lightened in a time-division multiplexing mode and any time slice slot, light rays of the pixels are projected through the lens array and then reflected through the reflector, the polarization direction of the light rays is adjusted, and then the light rays penetrate through the transparent liquid crystal display panel to form viewpoints. The transparent liquid crystal display panel synchronously provides a parallax image corresponding to the viewpoint position. The sub-pixel value of any one lightened pixel on the 2D display panel is modulated to be a fixed value related to the included angle of the lens, so that colored light generated by the pixel is restored to be white light after being polarized by the polarizer, the polarization direction is adjusted by the 1 / 4 wave plate and the polarization of the analyzer. At the moment, a directional light source without chromatic aberration is provided for the transparent liquid crystal display panel, so that chromatic aberration introduced by the polaroid and the wave plate is reduced.

The invention discloses a micron-sized lens array machining device and method based on a micro-forming tool, and relates to the technical field of micron-sized lens array machining, the micron-sized lens array machining device comprises an ultra-precision machine tool with a Y axis, a lifting tool rest and an arc tool, a vacuum chuck on the Y axis of the ultra-precision machine tool is used for installing a workpiece, and the lifting tool rest is used for installing the arc tool; the lifting tool rest can drive the arc tool to ascend and descend in the Y direction and enable the arc tool to machine the surface of a workpiece to form a micro-lens unit, and the ultra-precision machine tool can drive the workpiece to move in the X direction, the Y direction and the Z direction relative to the arc tool and enable the arc tool to machine the surface of the workpiece to form a micro-lens array. And the radius of a cutting edge of the arc cutter is equal to the curvature radius of the micro-lens unit. According to the invention, high-quality and high-uniformity micron-sized lens array processing can be realized.

The invention discloses a photoresist micro-lens array preparation method and system, and relates to the field of micro-nano optical device manufacturing. The preparation method of the photoresist micro-lens array comprises the following steps: carrying out chemical mechanical polishing treatment on a silicon wafer, spin-coating photoresist on a substrate to form a cylindrical array, and eliminating solvent gradient through pre-drying; forming a fluorocarbon nano film on the surface of the photoresist through plasma deposition so as to reduce the surface energy of the photoresist; realizing hot reflux of the photoresist based on gradient annealing, wherein the gradient annealing comprises a preheating section, a main reflux section and a stable section; on the basis of the preheating section, glass transition stress is avoided, fluorine-containing gas and inert gas are synchronously introduced into the main backflow section to act on a plasma sheath layer, so that the flowing direction of photoresist is regulated and controlled, and the edge coffee ring effect is inhibited; the stable section synchronously performs plasma assistance to lock the shape; and the precision and the consistency of the micro-lens array are improved through segmented temperature regulation and control and a plasma auxiliary technology.

The invention provides an optical cross system based on silicon-based liquid crystal and a control method, and relates to the field of optical elements, and the optical cross system comprises an optical fiber array, a micro lens array, a collimating lens, a polarization conversion module, a dispersion element, a focus lens group and a liquid crystal spatial light modulator. Optical signals are coupled through the micro-lens array, a divergence angle is compressed, and parallel light beams are formed through the double-agglutination collimating lens; the polarization conversion module separates the light beam into P / S polarized light and unifies the polarization state; the dispersion element separates light beams according to wavelength space, and the focus lens group forms an elliptical Gaussian light spot on the liquid crystal spatial light modulator; the liquid crystal spatial light modulator divides a light spot into a plurality of independent control areas in the long-axis direction, and single-wavelength multi-port output, power proportion regulation and control and monitoring signal extraction are achieved by dynamically modulating the reflection phase of each area. The control method comprises the steps of optical path processing, regionalized phase modulation and real-time monitoring feedback. According to the invention, flexible routing, power balance and lossless monitoring of wavelength channels can be realized.

An image sensor may include pixel groups arranged in a Bayer pattern and a color separating lens array that separates incident light by wavelengths and concentrates the separated incident light on the pixels. The color separating lens array may include pixel corresponding groups, with each group having regions containing nanoposts in two layers. In each of the pixel corresponding groups in each of the two layers, there are a central group and a plurality of peripheral groups. The displacements of arrangement centers of the nanoposts in at least two of the peripheral groups have variations.

To provide an optical unit which is used inside of a laser oscillator of an external resonance type and capable of suppressing an output loss during external oscillation.SOLUTION: An optical unit 60 comprises a FAC lens array 63 and a beam twister array 64. A second surface 63b of the FAC lens array 63 includes a curvature part. A first surface 63a of the FAC lens array 63 and third and fourth surfaces 64a and 64b of the beam twister array 64 are flat surfaces. A first antireflection layer AR1 of a first reflection factor is provided on the flat surface, and a second antireflection layer AR2 of a second reflection factor is provided on the second surface 63b. The first and second reflection factors are lower than a predetermined reflection factor, and the second reflection factor is higher than the first reflection factor. A fluctuation rate of the reflection factor with respect to film thickness fluctuation of the second antireflection layer AR2 is smaller than that of the first antireflection layer AR1.SELECTED DRAWING: Figure 7B

The invention belongs to the technical field of gas detection, and particularly relates to a multi-component gas detection device and a detection method.The multi-component gas detection device is characterized in that according to components of detected gas, a laser driver drives a laser array to emit light with different modulation frequencies and multiple wavelengths, the light is changed into parallel light after passing through an optical fiber array and a micro-lens array, and the parallel light is transmitted to a gas detector; after gas to be detected is absorbed and reflected by a diffuse reflection surface, reflected light passes through a lens and a dichroscope to be converged, light with long wavelength and light with short wavelength respectively enter photoelectric detectors with corresponding wave bands, the photoelectric detectors convert optical signals into electric signals and filter the electric signals, and the filtered signals to be detected are transmitted into a digital lock-in amplifier to be processed in parallel. And demodulating second harmonics and first harmonics of different gases, and calculating the concentration of each to-be-detected gas through a calculation unit. According to the invention, simultaneous detection of multi-component gas concentration can be realized.

The invention discloses a method for preparing a small numerical aperture microlens array, which comprises the following steps of: preparing a silicon-based surface adhesive layer, exposing and overlay, developing, hot melting, etching and the like, setting photoresist spin-coating to be multi-layer spin-coating, enabling photoresist materials and spin-coating parameters of different adhesive layers to be different, enabling the viscosities of three layers of photoresist to be obviously distinguished, and improving the resolution of the three layers of photoresist. The factor is a key factor for influencing subsequent small numerical aperture microlens forming; circular masks with different areas are designed, precise control on the aperture of the micro lens after hot melting of the lens can be realized after overlay exposure, and the surface uniformity of the micro lens array in the silicon-based wafer is improved; the temperature and time of hot melting and baking are the key of fusing the double-layer photoresist structure to form the micro lens; the etching parameters with the etching speed higher than that of silicon are selected, the curvature radius of the microlens can be further increased, the small numerical aperture and the size of the microlens are reduced, and therefore preparation of the small numerical aperture microlens array is effectively achieved.

Lens arrays of an image reading device in which lens bodies are arranged in a main scanning direction are connected with a gap therebetween. A plurality of first slit portions and a plurality of second slit portions are provided along the main scanning direction between the lens arrays and an image sensor. The first slit portion includes first light shielding plates that separate optical paths of light passed through the lens bodies. The second slit portion includes the first light shielding plates and a second light shielding plate that restricts an optical path of light passed through a lens body closest to the gap at a gap side. The position of the second light shielding plate in a direction along the optical path at the image sensor side is closer to the lens arrays than the first light shielding plates are.

The invention discloses a high-precision multi-layer sliding shaft clamp based on a wedge-shaped guide rail structure, and relates to the field of micro-lens array manufacturing and other ultra-precision machining. The problem that in the ultra-precision machining process, when a machine tool is not provided with a guide rail in the vertical direction, centering cannot be efficiently achieved is solved, and the problems that in a traditional centering mode, operation is tedious, the installation and adjustment time is long, the production cost is high, and the machining efficiency is low are solved. A second-stage bottom plate relatively sliding in the ascending direction is arranged above a first-stage bottom plate, and a servo motor transmits power to a transmission mechanism to achieve horizontal linear motion of the second-stage bottom plate relative to the first-stage bottom plate; a third-level bottom plate which relatively slides in the ascending direction is arranged above the second-level bottom plate, a main shaft holding clamp which relatively slides in the direction perpendicular to the ascending direction is arranged above the third-level bottom plate, and the first-level bottom plate and the second-level bottom plate, the second-level bottom plate and the third-level bottom plate and the third-level bottom plate and the main shaft holding clamp are detachably connected through locking pieces. The device is used for achieving vertical centering work of the machine tool spindle.

Disclosed in the present invention are a multispectral light field imaging system, and a three-dimensional temperature field measurement method and measurement system. The multispectral light field imaging system comprises: a primary lens, a micro-lens array, a first relay lens, a dichroic mirror, a second relay lens, a third relay lens, a first image sensor, a first optical filter, a second image sensor and a second optical filter, wherein the micro-lens array is located at an image plane of the primary lens; the first relay lens, the second relay lens and the third relay lens together form a 1:1 relay lens group imaging system on an optical path of a spectral band I and an optical path of a spectral band II; an angle of 45° is formed between the dichroic mirror and an optical axis; and the first image sensor is located at a focal plane of the second relay lens, and the second image sensor is located at a focal plane of the third relay lens. The present invention realizes the collection of multispectral light field data while maintaining the amount of light field data of each spectrum unchanged, such that an instantaneous three-dimensional temperature field of a flow field can be measured.

The invention provides a near-eye light field display method, system and device, a medium and a program product. The method comprises the following steps: determining a target lens in a lens array according to the sight line direction of a target object; based on the sight line direction of the target object and the target lens, simulation light is determined, and the simulation light is consistent with the sight line direction, penetrates through the target lens and then is projected to the display device; determining a target area of the display device based on the intersection point of the simulation light and the display device; and displaying an image watched by the target object in the target area. According to the method, the matching degree between the image displayed by the near-eye light field display equipment and the visual field of the user is improved, and the fidelity of the image watched by the target object can be improved.

The invention relates to the field of light field imaging, in particular to a light field camera calibration method based on original light field image line feature detection, which comprises the following steps: acquiring a white background original light field image set of a light field camera under different shooting conditions, and processing to obtain projection center grid data of a microlens array; obtaining a checkerboard original light field image set of the light field camera under different shooting conditions, and loading projection center grid data of the micro-lens array on each checkerboard original light field image; calculating a gradient value of each pixel in each checkerboard original light field image, queuing the gradient values of the pixels, and performing region diffusion and model fitting according to a gradient angle similar direction to obtain line features in each checkerboard original light field image so as to calculate angular point coordinates of each checkerboard original light field image; and constructing a light field camera projection model, and calibrating parameters of the light field camera in combination with the angular point coordinates. According to the method, introduced errors are reduced while time is saved.

The invention relates to the technical field of target distance detection and 3D scanning reconstruction, and discloses a coaxial scanning type ultra-long distance detection laser radar system, which comprises a laser light source module, which adopts a 1550nm optical fiber laser to output high-power laser, and ensures sufficient laser energy and human eye safety; according to the invention, by adopting the high-power 1550nm fiber laser, the ultra-long distance detection is realized on the premise of ensuring the safety of human eyes, and the detection range of more than 10km can be reached, so that the limitation that the detection distance of the traditional laser radar is only 500m is broken; according to the invention, by selecting the 1550nm laser device which is safer to human eyes and greatly improving the laser power to kilowatt and even myriawatt levels, stronger echo signals are realized, so that the detection signal-to-noise ratio is remarkably improved; the micro-lens array is adopted to replace a traditional DOE diffractive optical element, efficient beam shaping of a one-dimensional or two-dimensional dot matrix is achieved through flexible regulation and control of the curvature radius and the distance of the micro-lenses, meanwhile, the manufacturing cost is reduced, and the design freedom degree is expanded.

The embodiment of the utility model provides a gas sensor chip with a lens. The gas sensor chip comprises a silicon lens array structure and a chip body, the silicon lens array structure comprises a silicon substrate and a plurality of optical filters; the silicon substrate is provided with a first surface and a second surface which are opposite to each other, and a lens array is formed on the first surface; the optical filter is arranged on the second surface of the silicon substrate; the position of the lens corresponds to that of the optical filter; the first surface of the silicon substrate is integrally connected with the upper surface of the chip body; wherein the lens corresponds to the central hot end of the chip body in position and is used for converging energy of an external infrared light source to the central hot end of the chip body. According to the chip, the optical filter is integrated on the chip body, and the lens array is formed on the silicon substrate of the optical filter carrier, so that the lens can gather the energy of an external infrared light source to the central hot end of the chip body, and the sensitivity of the chip is improved.

A low-beam headlight includes a light source arrangement for generating a light cone consisting of light that is less divergent in a first transverse direction than in a second transverse direction perpendicular to the first transverse direction. The low-beam headlight includes beamforming optics for generating, on the basis of light, a light / dark distribution comprising a light / dark edge extending obliquely at least in portions with respect to the first transverse direction and the second transverse direction, wherein the beamforming optics comprises a condenser lens array for receiving incident light, and a projection lens array with a multitude of projection lenses for outputting light received by the condenser lens array. Compared to a second projection lens assigned to a second condenser lens of the first column, a first projection lens assigned to a first condenser lens of the first column of the matrix is decentered differently with respect to the assigned condenser lens along the second transverse direction.

The invention discloses a Micro-LED light extraction structure, which relates to the field of photoelectricity and comprises first glass for bearing the light extraction structure, a photoresist curing film layer which is arranged on the first surface of the first glass structure and is imprinted and cured by a PDMS template, and a micro lens array arranged on the second surface of the first glass structure, and the surface of the micro-lens array is matched with the PDMS template to be subjected to surface roughening through a nanoimprint process. Meanwhile, the invention further discloses a preparation method of the Micro-LED light extraction structure. According to the invention, a set of PDMS template is adopted to respectively carry out roughening treatment on the glass surface and impressing transfer roughening treatment on the lens surface, so that the light emitting rate is improved, and the light extraction rate of the whole Micro-LED is effectively improved.

A camera module includes an imaging lens assembly module and an image sensor. The image sensor is disposed on an image surface of the imaging lens assembly module and includes a photoelectric converting layer, a micro lens arrays layer, a light filtering layer and an anti-reflecting layer. The photoelectric converting layer is for converting a light signal to an electric signal. The micro lens arrays layer is for converging an energy of the imaging light into the photoelectric converting layer. The light filtering layer is for absorbing a light at a certain wavelength region of the imaging light. The anti-reflecting layer is disposed on a surface of at least one of the light filtering layer and the micro lens arrays layer and includes an irregular nano-crystallite structure layer and an optical connecting layer. The optical connecting layer is connected to the irregular nano-crystallite structure layer.

The invention discloses a light field display system based on collimated light and multiple light control, and relates to the field of three-dimensional display. The system is provided with a diaphragm array layer which can limit the light emitting angle of a light source layer; the square lens array layer is arranged, light emitted by the light source layer can be converted into collimated light, and the directivity of the light is guaranteed; the orthogonal prism sheet layer is arranged, so that light rays are homogenized in two dimensions, and brightness balance of all parts of a final display area is ensured; pixel light rays are projected to different positions in a space through the light control grating layer, so that left and right eyes can see different image information respectively to form stereoscopic vision; the unidirectional diffusion layer is arranged above the light control grating layer, light rays are diffused in a unidirectional manner, and the same three-dimensional effect is generated at different positions in the vertical direction; and reverse compensation is carried out through a diffusion error compensation algorithm, so that observers at different positions can obtain consistent visual experience, and finally, a three-dimensional light field display effect with uniform brightness and low crosstalk is presented.

A thickness-distribution measurement device includes a light source; a light detector; and a control device. The light source irradiates a region of an object being conveyed with light, the region extending in a width direction. The light detector detects emitted light that has transmitted through the object. The control device obtains information on a distribution of a relative thickness of the object in the width direction based on a detection result in the light detector. The light detector includes an image sensor and a lens array. The image sensor includes a plurality of pixels arranged in the width direction, and detects an intensity of the emitted light for each pixel. The lens array includes a plurality of lenses having an equal magnification and arranged along the width direction, and collects the emitted light and forms an image of the emitted light on the image sensor.