74 results about "Optical path length" patented technology

The invention relates to the technical field of optical imaging, and discloses an AR optical projection machine and an optical display system, the projection machine comprises a projection lens group, a color combination prism assembly and a three-color display array; the projection lens group comprises a diaphragm STO, a first lens, a second lens, a third lens and a fourth lens. The color combination prism assembly comprises a plurality of prisms which are glued with one another, and a film coating structure which is used for reflecting red light and blue light and transmitting green light is arranged on each prism; the three-color display array comprises three display chips; wherein the FOV (field of view) of the AR optical projection machine is greater than or equal to 30 degrees and less than or equal to 40 degrees; the ratio of the total optical length TTL of the AR optical projection machine to the effective focal length f of the system meets the condition that TTL / f is larger than or equal to 5.0 and smaller than or equal to 7. The field angle of the system is limited within the range of 30-40 degrees, the ratio of the total optical length TTL to the effective focal length f is kept within 5.0-7.7, an imaging field meeting the AR application requirement can be obtained within the limited optical path length, meanwhile, the overall compactness of the optical system is considered, and the optical system can be more easily integrated into small-size near-to-eye display equipment.

The invention discloses a two-photon N00N quantum state intelligent regulation and control device and method, and the device comprises an intelligent regulation and control module, and an entangled photon pair generation module, an HOM interferometer and a data collection module which are connected in sequence, and the entangled photon pair generation module transmits polarized orthogonal entangled photon pairs to two light paths in the HOM interferometer respectively; the data acquisition module is used for detecting and counting photons output by the two light paths respectively; the intelligent regulation and control module controls the first electric control time delay line on one light path and the electric control polarization controller on the corresponding light path so as to regulate the light path difference of the two light paths and the polarization state of photons output by the corresponding light path; every time control is completed, a second electric control time delay line on the other light path is controlled to carry out time delay scanning according to a set rule, and a coincidence counting rate and HOM visibility are obtained; and according to the coincidence counting rate and the HOM visibility, determining whether the two-photon N00N quantum state generated under the control is good or bad. According to the invention, intelligent regulation and control of the two-photon N00N quantum state quality can be realized.

Provided is a pulse width expansion device for expanding the pulse width of a pulsed laser beam, the pulse width expansion device including a first optical pulse stretcher, a second optical pulse stretcher, a third optical pulse stretcher, and a fourth optical pulse stretcher disposed on the optical path of the pulsed laser beam, the first optical pulse stretcher, the second optical pulse stretcher, the third optical pulse stretcher, and the fourth optical pulse stretcher being disposed on the optical path of the pulsed laser beam. The optical path length of the delay optical path of the first optical pulse stretcher is L1, the optical path length of the delay optical path of the second optical pulse stretcher is L2, the optical path length of the delay optical path of the third optical pulse stretcher is L3, and the optical path length of the delay optical path of the fourth optical pulse stretcher is L4. When n is an integer of 2 or more, L2 is an integer multiple of 2 or more of L1, L3 satisfies (n-0. 75) * L1 < = L3 < = (n-0.25) * L1, and L4 satisfies (n-0.25) * L1 < = L4 < = (n + 0.25) * L1.

The present invention provides an interference measurement method and apparatus that can appropriately measure the physical properties of a sample in a non-contact manner. [Solution] The interference measurement method using the interference measurement device 1 includes: a first step of obtaining a first interference waveform W1 for each optical path length difference in the first state by performing measurements while changing the optical path length difference between the first optical path P1 and the second optical path P2 in a first state in which no sample S is placed in the second optical path P2; a second step of converting the first interference waveform W1 into a first electric field amplitude waveform WE1; a third step of obtaining a second interference waveform W2 for each optical path length difference in the second state by performing measurements while changing the optical path length difference in a second state in which a sample S is placed in the second optical path P2; a fourth step of converting the second interference waveform W2 into a second electric field amplitude waveform WE2; and a fifth step of obtaining measured values ​​regarding the physical properties of the sample S based on the electric field amplitudes corresponding to the peaks of the first electric field amplitude waveform WE1 and the second electric field amplitude waveform WE2, respectively.

A laser device includes an oscillator outputting pulse laser light; an amplifier amplifying the pulse laser light; an optical pulse stretcher extending a pulse width of the pulse laser light; a beam divergence angle adjuster including an upstream lens arranged on an optical path of the pulse laser light, a downstream lens arranged downstream of the upstream lens, and an optical path length changing mechanism for changing an inter-lens optical path length between the upstream lens and the downstream lens; and a processor controlling the beam divergence angle adjuster and obtaining a repetition frequency or a duty of the pulse laser light, and to change, when the repetition frequency or the duty changes by a preset threshold or more, the inter-lens optical path length so that the beam divergence angle of the extended pulse laser light becomes small in accordance with the repetition frequency or the duty after the change.

An optical computing system includes: an intensity modulation device group including at least two intensity modulation devices, each of which includes modulation cells, wherein each of the modulation cells of each of the intensity modulation devices carries out intensity modulation with respect to carrier light in accordance with one of signals to generate a signal light beam, and each of the signals corresponds to each of the intensity modulation devices; and a light diffraction element including diffraction cells having respective thicknesses or refractive indices set independently of each other, wherein each of the diffraction cells receives the signal light beam from each of the modulation cells of each of the intensity modulation devices corresponding to each of the diffraction cells, and by causing signal light beams to have respective different optical path lengths to the light diffraction element, the signal light beams have respective different phases.

The invention provides a double-pulse laser engraving method and device, and relates to the technical field of laser engraving, the double-pulse laser engraving method and device are used for engraving a gravure forme.The engraving method comprises the steps that the wavelength of femtosecond pulse laser and the wavelength of picosecond pulse laser are determined; determining the pulse delay of the femtosecond pulse laser and the picosecond pulse laser; determining a to-be-engraved area of the gravure plate; adjusting the optical path length of the femtosecond pulse laser and / or the picosecond pulse laser according to the pulse delay; synthesizing the femtosecond pulse laser and the picosecond pulse laser into double-pulse laser by using a polarization beam splitting cube; and ablating the to-be-engraved area according to the double-pulse laser. The femtosecond pulse laser is short in wavelength and high in energy, so that a to-be-engraved area can be pre-ablated quickly, when ungasified plasma is formed in the pre-ablated area, the picosecond pulse laser is used for performing secondary ablation on the pre-ablated area, the machining quality of the gravure plate can be guaranteed, the area of a heat affected area can be controlled, and the etching precision of an etched pattern can be improved.

Provided is a self-injection locking type laser device in which variations in environmental changes, optical path length, and resonator length are less likely to occur. The self-injection locking type laser device includes a first base plate, a second base plate, a temperature adjustment element disposed between the first base plate and the second base plate, a semiconductor laser light source disposed on the first base plate, a reference resonator disposed on the first base plate, located on an optical path of laser light emitted from the semiconductor laser light source, and including at least a first mirror and a second mirror for providing optical feedback to the semiconductor laser light source, a first cover covering the semiconductor laser light source and the reference resonator and in contact with the first base plate, and a second cover covering the first cover and in contact with the second base plate.

To provide a sensitivity measuring device and a sensitivity measuring method capable of measuring spectral sensitivity distribution of a light receiving element to be measured in a short time.SOLUTION: The sensitivity measurement device includes a light source, an optical system, a light collection mechanism, a position adjustment mechanism, a measurement unit, and an analysis unit. The optical system is configured to generate an interference wave by splitting light from a light source into two beams and causing the two beams to interfere with each other, and includes an optical path length difference changing mechanism configured to change an optical path length difference. The condensing mechanism condenses the interference wave at an irradiation position on the light receiving surface of the measured light receiving element. The position adjustment mechanism changes an irradiation position of the interference wave in a direction along the light receiving surface. The measurement unit controls the irradiation position and acquires a signal obtained by converting the interference wave from the light receiving element to be measured. The analysis unit calculates a component of the signal of each wavelength by Fourier transform of an interferogram obtained from the optical path length difference changed by the optical path length difference changing mechanism and the intensity of the signal measured by the measurement unit.SELECTED DRAWING: Figure 1

An interference measuring device 1A comprises a light source 10, an interference optical system 20A, a photomultiplier tube 30, an interference intensity measuring unit 40, a unit 50 for calculating the electric field amplitude, and an analysis unit 60. The light source 10 emits light in a band (a light band containing terahertz waves) to which the photomultiplier tube 30 is sensitive. The photomultiplier tube 30 is sensitive in a light band containing terahertz waves and outputs an electrical signal with a value corresponding to the intensity of the incident light.The unit 50 for calculating the electric field amplitude converts a value of intensity V of interference light, measured by the interference intensity measuring unit 40, into a value of electric field amplitude E, based on a relationship between a value of the electric field amplitude of light incident on the photomultiplier tube 30 and a value of the electrical signal output by the photomultiplier tube 30. It obtains the value of the electric field amplitude E of the interference light for each value of a time difference Δt, which corresponds to an optical path length difference Δd. Thus, an interference measuring device and an interference measurement method are realized that can perform Fourier spectroscopy by interference measurement using a terahertz wave quickly and accurately.

The dual-mode optical lens comprises a positive lens, a negative lens, a first turning mirror, a second turning mirror, a third turning mirror, a fourth turning mirror, an optical sensor and a machine shell, a linear sliding table is fixedly installed in the machine shell, and a moving part of the linear sliding table is in transmission connection with an installation frame; a second light hole is formed in one side of the top end of the mounting frame, a first light hole is formed in the bottom end of the other side of the mounting frame, the positive lens, the negative lens and the second light hole are located on the same horizontal line, and the first light hole and the light sensor are located on the same horizontal line; through the combination of the negative lens and the positive lens, a long focal length is realized under a relatively short optical path length, a more compact distance is realized through the two small-incidence-angle plane turning mirrors, and the two plane reflecting mirrors are combined and inserted into an optical path between the positive lens and the negative lens, so that light rays do not pass through the negative lens, and the optical path is more compact. And a relative small focal length light path corresponding to the positive lens directly reaches the sensor.

The invention relates to an optical path length adjusting device of a micro spectrophotometer for measuring the optical property of light passing through a sample. The optical path length adjusting device of a spectrophotometer according to the present invention comprises: a housing; a cover arm mounted so as to be rotatable about a hinge shaft provided on one side of an upper portion of the housing; a cover arm retainer on which the free end of the cover arm rests in the closed state; a lower base irradiated with light transmitted from a lamp installed inside the housing through an optical fiber; the upper base is supported by the cover arm and is positioned above the lower base; a lower base moving device configured to vertically move the lower base relative to the upper base; the spectrograph is configured to receive the light which is irradiated on the lower base and passes through the light path through the optical fiber and analyze and display the measurement characteristics of the sample, and the opposite surfaces of the lower base and the upper base are in a non-parallel state. The light path length adjusting device of the micro spectrophotometer is simple in structure, so that high-precision absorbance measurement can be carried out in an ultra-high concentration range without precise control.

A biological sample analysis system (100) according to an embodiment includes a detection optical system (121), a focal point of which is set at a predetermined position in a container (C), an imaging unit (122), a light receiving surface of which is located at an image forming position of an image of light transmitted through the detection optical system (121), and an optical path length adjustment element (13) disposed on an optical path between the detection optical system (121) and the imaging unit (122) and in a part within an angle of view of the imaging unit (121).

The utility model discloses a femtosecond laser pulse compression device. The device comprises an amplifier, a half-wave plate and a transmission-type compression grating which are sequentially arranged along a light path, a first climbing mirror and a second climbing mirror are arranged on a diffraction light path on one side of the transmission-type compression grating, and a third climbing mirror and a leading-out reflector are arranged on a diffraction light path on the other side of the transmission-type compression grating; and a cylindrical lens group is arranged between the transmission-type compression grating and the first climbing mirror and the second climbing mirror. According to the technical scheme, a single grating is matched with a plurality of climbing mirrors to form a laser turn-back system, compression of laser pulses is completed under the condition that the size of the laser pulse compression device is greatly reduced through a simple structure, a large dispersion providing amount can be achieved within a short optical path length through further arrangement of a cylindrical lens set, and therefore the laser pulse compression device has the advantages of being simple in structure, convenient to operate and high in efficiency. The set size of the device is further reduced, the miniaturization design of the femtosecond laser pulse compression device is facilitated, and the cost is reduced.

Wavefront measurement of a multi-core optical fiber is described. A multi-core optical fiber is configured to conduct radiation from a radiation source to a structure, such as a metrology target, in one or more layers of a patterned substrate, and to conduct diffracted and / or reflected radiation from the metrology target to a radiation sensor. The multi-core optical fiber has a length configured to facilitate placement of the radiation source and / or the radiation sensor in spaced locations relative to the patterned substrate. Optical path length differences between sets of fiber cores with reflectors in the multi-core optical fiber are determined for radiation of different wavelengths from the radiation source. The optical path length difference is determined based on a path length of reflected radiation that is incident on the radiation sensor after returning through the core set. The optical path length difference indicates wavefront distortion.

A depth extender for an imaging system includes an optical element having a radially correlated thickness deviation proportional to an oscillation function having a first envelope and a second envelope. The first envelope has an amplitude at each of a plurality of radial distances, the amplitude being substantially equal to the difference between: (i) a reference optical path length originating from a reference ray traveling in the radial distance within the object plane between a minimum and a maximum object distance, and (ii) the optical path length of a first ray traveling in the radial distance within the object plane at the minimum object distance. The second envelope has an amplitude at each radial distance substantially equal to the difference between: (i) the reference optical path length, and (ii) the optical path length of a second ray traveling in the radial distance within the object plane at the maximum object distance.

A digital lithography system includes a light source configured to emit a light beam along an optical path toward a substrate via one or more optical elements. The digital lithography system further includes a digital micro-mirror device (DMD) configured to receive the light beam and form an output light beam. The output light beam is emitted along the optical path toward the substrate. The digital lithography system further includes an imaging device configured to capture an image of the substrate illuminated at least in part by the output light beam. A first optical path length corresponding to the DMD and a second optical path length corresponding to the imaging device are unequal.

Provided is a laser interferometer capable of suppressing the incidence of return light on a laser light source and capable of suppressing a decrease in the precision of demodulation of a sampling signal originating from a measurement object based on a light reception signal. The laser interferometer includes a laser light source; a collimator that generates collimated light; a light modulator that modulates the collimated light into reference light having different frequencies; and a light reception element that receives object light and the reference light and outputs a light reception signal, the light axis of the collimated light is set as a first light axis, the light axis of the return light is set as a second light axis when the return light is generated, the position at which the collimated light is generated is set as a reference position, when the offset width of the first light axis and the second light axis in the reference position is set as Δy, the effective diameter of the collimator is set as κ, the optical path length of the collimated light is set as R, the distance from the reference position to the light modulator is set as L, and the wavelength of the collimated light is set as λ, the following expression (A) is satisfied

A method and corresponding apparatus for determining an absolute optical distance between two reflective surfaces constituting an interference cavity, the method comprising: moving an illumination spot in a rear focal plane of an interferometer along a trajectory having a non-zero radial component relative to an optical axis, enabling the irradiation light spot to move along different radial positions of the track, and synchronously acquiring an image of an interference pattern of the interference cavity; and analyzing the image using one or more electronic processors to determine a functional correlation of a difference in optical path length (OPD) of the interference cavity and a radial position of the illumination spot, and extracting an absolute optical distance between the two reflective surfaces based on the determined functional correlation.

The application relates to a fiber-optic gyroscope testing system. The system comprises a light source, a coupler with at least four end heads, a sensitive light path, a reference light path, a subtracter, an A / D module, an FPGA, a D / A module and a waveguide driver connected in sequence; the light emitted by the light source is divided into two paths by the coupler and then enters the sensitive light path and the reference light path respectively; the sensitive light path comprises photoelectric modulators, a sensitive fiber-optic ring, a coupler, a first photoelectric detector and a first preamplifier connected in sequence; the output end of the waveguide driver is in communication connection with the photoelectric modulators; the reference light path comprises a reference fiber-optic ring, a second photoelectric detector and a second preamplifier connected in sequence, and a compensation fiber with a preset length is connected in the reference light path, so that the optical paths of the sensitive light path and the reference light path are equal; the output ends of the first preamplifier and the second preamplifier are connected with the input ends of the subtracter respectively; the subtracter is used for subtracting the signal output by the first preamplifier from the signal output by the second preamplifier, so as to obtain a photoelectric signal with noise removed. The application can remove light source intensity noise and improve rotation speed demodulation precision.

The application relates to an absolute temperature calculation method and system based on an isotopic absorption spectrum line, equipment and a medium, and belongs to the technical field of temperature measurement. The method comprises the following steps: acquiring absorption spectrum lines of gas A and gas B on the same light path under the same light path and a to-be-measured temperature, and characteristic parameters of the gas A and the gas B, wherein the gas A and the gas B are different isotopic gases of the same substance; and obtaining the absolute temperature of the to-be-measured temperature according to the absorption spectrum lines and the characteristic parameters of the gas A and the gas B under the to-be-measured temperature. The method principle discards the traditional electrical temperature measurement principle, directly calculates the absolute temperature of the to-be-measured temperature based on the light absorption intensity of the different isotopic gases of the same substance, and solves the problems in the background art.

The application belongs to the technical field of analysis and detection, and relates to a data processing method and system of a water quality analyzer and a readable storage medium. The water quality analyzer comprises, in sequence along an optical path direction, a light source, a first lens, a filter, a dichroic spectroscope, a measuring pool, a second lens, an aperture diaphragm and a detector. A reference light beam reflected by the dichroic spectroscope converges into a reference detector through a third lens. The data processing method comprises the following steps: collecting energy values of each pixel point of the reference detector, searching for an energy peak value and searching for a first pixel point with an energy value not greater than half of the energy peak value from both sides of the energy peak value, obtaining pixel points X 1 and pixel points X 2, calculating a light source emission angle according to the pixel points X 1, the pixel points X 2 and a reference optical path length, correcting an incident light intensity according to an ambient temperature and the light source emission angle to obtain a corrected incident light intensity, and calculating an absorbance according to the corrected incident light intensity. The application effectively improves the analysis accuracy of the water quality analyzer.

The invention discloses a multi-gear optical fiber channel fusion depth detection OCT (optical coherence tomography) system, an optical path matching method and application, an optical fiber coupler is respectively connected with a reference optical path and a sample optical path system, in the reference optical path system, the optical fiber coupler is connected with a multi-gear optical fiber switching port through a reference optical path optical fiber, each interface of the port is connected with a switching optical fiber with a specific optical path length, and the switching optical fiber is connected with the sample optical path system. The other end of the switching optical fiber is connected with an optical fiber beam combiner and then sequentially passes through a reference arm beam expanding collimator and a focusing lens to a fixed reflecting mirror to form a reference light beam, a sample light path system passes through a sample arm beam expanding collimator, a two-dimensional scanning galvanometer and a field lens to reach a tested sample, and the tested sample returns to form a sample light beam; the preset lengths of the switching optical fibers are in one-to-one correspondence with the working distances of different field lenses, and when the field lenses are replaced, the reference optical path optical fibers are inserted into the corresponding interfaces so as to compensate the optical path difference caused by replacement of the field lenses. According to the invention, the optical path adjusting function is compressed to be within the size of a standard optical fiber device, and the optical path conversion from tens of centimeters to meters is realized in a small volume.

An interferometer based on an atomic force microscope ("AFM") uses a light source and a beamsplitting optical interface to split a light beam into a signal beam and a reference beam. Both the signal beam and the reference beam are focused near an AFM cantilever. A beam displacer introduces a lateral displacement between the signal beam and the reference beam that causes the center of the signal beam to be separated from the center of the reference beam by more than half the sum of their beam diameters in at least one plane between the beam displacer and a focusing lens structure. A detector operates to determine a difference in the optical path length between the signal beam and the reference beam to determine information about movement of the cantilever.

The invention provides an optical element, an image display unit and a head-mounted display capable of increasing the optical path length and improving the light utilization efficiency. This optical element has, in the following order: a first absorption-type linear polarizer; a first reflective linear polarizer; a first phase difference sheet; a partially reflecting mirror that partially reflects and transmits a portion of the incident light; a second phase difference sheet; and a second reflective linear polarizer, the rotation direction of the circularly polarized light reflected by the first reflective linear polarizer when light is incident on the first reflective linear polarizer through the first phase difference sheet and the rotation direction of the circularly polarized light reflected by the second reflective linear polarizer when light is incident on the second reflective linear polarizer through the second phase difference sheet. The rotation directions of the circularly polarized light reflected by the second reflective linear polarizer are opposite.

The application relates to the technical field of ophthalmic medical equipment, and discloses a light path difference regulation system which comprises a light source module, a light path regulation module, an optical projection module, a neural adaptation detection module and a central control module; the light path regulation module and the neural adaptation detection module are arranged, the light path difference dynamic modulation is applied to ophthalmic treatment, the problem is solved from the trigger source of neural adaptation by changing the phase distribution mode of retinal light stimulation, the problem is indirectly relieved by adjusting the intensity or frequency, and the adjustment of the modulation parameters is based on the detection result of the neural adaptation detection module, so that the modulation is effective and does not cause additional discomfort; feedback control is completed through the central control module, a closed-loop system of detection-feedback-adjustment is realized, the modulation parameters can be dynamically optimized and adjusted according to the individual neural adaptation degree, and the individualization level of treatment can be effectively improved.

The application provides an echo wall mode microcavity magnetic sensor and a detection method. The echo wall mode microcavity magnetic sensor comprises an echo wall mode microcavity, a magnetostrictive layer and a base. The magnetostrictive layer is in contact with the echo wall mode microcavity, and the base is in contact with the echo wall mode microcavity and used for supporting the echo wall mode microcavity. The application combines the echo wall mode microcavity with the magnetostrictive layer, so that the magnetostrictive layer produces resonance under a magnetic field to produce a mechanical response, thereby changing the optical path length of the echo wall mode microcavity in contact with the magnetostrictive layer, further changing the resonance frequency of the echo wall mode microcavity, and the size of the magnetic field and the movement of the resonance frequency are in linear relationship, so that the echo wall mode microcavity magnetic sensor has high sensitivity and is suitable for different magnetic field detection, especially for biological magnetic detection with low magnetic field strength and low frequency.

Provided is an optical receiver which can be manufactured by a simple mounting method, and achieves both high sensitivity and miniaturization by extension of an optical path length. An optical receiver according to the present disclosure includes a planar light wave circuit which includes a spot size converter for converting a spot size of signal light incident from an optical fiber; a semiconductor substrate connected to the planar light wave circuit via a connecting surface; and a light-receiving element mounted on a substrate surface of the semiconductor substrate, in which the connecting surface is a facet surface that is in contact with the substrate surface at an acute angle or an obtuse angle so that the signal light emitted from the spot size converter is incident on a light-receiving surface of the full light-receiving element.

The invention discloses a GIS (Gas Insulated Switchgear) metal particle defect distributed detection system, a terminal and a storage medium, a bidirectional interference structure is introduced, the system utilizes a forward light path and a reverse light path formed by light splitting of a first coupler, and light phase disturbance generated at a sound vibration action point can be propagated to an interference point along two directions respectively; a measurable time offset is formed due to propagation path differences. According to the system, on the basis of the time difference, the delay amount is accurately obtained through a cross-correlation algorithm, back calculation is carried out in combination with the length of the reference optical fiber and the length of the guide optical fiber, an acoustic emission event can be mapped to a specific position in an optical fiber path, and therefore high-precision, continuous and multi-point-synchronization-free defect positioning is achieved. Distributed sensing and a bidirectional optical path difference positioning mechanism are combined, so that the system not only can detect weak acoustic emission events, but also can accurately determine the actual position of a metal particle defect in a GIS (Geographic Information System), and the detection range, the positioning precision and the economical efficiency of the device are remarkably improved.

The application discloses a kind of marine interface pollutant spatial distribution observation methods, it is related to marine environmental optical remote sensing monitoring technical field.The present application is according to the characteristics of sunlight spectrum sea surface reflection, selects solar sea surface glint as light source, improves the signal-to-noise ratio of spectral signal when collecting, simultaneously, the sunlight of specular reflection is no longer refracted into seawater, and will not change the atmospheric absorption structure of solar spectrum;When solar sea surface glint occurs reflection on sea surface, incident light is direct sunlight, and direct sunlight has a certain angle of incidence, so using solar sea surface glint as light source has clear observation geometry mode, can accurately calculate the optical path length of solar spectrum after absorbing near-sea surface atmospheric pollution gas, to accurately retrieve the concentration of relevant sea area near-sea surface atmospheric pollution gas, by setting equidistant observation angle in turn along the direction of solar sea surface glint, the distance resolution measurement of sea surface pollution gas can be realized.