211 results about "Extinction ratio" patented technology

The invention discloses a parameter measuring device and method of an optical switch and optical communication equipment, and relates to the technical field of optical switch measurement, and the parameter measuring device of the optical switch comprises an optical path module, a signal conditioning circuit, a driving module, a signal acquisition module and an upper computer. The optical path module converts the optical signal into a current signal; the signal conditioning circuit conditions the signal into a voltage signal and amplifies the voltage signal; the driving module provides a driving signal and a synchronous triggering signal; the signal acquisition module acquires a voltage signal based on the trigger signal; the upper computer calculates performance parameters of the optical switch according to the voltage signals acquired for multiple times, wherein the performance parameters at least comprise two items of insertion loss, extinction ratio, switching time and the like; according to the technical scheme, one-key measurement of performance parameters such as insertion loss, extinction ratio, switching time, polarization-dependent loss, insertion-dependent loss and repeatability of the optical switch can be realized, meanwhile, the measurement cost of the optical switch is reduced, and the test efficiency and accuracy are improved.

The invention relates to the field of performance testing of high-precision fiber-optic gyroscopes, and discloses an automatic testing method and system for the extinction ratio of a high-precision fiber-optic gyroscope, and the method comprises the following steps: constructing a signal light path and a reference light path, and combining the output light of the signal light path and the reference light path into a combined light signal in an orthogonal polarization state; integrally measuring the extinction ratio of the combined optical signal by using an extinction ratio tester to obtain a measured value; the control unit compares the measured value with a target value of 0dB and generates a control instruction based on a difference value; the voltage controller automatically adjusts the voltage of the integrated optical modulator in the signal light path according to the instruction, and iterative optimization is carried out through closed-loop feedback until the actually measured extinction ratio reaches a target value; and finally recording and solidifying the optimal voltage value. According to the invention, single and accurate extinction ratio overall measurement is used for replacing two times of error-prone independent optical power measurement, full-automatic closed-loop control is realized, the precision, efficiency and consistency of optical power balance are remarkably improved, and the skill requirements on operators are reduced.

The invention relates to a laminated staggered sub-wavelength polarization grating structure and a preparation method thereof, through staggered arrangement of a first metal grating layer and a second metal grating layer, transmission of polarized light of a transverse electric field can be effectively inhibited, and the extinction ratio is remarkably improved. Through the substrate, the first dielectric layer, the second dielectric layer, the first metal grating layer, the third dielectric layer and the second metal grating layer which are sequentially arranged from bottom to top, the whole device obtains a higher extinction ratio while keeping high transmittance, the overall structure is simple, the processing difficulty and cost are reduced, and the production efficiency is improved. And the number of the used dielectric layers and metal layers is small, the thickness requirement is low, and therefore it is ensured that the cost is controllable.

The invention discloses a polarization sensitive type broadband absorber based on metal-medium stacking, and relates to the technical field of micro-nano photonic devices and infrared detection. The absorber sequentially comprises a bottom-layer high-loss metal reflecting layer, a multi-layer stacked composite dielectric cavity structure and a top-layer sub-wavelength metal grating from bottom to top, according to impedance matching and interference resonance theories, a broadband absorption substrate is constructed through a multi-layer film structure at the bottom, and light energy is converted into heat energy by utilizing the high loss characteristic of bottom layer metal; plasmon resonance is excited through the top metal grating, the coupling efficiency of TM polarized light is enhanced, and TE polarized light is cut off; the above structural design successfully realizes efficient broadband absorption and high polarization extinction ratio in an infrared band. The structure is simple in design, is compatible with a CMOS technology, and has excellent wide-angle stability. And meanwhile, polarization screening can be realized without an external polaroid, and miniaturization and integration of an infrared detection system are facilitated.

The invention discloses a thin-film barium titanate electro-optical switch unit based on a composite electrode and an array thereof. The optical switch unit comprises a first waveguide optical fiber coupling module, a second waveguide optical fiber coupling module, an optical beam splitting module, an electro-optical phase shift region, an optical beam combining module, a third waveguide optical fiber coupling module and a fourth waveguide optical fiber coupling module. Wherein the composite electrode of the electro-optic phase shift region is composed of a metal electrode and a transparent conductive layer, the electrode is closer to the waveguide by utilizing the transparent characteristic of a transparent conductive material, the coupling of a light field and an electric field is effectively enhanced, and the extinction ratio is improved. Meanwhile, a barium titanate film with a high electro-optical coefficient is adopted as a waveguide material, and the performance is further optimized, so that the electro-optical switch unit has the excellent characteristics of low-voltage driving, high extinction ratio, low insertion loss and small size.

An integrated configurable photodetector with an ultra-high circular polarization extinction ratio and a preparation method therefor are provided. The photodetector includes a metal reflective layer, a dielectric layer, an electrode layer, and a two-dimensional material layer. The electrode layer includes symmetrically arranged Z-shaped metallic optical antenna arrays which are respectively integrated with a source electrode and a drain electrode and have opposite chirality. The photodetector operates at zero bias state, and a photo-response is photovoltaic effect, hot electron injection, photo-thermoelectric effect and so on induced by a Schottky junction composed of the source electrode, the drain electrode and the two-dimensional material. By adjusting the distribution of the incident light in the source and drain electrode regions, under specific Circularly polarized light, photocurrents of equal magnitude but opposite directions cancel each other out, resulting in a net output of zero and significantly reducing noise.

The invention relates to the technical field of optical communication, and provides a polarization separation rotator and optical communication equipment. The polarization separation rotator comprises an input coupling waveguide, a ridge waveguide and a separation waveguide, and the input coupling waveguide, the ridge waveguide and the separation waveguide are sequentially arranged in the light propagation direction; the input coupling waveguide is used for coupling an input optical signal to the ridge waveguide, and the input optical signal comprises two polarization modes; the vertical section of the ridge waveguide is in a step shape to form a vertical asymmetric structure, and the vertical section is perpendicular to the light propagation direction. And the separation waveguide is used for separating the optical signals in the two polarization modes so as to respectively transmit the optical signals to different output ports. According to the polarization separation rotator provided by the invention, the defects that the size is difficult to further reduce and the polarization extinction ratio is reduced in the prior art are overcome, efficient polarization mode hybridization is realized by increasing the asymmetry in the vertical direction, and miniaturization of the polarization separation rotator is facilitated.

The invention relates to the technical field of optical communication, in particular to a silicon optical chip monitoring method and device, electronic equipment and a computer readable storage medium, and the method comprises the steps: obtaining an input monitoring value and an output monitoring value integrated by a silicon optical chip, the input monitoring value is an input optical power value collected by an input monitoring photodiode integrated with the silicon optical chip, the output monitoring value is an output optical power value collected by an output monitoring photodiode integrated with the silicon optical chip, and a power ratio parameter is calculated according to the input monitoring value and the output monitoring value; the power ratio parameter is compared with a preset ratio range, and when it is detected that the power ratio parameter is not in the preset ratio range, it is determined that the silicon optical chip has an optical extinction ratio abnormal risk; and outputting a detection result containing the risk that the optical extinction ratio is abnormal, so that the real-time performance of abnormal detection of the optical extinction ratio of the silicon optical chip is improved.

A system for a waveguide-based diplexer (wavelength multiplexer / demultiplexer) and polarizer having ultra-broad bandwidth, a compact footprint, low losses, fabrication robustness and a simple single etch fabrication process. The polarizer (TE-pass) is based on the phase-matched coupling of the unwanted TM0 mode in an input waveguide to the TM1 mode in a tapered directional coupler (DC), which is then guided through a low-loss bend (180-degree) and scattered in a terminator section with low back reflections. An S-bend is added before the output for filtering any residual TM0mode present in the input waveguide. The diplexer is based on a multimode interference (MMI) coupler and is designed at the first imaging length for 1550 nm wavelength resulting in a compact MMI length. In order to improve the extinction ratio, the output ports are made asymmetric in width.

This invention discloses a bimetallic hybrid metasurface that achieves polarization-selective absorption and tunable liquid immersion. The metasurface consists of a three-layer structure: a bimetallic hybrid layer, a silicon dioxide layer, and a silver reflective layer. The bimetallic hybrid layer is composed of aluminum and titanium nanoribbons. The bimetallic hybrid metasurface achieves perfect absorption of incident light under x-polarized light at the resonant wavelength and specular reflection of incident light under y-polarized light, thus exhibiting a high extinction ratio. Furthermore, the absorption peak wavelength of the metasurface can be continuously and dynamically tuned by adjusting the unit period of the metasurface or by utilizing active tuning through liquid immersion. The bimetallic hybrid metasurface proposed in this invention achieves high-contrast polarization-selective absorption and possesses advantages such as simple structure, ease of integration, and dynamic tunability, thus it can be widely applied in practical applications such as novel optical polarizers and photodetectors.

The application discloses a kind of parameter measuring device of optical switch and method, optical communication equipment, it is related to optical switch measurement technical field, the parameter measuring device of optical switch includes optical path module, signal conditioning circuit, drive module, signal acquisition module and host computer;Optical path module converts optical signal into current signal;Signal conditioning circuit is conditioned as voltage signal and amplifies;Drive module provides driving signal and synchronous trigger signal;Signal acquisition module is based on trigger signal and collects voltage signal;Host computer calculates the performance parameter of optical switch according to voltage signal collected multiple times, and performance parameter at least includes two items in insertion loss, extinction ratio, switching time etc.;The technical scheme of the application can realize the one-key type measurement of the performance parameter such as insertion loss, extinction ratio, switching time, polarization dependent loss, insertion dependent loss and repeatability of optical switch, while reducing the measurement cost of optical switch, improve test efficiency and accuracy.

The present disclosure provides a middle wave infrared integrated polarization detector and a preparation method. The middle wave infrared integrated polarization detector comprises a plurality of polarization gratings arranged in a periodic array, a dielectric film layer and a middle wave infrared detection chip arranged in sequence. The middle wave infrared detection chip has a plurality of pn junction regions arranged in a periodic array. The pn junction regions are arranged one by one corresponding to the polarization gratings. The middle wave infrared detection chip has a plurality of isolation grooves. The isolation grooves are arranged between adjacent two polarization gratings. The isolation grooves are filled with isolation pieces. By arranging the isolation pieces in the middle wave infrared detection chip, the polarization light crosstalk of adjacent two polarization gratings is suppressed, and the extinction ratio of the middle wave infrared integrated polarization detector is improved. The preparation method of the present disclosure uses nanoimprint technology to directly process nanoscale polarization gratings on the dielectric film layer, which can improve the processing efficiency and reduce the processing cost.

The present invention provides a quantum entanglement light source device that takes advantage of the benefits of using optical fibers and can compensate for the decrease in polarization extinction ratio with a simple configuration. [Solution] A quantum entanglement light source device according to one embodiment of the present invention comprises a wavelength conversion unit capable of generating polarized light with a wavelength longer than the wavelength of the pump light, and a polarization control unit provided midway through optical fibers provided on both end faces of the wavelength conversion unit, capable of controlling the polarization direction of the pump light in the wavelength range.

The present invention relates to the field of integrated optics and provides a spot converter comprising: a substrate layer; an input waveguide disposed on the substrate layer and having a greater refractive index than the substrate layer; an output waveguide disposed on the substrate layer and having a greater refractive index than the substrate layer; and a surface plasmon waveguide disposed between and in communication with the input and output waveguides, configured to induce a surface plasmon effect in electromagnetic waves transmitted from the input waveguide. The present invention effectively addresses the issues of large size and low extinction ratio in conventional spot converters, thereby achieving a compact size and high extinction ratio, saving raw material and process costs.

The invention discloses a pulse modulation laser array chip based on a double-SOA structure, which relates to the technical field of photoelectronics and comprises a substrate, a semiconductor laser array chip, an active photon integrated chip and a photon lead waveguide structure, the semiconductor laser array chip and the active photon integrated chip are arranged on the substrate; the semiconductor laser array chip and the active photonic integrated chip are in coupling connection through a photonic lead waveguide structure, the active photonic integrated chip comprises an SOA wave combining chip or an SOA chip, and the semiconductor laser array chip comprises a first SOA structure. According to the invention, a double-SOA structure is used, the problem of light leakage in a common laser array is solved, a larger modulation range and extinction ratio are realized, combined wave emission of a plurality of laser arrays is realized, the number of laser channels is increased, and the wavelength tuning range is expanded.

The invention discloses a middle infrared band microstructure optical fiber polarization beam splitter, the polarization beam splitter comprises a centrosymmetric cladding and two fiber cores, the cladding and the fiber cores are composed of a substrate material GaS and air holes, and the cladding is located on the outer side of the fiber cores. The cladding is composed of first air circular holes and second air circular holes, and the plurality of first air circular holes are periodically arranged in a triangular lattice structure. The fiber core is composed of a first elliptical air hole, a second elliptical air hole, a third air round hole and a fourth air round hole, and the fiber core is located between the first elliptical air hole and the second elliptical air hole and is a solid core filled with a GaS substrate material. The length of the micro-structure optical fiber polarization beam splitter of the middle-infrared band is only 40 microns, and the extinction ratio at the wavelength of 4.42 microns can reach-70 dB; and single polarization output can be realized in a range of 4.29 [mu] m to 4.59 [mu] m. The device has the advantages of small size, high extinction ratio, large bandwidth and the like, adopts a single material, effectively reduces the manufacturing difficulty of the device, is easy to integrate and miniaturize, and has potential application value in the fields of mid-infrared optical fiber sensing, mid-infrared band communication, mid-infrared band environment detection, optical nonlinearity and the like.

The application discloses a continuous variable quantum key distribution method based on an inner modulation pulse light source, which comprises the following steps: a sending end provides signal light and local light to a receiving end, or the sending end provides signal light to the receiving end, and the receiving end provides local light; the receiving end interferes the signal light and the local light, and extracts a component with channel noise and initial data from the interference result; and the receiving end processes the component with channel noise and the initial data to obtain amplitude modulation information related to the channel noise, namely, an initial key. The application makes full use of the random phase difference between the front and rear pulses generated by the inner modulation pulse light source, and makes the detection result independent of the phase difference, without any phase feedback and compensation, and the modulation mode is simpler; higher light pulse extinction ratio and light pulse intensity can be obtained, so that the transmission distance is farther, and the detection efficiency is higher; the high complexity double light source frequency locking technology can be avoided, and the system complexity is reduced.

A high extinction-ratio rotator includes a collimator that can collimate a signal light from an optical fiber, a pair of polarizing splitting prisms that include a first birefringence crystal wedge and a second birefringent crystal wedge, that can separate two orthogonal polarization components of the signal light into a vertically polarized light and a horizontally polarized light, a non-reciprocal 45-degree polarization rotator which the vertically polarized light and the horizontally polarized light exiting the pair of polarizing splitting prisms pass through, and a reflector. The vertically polarized light and the horizontally polarized light exiting the non-reciprocal 45-degree polarization rotator intersect on a surface of the reflector and are reflected back into the non-reciprocal 45-degree polarization rotator.

The present invention discloses an integrated, dynamically controlled, high-selectivity infrared polarization detector and a method for fabricating it. The detector relates to the field of optoelectronics. The detector comprises, from bottom to top, a substrate layer, a metal reflective layer, a dielectric layer, and an electrode layer, further comprising a two-dimensional material layer. The electrode layer comprises a source electrode, a drain electrode, a metal two-dimensional metamaterial integrated in the source electrode, and a metal two-dimensional metamaterial integrated in the drain electrode. The source and drain electrodes are symmetrically arranged, with a channel provided between them. The two-dimensional material layer spans the channel and is electrically connected to the source and drain electrodes. When the detector operates in a zero-bias state, the optical response is derived from the photothermoelectric effect induced by the Schottky junction formed by the source and drain electrodes and the metal two-dimensional metamaterial. The carrier concentration of the graphene in the source and drain electrodes is controlled by the metal reflective layer, and the polarization extinction ratio and direction of the photocurrent are controlled under illumination of linearly polarized light at any specific angle. The present invention achieves an infinite extinction ratio and a zero photocurrent response at any polarization angle.

The invention discloses a high-speed and high-extinction-ratio cascade MZI (Mach Zehnder Interferometer) electro-optical switch based on an electro-optical material. According to the electro-optical switch, a plurality of MZI structures are cascaded and integrated on an electro-optical material platform (such as lithium niobate or lithium tantalate) with an ultra-wide optical transparent window, and the initial phase error of each modulation arm is subjected to thermo-optical calibration by utilizing the refractive index change of an electro-optical material caused by temperature regulation and control; therefore, the consistency and long-term stability of the initial phase of the cascaded MZI are ensured. After thermo-optical phase calibration is completed, electro-optical refractive index regulation and control can be carried out on a plurality of phase modulation arms of the cascaded MZI at the same time only by applying a single driving voltage, and optical switch switching with the ultrahigh extinction ratio is achieved. The device has a pre-calibration function, a working point is stable and does not drift after calibration, and high-speed and high-extinction-ratio switching can be achieved only through a high-speed signal; and meanwhile, the device has the advantages of simple structure, flexible design, easiness in cascade expansion, low requirement on technological parameter tolerance and the like.

The present invention discloses an optical gyroscope integrated chip based on a thin-film lithium niobate photonic integrated platform. The overall structure adopts a hybrid curved waveguide with multiple parts of continuously variable curvature, which reduces the insertion loss caused by the mode field mismatch between the straight waveguide and the curved waveguide at the junction, reduces the excitation of high-order modes, and helps to reduce the overall size of the chip. In addition, the curved waveguide increases the polarization extinction ratio of the chip and filters out quasi-TE 00 The present invention utilizes waveguide mode leakage to achieve single-mode, single-polarization operation of the lithium niobate waveguide. The single-TE mode lithium niobate waveguide on the entire chip, excluding the curved waveguide of the folded modulator and the coupler, forms a waveguide polarizer with a high polarization extinction ratio. This allows on-chip single-mode, single-polarization operation to be achieved without the need for an additional polarizer design, effectively reducing chip complexity, improving chip stability, and reducing chip size.

This application relates to the field of optical polarization measurement technology, specifically to a wide-spectrum, high-bandwidth static spectral modulation Stokes polarization measurement device, comprising a polarization modulation module, a spectral sampling module, and a high extinction ratio polarizer. The polarization modulation module includes a phase retarder and a linear polarizer; the spectral sampling module has sub-nanometer spectral resolution; the high extinction ratio polarizer includes a halogen tungsten lamp and a Glan Taylor prism for generating high-purity linearly polarized light; the obtained demodulation factor and the modulation spectrum acquired by the spectral sampling module are used to invert the Stokes parameters using zero-heterodyne coherent demodulation technology. This application employs a phase retarder with high birefringence, which, for the same thickness, produces an optical path difference tens of times greater than that of quartz, increasing the Stokes polarization measurement bandwidth by a factor of the response and improving the measurement accuracy of polarization spectral parameters. Simultaneously, the zero-heterodyne coherent demodulation method is used to eliminate the dispersion interference of the phase retarder through calibration.

The invention relates to the technical field of optical module automatic detection, in particular to an optical module automatic detection system and method based on a numerical control robot, and the method specifically comprises the steps: constructing a connection judgment factor through analyzing the optical signal intensity, the optical signal extinction ratio, a Q factor, the distribution condition of abnormal points in current data, and the data fluctuation condition near each abnormal point; by analyzing the abnormal data change of the current, the statistical significance difference between the current data and other parameters is reflected by using a t test algorithm, and a connection risk index during optical module detection is constructed; the connection quality of the optical module is monitored in real time through the connection risk index, when the poor degree of connection is serious, a control signal is sent out through the control module to indicate the six-axis manipulator to pull and plug the optical module again, detection errors caused by connection problems are reduced, it is ensured that the optical module is tested in the optimal state, and the test efficiency is improved. And the accuracy of optical module performance judgment is improved.

This invention relates to the field of optical thin film fabrication technology, specifically to a method for fabricating a high extinction ratio, adhesive-free polarizing beam splitter film resistant to high and low temperature environments. The method includes the following steps: S1, substrate pretreatment; S2, polarizing beam splitter film deposition; S3, adhesive-free bonding treatment; S4, annealing strengthening; and S5, post-treatment. This invention uses an adhesive-free optical contact bonding process to replace the traditional organic bonding process, completely eliminating the temperature adaptability bottleneck caused by organic adhesive layers. The bonding interface relies on intermolecular forces for adhesion, eliminating problems such as aging and debonding of organic adhesives. This allows the device to operate stably in a wide temperature range of -60℃ to 120℃, greatly improving the device's environmental adaptability and meeting the needs of extreme environments such as deep space exploration and polar observation.

The invention relates to the technical field of biological detection, and provides a biological tissue component detection device and a detection method. The biological tissue component detection device comprises a laser unit, a sample table, a polarization unit, a detector, a first scanner and a processor, the polarization unit is used for reflecting the S polarized light emitted by the laser unit to the biological tissue and filtering out the S polarized light in the mixed light reflected by the biological tissue; the detector is used for collecting light intensity of theta polarized light; the first scanner is used for acquiring space coordinates of each region of the biological tissue; and the processor is used for generating a polarization angle spectrum of the single region based on the light intensity and the polarization angle, generating a global polarization angle spectrum of the biological tissue based on the plurality of polarization angle spectrums and the plurality of space coordinates, and detecting the biological tissue based on a peak polarization angle, a spectrum width and a polarization extinction ratio of the global polarization angle spectrum. According to the biological tissue component detection device, spectrum similar substances in multiple industries can be distinguished, and the biological tissue distinguishing accuracy is improved.

The invention relates to the technical field of optical transceivers, and discloses a high-extinction-ratio coherent optical silicon optical transceiver chip and a transmitting method and a receiving method thereof. The transmitting end of the chip comprises a structure formed by cascading a modulator (102) and an optical switch (103); the receiving end comprises a simplified receiving structure consisting of a 2 * 2 coupler (104) and a single photoelectric detector (105); and all devices are integrated on a single silicon optical chip. According to the invention, the cascade architecture of the modulator and the optical switch is introduced at the transmitting end, so that the transmitting extinction ratio is remarkably improved, the direct-current leakage interference caused by the non-working ONU is effectively suppressed, and the signal-to-noise ratio and the receiving sensitivity of the system are improved. Meanwhile, the combination of the simplified receiving architecture and the silicon photon platform realizes the transceiving function with low power consumption, low cost and small volume, and can meet the requirements of a high-speed optical access scene.

A non-degenerate mode few-mode multiplexer / demultiplexer based on a four-core transmission main channel is characterized in that a transmission channel of the mode division multiplexer / demultiplexer is composed of an elliptical four-core super-mode fiber core FEC-SFC and three single-mode fiber cores, the elliptical four-core super-mode fiber core at the coordinate center serves as the transmission main channel, and the single-mode fiber cores SMF1, SMF2 and SMF3 are transmission coupling channels; the length of the transmission main channel FEC-SFC is 3.588 mm, and the lengths of the SMF1, the SMF2 and the SMF3 are respectively 3.588 mm, 1.658 mm and 1.808 mm; the mode field characteristics in the optical fiber can be changed by reasonably setting parameters such as the position, the size and the refractive index distribution of the fiber core; according to the ultra-mode fiber core, the advantages of a pure silicon dioxide fiber core, an elliptical core and an ultra-mode fiber core are fused, the mode degeneracy of LP11a / LP11b is broken, four ultra-mode multiplexing and demultiplexing of LP01, LP11a, LP11b and LP21b are achieved, the refractive index fiber core made of pure silicon dioxide is adopted, and the low-loss performance is achieved; a transmission channel with a large effective refractive index difference is adopted, and the position and the length of the transmission channel are reasonably set, so that the low-crosstalk and high-extinction-ratio performance is realized, and the low-crosstalk and high-extinction-ratio optical fiber can be used for MIMO-FREE operation.

The present application relates to the technical field of flexible touch screen detection, and specifically discloses a flexible touch screen polarization characteristic detection method based on multi-modal data fusion. The method comprises the following steps: building a multi-parameter measurement optical path system, collecting speckle characteristic data, interferometric polarization phase information data and spectral characteristic data after the flexible touch screen is transmitted; generating a multi-modal fusion feature vector through time-space alignment and feature extraction; constructing a CNN-LSTM hybrid neural network model; dynamically adjusting the parameters of the CNN-LSTM hybrid neural network model by using an adaptive algorithm; inputting the multi-modal fusion feature vector into the adjusted CNN-LSTM hybrid neural network model, and outputting the polarization degree, the extinction ratio and the polarization axis direction parameters. Through the multi-parameter measurement optical path system cooperative detection, the multi-modal data fusion and the adaptive algorithm, the present application solves the polarization characteristic drift problem caused by the deformation of the flexible screen, and significantly improves the detection accuracy and stability.

The application discloses a Brewster window stack polarization modulation device. The device comprises a Brewster window stack assembly, a clamping assembly, and an installation base. The Brewster window stack assembly comprises a plurality of optical window pieces arranged in parallel and at intervals, and the included angle between the surface normal and the incident light is a Brewster angle. The installation base has a vertical part and a horizontal part. The clamping baffle is arranged opposite to the vertical part of the installation base at intervals. The optical window pieces and the gaskets are alternately arranged in parallel at intervals. One adjusting screw is arranged on each side of the installation base. The adjusting screw passes through the clamping baffle and each gasket in sequence, and is screwed with the vertical part of the installation base. The rotation of the adjusting screw is converted into the linear motion of the clamping baffle along the support surface, so as to change the distance between the clamping baffle and the vertical part and / or realize the clamping and fixing of the Brewster window stack assembly. The device can realize linearly polarized light output with high extinction ratio and high stability in a wide range of incident angles and spectral bands.

Embodiments of the present application provide a method for obtaining optical signal and related equipment, which can amplify the optical power of the output optical signal and improve the extinction ratio. The method comprises: a laser sends an initial optical signal to a modulator according to an initial electrical signal; the modulator modulates the initial optical signal to generate a first modulated optical signal under the action of a first modulated electrical signal; the modulator sends the first modulated optical signal to an optical amplifier; the optical amplifier modulates the first modulated optical signal and amplifies the optical power under the action of a second modulated electrical signal to obtain a second modulated optical signal, the time delay difference between the first modulated electrical signal and the second modulated electrical signal is less than or equal to a preset threshold, and the modulation rates of the first modulated electrical signal and the second modulated electrical signal are equal.