899 results about "Light extinction" patented technology

An optical system (100) includes an image-collimating prism (102) having external surfaces which are associated with: a polarized source; reflective-display device (70); at least one light-wave collimating component (16) and a light-wave exit surface (20), respectively. A polarization-selective beam splitter configuration (10) is deployed within the prism (102) on a plane oblique to the light-wave entrance surface (8). The reflective-display device is illuminated by light reflected from the beam splitter configuration (10), and generates rotation of the polarization corresponding to bright regions of the image. An image from the reflective-display device (70) is selectively transmitted by the polarization-selective beam splitter configuration (10), is collimated by the collimating component (16), reflected from the polarization-selective beam splitter configuration (10) and is projected through the exit surface (20). In some implementations, an additional polarizer located at or near the exit surface helps to optimize extinction of unwanted illumination rays.

The invention discloses a laser driver and a temperature compensation circuit thereof. The temperature compensation circuit comprises a benchmark voltage generation unit, a benchmark current generation unit, a reference voltage generation unit, and a compensation current generation unit, wherein the benchmark voltage generation unit generates a benchmark voltage which increases with the increase of the temperature; the benchmark current generation unit is connected with the benchmark voltage generation unit and outputs benchmark current which increases with the increase of the benchmark voltage; the reference voltage generation unit generates a reference voltage which increases with the increase of the temperature; the compensation current generation unit is connected with the reference voltage generation unit, obtains the compensation threshold temperature according to the reference voltage, and outputs compensation current when the temperature is higher than or equal to the compensation threshold temperature; and the benchmark current and the compensation current are overlapped to form benchmark modulation current. The laser driver comprises the temperature compensation circuit and a bias current regulation circuit. An optical signal output by the laser can have constant extinction ratio by compensating modulation current of a laser through the temperature compensation circuit, and the laser can obtain steady output optical power by compensating bias current of the laser through the bias current regulation circuit.

A chiral in-fiber polarizer implemented in a chiral fiber structure having a core and a cladding surrounding the core, is provided. The chiral polarizer includes an entry end for receiving incident light and an exit end for outputting polarized light, as well as a pitch variation along its length between the entry and exit ends in accordance with a predetermined desirable pitch profile, wherein in one embodiment of the inventive polarizer, the inverse value of the chiral structure's pitch at the exit end is less than at the entry end, and preferably substantially equal to zero. The pitch profile may be advantageously selected to correspond to one or more predetermined pitch configurations, may be determined in accordance with one or more mathematical functions, or may be random. In accordance with the present invention, at least one of various parameters of the chiral structure, including, but not limited to, the core and cladding refractive indices and sizes, and the pitch profile, may be configured and selected to substantially eliminate the undesirable polarization component of the incident light by achieving an optimized extinction ratio within a desired spectral range. In another embodiment of the inventive chiral polarizer, the pitch profile is selected and configured such that the inverse value of the chiral structure's pitch at the entry end of the chiral structure is also zero. This arrangement enables significant reduction of insertion loss of the incident light entering the entry end of the inventive polarizer.

The present invention discloses an optical lens, a camera module group and an assembly method thereof. The camera module group comprises a sensitization chip and an optical lens; the optical lens includes a plurality of optical glasses, wherein the assembly position one optical glass is adjustable, and the blacking extinction processing of each optical glass is performed; and a connection part, a light beam incidence aperture and a shielding part are formed on corresponding optical glasses so as to embed and assemble each optical glass together in order, therefore parts such as a spacing ring, a diaphragm, a lens barrel structure piece and the like used in a traditional camera module group are omitted, and the manufacture precision, the yield rate and the imaging quality of the camera module group are improved.

In a Wavelength-Division-Multiplexed Passive Optical Network (WDM-PON) utilizing a conventional downstream optical signal reusing method, there is an inventory problem that different optical transmitter types need to be provided for the operation, management, replacement, etc. of a system. A WDM-PON system according to the present invention, includes: a seed light (SL) unit generating a seed light whose wavelength intervals and center wavelengths are adjusted using at least one seed light source; an optical line terminal (OLT) receiving the wavelength-multiplexed seed light from the seed light unit, transmitting a downstream optical signal to a subscriber of the WDM-PON, and receiving a upstream optical signal from the subscriber; and an optical network unit (ONU) receiving the downstream optical signal from the OLT, flattening and modulating the downstream optical signal with upstream data so that the downstream optical signal is reused for carrying upstream data. It is possible to improve the quality and reliability of downstream transmission by sufficiently increasing an extinction ratio, and improve the quality and reliability of upstream transmission by sufficiently flattening an input downstream optical signal in a semiconductor optical amplifier.

A method for separating the orthogonal polarization components of an incident optical signal into two spatially separated output ports is described. The method comprises a Mach-Zehnder interferometer where one of the two branches has a section of waveguide that exhibits form-birefringence. This integrated optic Polarization Beam Splitter (PBS) is broadband, has high extinction ratio, and has characteristics that are tunable.

Disclosed herein are methods, apparatus, and systems to achieve substantially constant optical power and / or extinction ratio for a semiconductor laser. In one aspect, a microcontroller of an optical transmitter may adjust an electrical current that is provided to a semiconductor laser based at least in part on a comparison of a first measured optical power of light emitted by the semiconductor laser and a predetermined target optical power. The microcontroller may then determine an electrical current that is capable of giving the semiconductor laser a substantially constant extinction ratio by evaluating an equation with the first measured optical power and a second optical power measured after the controller adjusts the electrical current.

An automatic closed loop power control system is described for simultaneously adjusting an output power and an extinction ratio P1 / P0 of a laser diode in order to maintain a desired average output power and a desired extinction ratio. The bias current component of a laser diode drive current is adjusted to compensate for changes in the average output power caused by ambient characteristics such as temperature and aging. Simultaneously, a modulation current component of the laser diode drive current is adjusted to maintain an extinction ratio of the laser diode output signal. The bias current and modulation current adjustments are based on the second order statistics of an average output power of the laser diode and a variance in the power output of the laser diode.

A system and method are disclosed which enable deposition parameters to be controlled in producing a metal surface to tune the localized surface plasmon resonance (LSPR) wavelength of such metal surface to a desired wavelength. For example, the surface produced may be used as an enhancement surface within a surface-enhanced spectroscopy process, wherein such surface is produced having a LSPR wavelength that provides the maximum extinction of a particular excitation light. In one embodiment, a metal is deposited onto a substrate, while controlling one or more deposition parameters to tailor the LSPR of the resulting metal surface to a desired wavelength. In one embodiment, the substrate is smooth, and does not require a mask prearranged thereon for controlling the LSPR wavelength. Rather, deposition parameters, such as temperature of the substrate, deposition rate, and film thickness may be controlled to effectively tune the LSPR wavelength of the metal surface.

The invention relates to a method for preparing polyester fibers with pearly luster. The method comprises the following steps: (1) pearlescent pigment agglomerate and full-dull PET fiber forming resin slice are blended according to the weight ratio of 5-20 to 80-95; and after drying, the water content is less than 100PPM, and the slice is delivered to a feeding port of an extruder and enters an screw extruder for heat fusing and compression; (2) the temperature is controlled to between 290 and 305 DEG C, fusant extruded out by the rotary screw rod enters a metering pump through a distributing pipe and a static mixer, delivered to a spinning component, filtered by a sea sand layer and pressed into a spinning plate to form fusant current which is cooed to form in a spinning cabinet, and the surface of a filament bundle is covered by a spinning finish; and 3. the spinning speed pre-extension is between 2, 500 and 3, 500m / min, the winding carry rate is between 5 and 15 percent for wind-forming, and the full-dull pearlescent polyester fiber POY is obtained. The manufacturing process is easily realized, and is convenient to improve the pearlescent fiber spinning effect and simultaneously provides the fibers with light extinction performance, and the pearlescent pigment has excellent performance and little feed rate.

A contact lens is provided in which tunable nanoparticles are embedded or otherwise coated on the lens to extinguish near-infrared energy. In one preferred embodiment, the tunable nanoparticles are nanoshells consisting of a dielectric core and a metal shell, wherein the plasmon resonance frequency is determined by the relative size of the core and the metal shell. With the capability to alter the relative size of the core and the metal shell, nanoshells are uniquely tunable nanoparticles, allowing a range of optical extinctions. In another embodiment, the nanoshells are tuned to extinguish energy from other parts of the energy spectrum. In one desired embodiment of the invention, these plasmon resonant structures are introduced into the lens polymer prior to formation or manufacturing of a lens. In another embodiment of the invention, these nanoshells are coated on a contact lens after formation of the lens.

Broadband optical switches based on adiabatic couplers having a pair of asymmetric waveguides with variable curvature sections include in a 2x2 configuration based on a Mach-Zehnder interferometer two such adiabatic couplers, and in a 1x2 or 2x1 configuration an adiabatic coupler and an Y-splitter. Each adiabatic coupler includes two waveguide branches of different but constant widths having curved sections with varying radii, separated over a coupling length by a changing spacing therebetween and blending in an asymmetric intersection area, and two symmetric branches. In the 2x2 switch, the two adiabatic couplers face each other with their respective symmetric branches, and are connected by the two identical arms along a main propagation axis in a mirror image. The utilization of the variable curvature adiabatic couplers in silica MZI switches on a silicon substrate provides switches with an exceptional broadband range (1.2-1.7 mum), very high extinction ratios (>35 dB), low fabrication sensitivity and polarization independent operation. The switches are significantly smaller than known broadband switches, have significantly smaller excess loss, faster switching time and low power consumption.

The invention discloses a device and a method for performing offset point automatic locking on an electrooptical modulator with ultrahigh extinction ratio. The offset point automatic locking device of the electrooptical modulator with ultrahigh extinction ratio comprises a laser, an electrooptical modulator, an optical switch, an electrooptical modulator offset voltage control system and a clock synchronization module, wherein the electrooptical modulator offset voltage control system comprises an electrooptical conversion signal amplification module, an analog-digital conversion module, a controller and an output driving circuit; and the clock synchronization module is used for opening an synchronization optical switch, inputting modulated electrical impulse of the electrooptical modulator radio-frequency end, and the disturbance leading-in time of the direct-current offset end of the electrooptical modulator. The method is characterized in that ultrahigh extinction ratio pulsed light output is realized through the cascade connection of the electrooptical modulator and the optical switch, and through controlling the offset voltage of the electrooptical modulator, the electrooptical modulator operates at an appropriate working spot stably. According to the invention, the offset voltage of the electrooptical modulator is controlled automatically; the pulsed light extinction ratio output by the device is improved greatly; and the energy is higher and much stable.

A polarized white light emitting diode provides a polarized white light to decrease glare, and increase the extinction ratio. A LED chip is disposed in a cavity between a reflection substrate and a metallic wire-grid polarizing layer, and emits a first color light. The metallic wire-grid polarizing layer is disposed under and in contact with a transparent substrate. A phosphor layer covers over the LED chip, and is disposed in the cavity with an air gap between the phosphor layer and the metallic wire-grid polarizing layer. A second color light is generated by the first color light. The metallic wire-grid polarizing layer multiply reflects a portion of first color light in plural directions in the cavity to produce secondary excitations. The polarized white light transmits through the metallic wire-grid polarizing layer by mixing a portion of first color light with the second color light excited by the first color light.

The invention discloses a two-dimensional stratified material based SOI (Semicon-on-insulator) base micro loop filter. The two-dimensional stratified material based SOI base micro loop filter comprises an SOI substrate which is formed by a buried oxide layer and top silicon; an SOI micro loop resonant cavity, input straight waveguide and output straight waveguide are arranged on the top silicon and the input straight waveguide and output straight waveguide are arranged on the upper side and the lower side of the SOI micro loop resonant cavity, so that the SOI waveguide structure is formed; two-dimensional stratified materials cover the SOI waveguide structure; two ends of the input straight waveguide are provided with input end optical grating and direct connection optical grating; one end of the output straight waveguide is provided with output end optical grating; areas of the SOI micro loop resonant cavity, which are close to the input straight waveguide and the output straight waveguide, form into a first coupling area and a second coupling area. Compared with the traditional technology, the two-dimensional stratified material based SOI base micro loop filter has the advantages of being narrow in 3dB band width, high in extinction ratio, less in noise, compatible with CMOS technology and widely applied to the on-chip optical interconnection network in the future due to the fact that the SOI base filter is further filtered due to the saturated absorption effect of two-dimensional stratified materials.

The invention relates to a cavity enhanced absorption spectrum device and method for simultaneous measurement of trace gas concentration and aerosol extinction. The LED temperature is controlled by a semiconductor refrigeration chip to ensure the stability of light intensity output. High reflectivity mirrors at both ends of an optical cavity have the same curvature radius and reflectivity greater than 99.9%, and compose a stable optical resonator. Usually, cavity enhanced absorption spectrum measures the light intensity in the cavity with or without gas absorption and the variation curve of the high reflectivity mirrors' lens reflectivity along with the wavelength, and finally the concentration of absorption gas in the cavity can be obtained. The device and the method provided by the invention can realize simultaneous measurement of trace gas concentration and aerosol extinction. The actual measured total absorption coefficient is divided into two parts, one part is a trace gas absorption structure changing rapidly along with the wavelength, and the other part is gas scattering and aerosol extinction coefficient changing slowly along with the wavelength. Nonlinear least-square fitting is carried out on the measured total absorption coefficient to calculate the concentration of the to-be-measured trace gas, and finally the gas absorption structure and gas scattering are deducted from the total absorption coefficient so as to obtain the aerosol extinction coefficient.

The invention provides a self-extinction polyurethane resin and a preparation method thereof. The resin is mainly prepared from raw materials such as polyether polyol, isocyanate, dihydric alcohol, crylic acid grafting substances, a hydrophilic chain extender, a cross-linking agent and 5-7 parts of an amino chain extender. According to the self-extinction polyurethane resin provided by the invention, as the crylic acid grafting substances which can absorb light can extinct light in a chemical manner, leather coated with the self-extinction polyurethane resin has the light extinction effect with natural color and gloss, and meanwhile through the addition of the crylic acid grafting substances, the water resistance and the solvent resistance of the self-extinction polyurethane resin are greatly improved.

The present invention discloses a method for debugging the average optical power and extinction ratio parameter of optical transmitter. The optical transmitter is set to an automatic power control mode. The modulation signal coupling mode of the laser driving chip of light transmitter and the laser is set to a direct-current coupling mode. A microcomputer tests the luminous efficiency and threshold current of laser of the optical transmitter. The microcomputer debugs the average optical power of optical transmitter to a preset average optical power area. The microcomputer debugs the present extinction ratio of optical transmitter to a preset extinction range. The technical scheme according to the invention can greatly reduce the investment of product line on the device and has the advantages of automatic debugging realization, reduced production cost and increased production efficiency.

The present invention provides a metal wire grating polarizer and a preparation method thereof, which belongs to optical devices. The object is that the present invention is of high polarized light extinction ratio, high luminous flux, simple structure and the wide range of working wavelength. The polarizer of the present invention deposits a metal aluminum nanometer wire gating on a substrate. The substrate is optical materials which are transparent from ultraviolet band to infrared band. The structure parameter of the metal aluminum nanometer wire gating is as follows: the wire gating cycle length ranges from 40 to 80 nanometers; the wire gating duty cycle is 40 percent to 60 percent; the interlayer distance is 10 to 20 nanometers. The method steps of the present invention are as follows: the substrate is cleaned; a protection film is deposited on the surface of the substrate; a photoresist is spin coated; the nanometer wire gating structure is formed on the surface of the photoresist; the nanometer wire gating structure is carved on the protection film; nanometer wire gating structure is carved on the substrate; the rest protection film is eliminated; an aluminum metal film is coated on the vertical surface of the substrate; a parallel strip nanometer wire gating is formed. The polarization extinction ratio of the wideband polarizer of the present invention can reach 33 to 37dB in the wave band range of 300 to 5000 nanometers, and the polarized light transmittance can reach 68 percent to 94 percent.

The invention provides a polarized light irradiation device for light aligning, capable of getting polarized light with excellent extinction ratio in a wavelength region less than 300nm, furthermore, in the region, transmittance will not be changed and the polarization axis will not rotates even if the incident light to the polarization element has different angles. Workpieces (4) is conveyed facing to the direction of an arrow in the view, the light from a light irradiation part (6) is polarized by a wire grid type polarization element (1) and irradiates onto the workpieces (4) which is conveyed below the light irradiation part (6) for light aligning process. The grid of the wire grid type polarization element (1) is made from titanium oxide TiOx, can obtain polarized light with a extinction ratio above 15:1 in a range of wavelength from 240nm to 300nm, and in the region with wavelength under 300nm, the transmittance will not be changed even if the incident light to the polarization element has different angles, and the polarization axis will not rotate even if the incident light to the wire grid type polarization element has different angles.

The invention discloses a monolithic integrated InGaAs line array or stacked array detector for a sub-wavelength micro-polarization grating. The detector is a photoelectric detector and consists of an InGaAs photosensitive chip, an anti-reflection film and the sub-wavelength micro-polarization grating, wherein the anti-reflection film is made of a low-refractive index SiO2 material, and the extinction ratio of the sub-wavelength micro-polarization grating is improved; the sub-wavelength micro-polarization grating is a polarization grating line array or array consisting of polarization units in different polarization orientations; and each polarization unit is a metal polarization grating of which the grating period is shorter than that of an incident light wavelength. The sub-wavelength micro-polarization grating is integrated on a chip of a near-infrared detector, and the invention has the main advantages that: (1) the polarization grating is monolithically integrated with the detector, an optical system is simplified, and motion parts of a polarization scanning system are eliminated; (2) high-accuracy angle quantification can be achieved, and an angle error is avoided; and (3) the polarization units in the different polarization orientations are imaged simultaneously, and accurate polarization information is acquired from a moving target.

The invention discloses a single-ended structure dynamic measuring Brillouin optical fiber sensing system and a sensing method. A sensing system laser light source outputs two continuous lights through a first coupler, the first continuous light enters the input end of a modulation high-extinction-ratio module, the modulation high-extinction-ratio module is connected to one input end of a second coupler; the second continuous light enters a phase shift modulating module, the phase shift modulating module is connected to the other input end of the second coupler; the second coupler is connected to the port I of an optical circulator, the port II of the optical circulator is connected with a single-ended module by the sensing optical fiber, the port III of the optical circulator is connected with a de-modulating module. By utilizing the single-ended structure, the BOTDA (Brillouin optical time domain analysis) nominal measuring distance is the effective measuring distance, the problems that the double-ended access is required in the actual measurement and the effective sensing distance is a half of the nominal sensing length existing in the prior art are solved; the extinction ratio of electro-optical modulator is improved, the measuring time is shortened, the monitoring functions of dynamic measurement and long-distance dynamic stress are realized.

The invention relates to a preparation method of waterborne polyurethane elastic dispersion. The method comprises the following steps: (1) synthesizing a siloxane polymer: polymerizing a compound as shown in formula (I) and the compound as shown in formula (II) to get the siloxane polymer; and (2) preparing the waterborne polyurethane elastic dispersion, wherein the raw material comprises the siloxane polymer obtained in the step (1). After the elastic polyurethane dispersion provided by the invention forms a film, the waterborne polyurethane elastic dispersion has not only excellent tensile strength, rebound elasticity, wear resistance, water resistance and ethanol tolerance, but also soft and smooth hand feeling and high light transmission; and an additional filler is not required, a product has high light extinction or frosted appearance by only adjusting components, after the film is formed, the elastic polyurethane dispersion is soft, and the elastic polyurethane dispersion is suitable for paper, cloth, leather and other soft substrates, and the preparation process is simple and easy to operate.

The invention provides a double-channel light cavity ring-down atmospheric aerosol extinction instrument and an extinction factor measuring method. According to the extinction instrument, utilizes a double-channel light cavity ring-down spectrum technology is applied to carry out in-situ real-time measurement on an extinction factor of atmospheric aerosol. The instrument comprises a light path system, a circuit system and a gas path system, wherein the light path system is internally provided with a first light cavity and a second light cavity, and the first light cavity and the second light cavity are utilized as double channels; and the gas path system respectively provides atmospheric gas and background atmospheric gas containing the aerosol for the first light cavity and the second light cavity, the circuit system can eliminate the transformation of the extinction factor of the aerosol caused by gas change in real time, and the extinction factor value of the atmospheric aerosol is accurately measured in a real time.

An image capturing apparatus includes an optical unit for forming an image of a subject, a first light extinction unit present on an optical axis of the optical unit and configured to adjust an amount of light by changing a dimension of a aperture stop thereof, a second light extinction unit to be present on said optical axis of the optical unit and configured to adjust an amount of light passing therethrough by changing a transmittance of the light, and a controller for controlling operations of said first and second light extinction units so as to make an exposure optimum at a time of photographing. The controller has precedence on the adjustment of the light amount with the first light extinction unit until a predetermined aperture stop diameter and has precedence on the adjustment of the light amount with the second light extinction unit in a state that the light is to be reduced beyond a state in the predetermined aperture stop diameter, thereby attaining optimization of the exposure.

The invention provides a method and a system for testing a high-speed optical module. The method comprises the steps of receiving an optical signal sent by the tested high-speed optical module, measuring the OMA (Optical Modulation Amplitude) and optical power of the optical signal, obtaining an extinction ratio by virtue of calculation, if the extinction ratio complies with the product specification, performing error code testing on the tested high-speed optical module, adopting a standard receiving tube test unit to receive an optical signal with a pseudo-random signal from the tested high-speed optical module while testing error codes, and carrying out demodulation on the optical signal by use of the standard receiving tube test unit and then carrying out comparison, thereby finishing the error rate testing.

The invention relates to a premix burner with high flame stability for use in a heat generator, preferably in the combustion chamber of a gas turbine. Modern, lean-operated premix burners enable very low noxious emissions, but sometimes operate very close to the extinction limit. To increase the stability of the lean premix combustion by increasing the distance between flame temperature and extinction limit temperature the invention proposes to equip the burner in the mixing zone (200) with a net-like structure (201) for the premixing of combustion air and fuel. According to a preferred embodiment, the net-like structure (201) consists of a plurality of layers of individual wire mesh fabrics (202) arranged at a distance from each other. The wire mesh fabrics (202) are preferably equipped with an oxidation-promoting, catalytically active surface. It was found that the net structure (201) positively influences the thermoacoustic behavior of the burner and dampens and insulates pressure waves from the combustion chamber (300), and in this way reduces the excitation of pressure waves in the combustion chamber (300).

The invention relates to the field of optical communication, in particular to the laser temperature compensation technology, and discloses a digital open loop temperature compensation system of an optical module laser device. Temperature compensation is carried out on the laser device in an optical module through a digital open loop circuit to guarantee the stable output light power and the stable extinction ratio. Meanwhile, the operating temperature, the bias currents, the backlight currents, the operating voltage and the light collection power value of the digital open loop temperature compensation system are effectively monitored in real time, the power consumption of the optical module is greatly lowered, the risk of performance deterioration and failures of the optical module at high temperature for a long time is avoided, and stable operation of the system is guaranteed. Meanwhile, hardware of the scheme is simple, the cost is lower compared with an integrated dedicated chip scheme, and production is simple and practicable.