204 results about "Spectral responsivity" patented technology

Methods for using spectrally separated light pulses to collect more LIDAR information are presented. In one embodiment, a monochromatic pulse is transmitted to collect range information and a white pulse is transmitted a short time afterwards to collect spectral responsivity information or color of the target. In another embodiment, the white light pulse is used to collect both range and spectral responsivity information of the target. In another embodiment, the spectral separated laser is spatially spread in order to collect range information over more than one point at a time.

A direct detector for terahertz radiation comprises a grating-gated field-effect transistor with one or more quantum wells that provide a two-dimensional electron gas in the channel region. The grating gate can be a split-grating gate having at least one finger that can be individually biased. Biasing an individual finger of the split-grating gate to near pinch-off greatly increases the detector's resonant response magnitude over prior QW FET detectors while maintaining frequency selectivity. The split-grating-gated QW FET shows a tunable resonant plasmon response to FIR radiation that makes possible an electrically sweepable spectrometer-on-a-chip with no moving mechanical optical parts. Further, the narrow spectral response and signal-to-noise are adequate for use of the split-grating-gated QW FET in a passive, multispectral terahertz imaging system. The detector can be operated in a photoconductive or a photovoltaic mode. Other embodiments include uniform front and back gates to independently vary the carrier densities in the channel region, a thinned substrate to increase bolometric responsivity, and a resistive shunt to connect the fingers of the grating gate in parallel and provide a uniform gate-channel voltage along the length of the channel to increase the responsivity and improve the spectral resolution.

A series of optical spectral sensors is based on a combination of solid-state sources (illumination) and detectors housed within an integrated package that includes the interfacing optics and acquisition and processing electronics. The focus is on low cost and the fabrication of the sensor is based on techniques that favor mass production. Materials and components are selected to support low-cost, high volume manufacturing of the sensors. Spectral selectivity is provided by the solid-state source(s) thereby eliminating the need for expensive spectral selection components. The spectral response covers the range from the visible (400 nm) to the mid-infrared (25,000 nm/25.0 μm), as defined by the availability of suitable low-cost solid-state source devices. A refractive optical system is employed, primarily in an internal reflection mode, allowing a selection of sample handling tools, including, but not restricted to internal reflectance and transmittance. A secondary channel allowing for light scattering or fluorescence methods is an option. The targeted applications of the sensing devices are for lubricants and functional fluids in the heavy equipment, automotive and transportation industries. A source reference channel is included to provide measurement stability and temperature compensation.

The invention discloses an optical detector based on two-dimensional stratiform atomic crystal materials. The optical detector comprises a silicon substrate coated with silica, a first graphene conducting layer, a two-dimensional stratiform atomic crystal semiconductor material layer and a second graphene conducting layer are sequentially coated on the silicon substrate coated with the silica in a superposition mode, and the first graphene conducting layer and the second graphene conducting layer respectively form heterogeneous structures with the two-dimensional stratiform atomic crystal semiconductor material layer. One end of the first graphene conducting layer and one end of the second graphene conducting layer are provided with a first electrode layer and a second electrode layer respectively, and the first electrode layer and the second electrode layer have no any overlapping, and the first electrode layer and the second electrode layer are arranged outside an overlapping area of the first graphene conducting layer, the second graphene conducting layer and the two-dimensional stratiform atomic crystal semiconductor material layer at the same time. A passivation layer is respectively arranged above each layer. The optical detector based on the two-dimensional stratiform atomic crystal materials utilizes the two-dimensional stratiform atomic crystal materials, has the operating characteristics that detection spectrum range is wide, response speed is fast and cut-off frequency is high, and has the characteristics that spectral responsivity of a device is high and extraction of a photon-generated carrier is simple.

A detector system, filter therefor, and method of making same is disclosed. The filter includes an interference element having a reflection band disposed primarily in the near infrared, and having a high transmission over most of the visible region. The filter also includes an absorptive element that absorbs light non-uniformly over the visible region. The filter when combined with a semiconductor photodiode or other suitable detector yields a detector system whose spectral responsivity closely matches the visual response of the human eye.

The invention relates to a multi-input and multi-output (MIMO) optical communication system and method. The optical communication system is formed by adopting a plurality of light sources with spectrum differences and a plurality of optical detectors with spectrum response characteristic differences, the spectrum differences of the light sources and the spectrum response differences of the optical detectors ensure that channel impact responses from light sources of all emitters to photoelectric detectors of all receivers are mutually uncorrelated, thus an MIMO channel matrix is obtained, and concentrated MIMO optical communication is realized. According to the invention, MIMO optical communication is realized in an optical fiber channel or free space channel without a complex optical device, thus optical communication rate and reliability are improved.

The invention discloses an ultraviolet radiation comprehensive test device and belongs to the field of optical tests and measurements. The device simplifies an input optical system, adds an integrating sphere and an ultraviolet irradiance standard lamp which is arranged on a second mobile platform, and correspondingly integrates the integrating sphere and an electronic shutter on a first mobile platform with the ultraviolet radiance standard lamp and a filtering component on the basis of a conventional spectral responsivity test device; the first mobile platform is in the same direction as a third mobile platform with an ultraviolet standard detector and is vertical to the second mobile platform; and all the standard lamps or the standard detector and lamps to be measured or detectors to be measured are cut into a measurement optical path under control of a data processing system so as to realize measurement and calibration of ultraviolet spectral radiance, spectral radiance illuminance and spectral responsivity. The device solves the problems of resource sharing and cost saving during ultraviolet radiation measurement, and has the characteristics of simple operation and high precision.

The invention discloses a spectral responsivity test method for a plane array detector, which belongs to the field of optical test and metering. The method is characterized in that on the basis of the spectral responsivity test method for a unit detector, the spectral responsivity of an image element in the center of the plane array detector is tested, the measurement of the space uniformity of the plane array detector is combined, and the accurate measurement on the full-wave-band spectral responsivity of the plane array detector in the whole photosensitive surface is realized. The test method solves the difficult problem of the spectral responsivity measurement of the plane array detector, the blank of the spectral responsivity measurement field of the plane array detector is filled, and in addition, the method has the characteristics that the resources are shared, the cost is saved, and the measuring efficiency is high.

The invention discloses a fiber bragg grating sensing dynamic load identification method based on AR model and mahalanobis distance. The method comprises the following steps: arranging the position of a distributed fiber bragg grating sensing network; monitoring and collecting impact response dynamic signals in real time; analyzing time domains of impact response signals and determining a response spectrum characteristic frequency capable of representing impact position information; extracting wavelet-packet-analysis-based spectrum response characteristic frequency and building an AR model parameter matrix; judging similarity between the impact position signals and response signals in a sample library of the AR model parameter matrix by using mahalanobis distance, primarily determining the area of the impact load to be monitored according to three impact positions with high similarity, then accurately identifying the impact load position by using a triangular center location method. Since a fiber bragg grating demodulating system is relatively low in demodulating frequency, the impact load cannot be located by using a time difference method; compared with the conventional time domain locating method, the method is simple and reliable.

The present invention provides an optical sensor having one or more filter-photodetector pairs and feedback to monitor the intensity and chromaticity of the white light generated by an illumination system. According to the present invention, filter-photodetectors are configured into pairs thereof, wherein a first filter-photodetector of a pair is configured and arranged so as to be sensitive to a predetermined region of the electromagnetic spectrum, while a second filter-photodetector of the pair is configured and arranged to be sensitive to a substantially complementary region of the electromagnetic spectrum. The spectral responsivity of the first filter-photodetector and the second filter-photodetector overlap in a predetermined region of the electromagnetic spectrum. Furthermore, the spectral responsivity of the first filter-photodetector is configured to substantially monotonically increase with respect to wavelength within said predetermined region, while the spectral responsivity of the second filter-photodetector is configured to substantially monotonically decrease with respect to wavelength within said predetermined region.

This invention discloses one infrared light spectrum scaling system based on detector, wherein, the light source and single color device incidence seam are fixed with wave trop device; the single color device inside is fixed with grating from exit seam into light shield box through two axis arc lens and filter slices to detector and scaling detector. This invention adopts Newport company infrared light source and Acton Research single color machine to realize light spectrum response test volume of 1 mum-12 mum.

The present invention discloses an optical device spectral response measurement method, and belongs to the microwave photon measurement technology field. The method comprises the steps of utilizing a double-sideband phase modulation method and a double-sideband amplitude modulation method to modulate a microwave swept-frequency signal on an optical carrier separately to obtain a double-sideband phase modulation signal and a double-sideband amplitude modulation signal separately; taking the double-sideband phase modulation signal and the double-sideband amplitude modulation signal as the detection signals separately, enabling the detection signals to pass a to-be-measured optical device, then carrying out the beat frequency, transforming the spectral response information of the to-be-measured optical device into an electric domain, and then utilizing an amplitude phase extraction method to extract a transmission function of the to-be-measured optical device; adding and subtracting the transmission functions of the to-be-measured optical device under the two detection signals separately to obtain a broadband transmission function of the to-be-measured optical device. The present invention also discloses an optical device spectral response measurement. The measurement device of the present invention has a wider measurement range, and can work at any wavelength.

The invention relates to a structure and a preparation method of a surface electric field enhanced PIN photoelectric detector, and belongs to photoelectric detectors. The PIN photoelectric detector is characterized in that a p-type heavily doped region 106 is selectively added in a single p-type lightly doped region 105 which originally covers the whole photosensitive surface, the p-type heavily doped region 106 is enabled to be connected with a p-type ohmic contact layer, thereby enabling a longitudinal electric field to be enhanced, improving the response speed of the detector, introducing a transverse electric field at the same time, increasing transport channels of photoproduction holes, reducing the transport resistance, reducing nonradiative recombination when the photoproduction holes are transported to an electrode in the p-type lightly doped region 105, improving the collection efficiency of the photoproduction holes, and then effectively improving the quantum efficiency. The structural design and the preparation process provided by the invention of the surface electric field enhanced PIN photoelectric detector solve a problem that a photoelectric detector with a traditional structure is low in collection efficiency for photoproduction carriers, and improve the spectral response of devices.

The present invention discloses a carbon nano tube film micromachinery infrared detector with simple structure, high resolution, broad spectrum respose range, high sensitivity and low cost, and is characterized by that it includes micromachinery with a certain backing material, pick-up circuit and micromachinery resonator on which a layer of carbon nano tube film as light emission absorbing material is grown. The absorption coefficent ela of carbon nano tube film to infrared radiation can be up to 0.98, so that it possesses high sensitivity and small noise, and the detection power of said detector also can be raised. The microresonator can be made up by using MEMS process, can be produced in alarge scale.

The invention relates to a device for measuring the spectral responsivity of an infrared photoelectric detector. Most current Fourier transform infrared spectrometers cannot be directly used for measuring the spectral responsivity of the infrared photoelectric detector. The device for measuring spectral responsivity of the infrared photoelectric detector comprises a Fourier transform infrared spectrometer which comprises a Michelson interferometer, a sample room, a first computer, an infrared photoelectric detector, a preamplifier and a second computer. The infrared photoelectric detector and preamplifier are arranged in the sample room. The arranging position of the infrared photoelectric detector ensures that the photosurface can receive the interference intensity signal emitted by the Michelson interferometer. The infrared photoelectric detector is connected with the second computer via the preamplifier and an A/D collector, and the second computer is in communication connection with the first computer. In the invention, the Fourier transform infrared spectrometer can not only be used to measure the spectral responsivity but also have the previous function of measurement.

An areal active pixel image sensor (AAPS) with programmable row-specific gain is disclosed for converting hyper-spectral light image into video output signal (VOS). The AAPS includes:

• • a) An areal active pixel sensor (APS) array each capable of photoelectrically converting and integrating an incident pixel light into a photoelectric signal through an integration time period TNT with a photoelectric signal gain GPE.
  • b) A video output signal conditioner (VOSC), coupled to the APS array, for multiplexing and amplifying the photoelectric signals into the VOS with an electric signal gain GEE.
  • c) The VOSC further programmably sets at least one of GPE and GEE to be row-specific.

Consequently, the AAPS exhibits an overall photoelectric signal gain of GOA=GPE×GEE that is row-specific and it can compensate for image signal distortion caused by non-uniform spectral response of the APS elements during hyper-spectral imaging.

The invention discloses a low-temperature absolute radiometer absolute spectral responsivity calibration method and an experimental apparatus. The experimental apparatus mainly comprises a main light path unit, a swing module unit, a low-temperature absolute radiometer, a detector vacuum chamber and a main control computer. The method includes the steps that a standard transmission detector and the low-temperature absolute radiometer are placed in the same vacuum environment and driven and controlled by an arc-shaped guide rail so that the low-temperature absolute radiometer and the standard transmission detector can pass through the same light path transmission path, the received incident light powers are completely the same, therefore, the influence of uncertainty in the process of measurement of window transmittance is eliminated, accuracy in the standard transmission process of the low-temperature absolute radiometer will be greatly improved, and the high-precision calibration of the absolute spectral responsivity of the standard transmission detector in the range between the ultraviolet band and the infrared band is achieved.

The invention discloses a wideband efficient photocatalyst Li3FeGeO5 with the visible light response function and a preparing method thereof. The chemical composition formula of the photocatalyst is Li3FeGeO5. The invention further discloses the preparing method for the material. The obtained photocatalyst has the advantages of being wide in spectrum response range, high in light conversion efficiency, good in stability and the like. Under radiation of visible light, the photocatalyst has a function of decomposing harmful chemical substances and organic biomass and an antibacterial function; in addition, the preparing method is simple, low in resultant temperature and cost, and suitable for industrial production and application.