34results about How to "Increase absorption length" patented technology

Active pixel sensors are defined on double silicon on insulator (SOI) substrates such that a first silicon layer is selected to define radiation detection regions, and a second silicon layer is selected to define readout circuitry. The first and second silicon layers are separated by an insulator layer, typically an oxide layer, and the layers can be independently doped. Doping can be provided in the silicon layers of the SOI substrate during assembly of the SOI substrate, or later during device processing. A semiconductor substrate that supports the first and second layers can be removed for, for example, back side radiation detection, using a second insulator layer (typically an oxide layer) as an etch stop.

The invention provides a back lighting type photodiode receiving chip and a manufacturing method thereof. The chip comprises an epitaxial layer, the epitaxial layer comprises a P-shaped table face, an N-shaped table face and an indium phosphide substrate; the P-shaped table face comprises an InGaAs absorbing layer, an InGaAsP gradient layer, a reflective mirror layer, an indium phosphide top layer and an InGaAs contact layer; the N-shaped table face comprises an indium phosphide buffer layer; the indium phosphide buffer layer, the InGaAs absorbing layer, the InGaAsP gradient layer, the reflective mirror layer, the indium phosphide top layer and the InGaAs contact layer are grown on the indium phosphide substrate in sequence; an integrated micro lens is arranged at one side of the indium phosphide substrate, and the integrated micro lens and the indium phosphide buffer layer are at the different sides of the indium phosphide substrate. According to the back lighting type photodiode receiving chip and a manufacturing method, on the condition of guaranteeing that chip diffused source area keeps constant, the light absorption area of the chip is expanded, the problem of low coupling efficiency caused by small chip diffused source area is solved, and through the addition of the reflective mirror layer, the quantum efficiency of the chip can be improved.

The invention discloses a method for preparing a wave absorbing material from magnetic fluid, and belongs to the field of a wave absorbing material. The wave absorbing material is composed of a composite material coating and a semiconductor coating; the magnetic fluid which is highly stable is prepared by preparing Fe3O4 magnetic nanoparticles by adopting a chemical coprecipitation method, and ultrasonically dispersing a proper amount of surfactant in base carrier liquid; the composite material coating is prepared by uniformly mixing epoxy resin, nickel carbonyl powder and the magnetic fluid so as to obtain a mixture I, and coating n aluminum alloy sheet with the mixture I under the action of an external magnetic field; the semiconductor coating is prepared by uniformly mixing epoxy resin and silicon carbide powder so as to obtain a mixture II, and coating the composite material coating with the mixture II. According to the method disclosed by the invention, the magnetic fluid is cured on the surface of substrate under the action of the external stable magnetic field after a magnetic cone is formed, so as to greatly increase absorption length and widen the absorption band. Meanwhile, the wave absorbing material prepared by adopting the method disclosed by the invention has the advantages of light weight, low thickness and the like, and is convenient in industrial production on a large scale.

The invention provides an aircraft fire alarm detection device and method based on CO2 gas concentration monitoring. A dual-wavelength infrared monitoring principle and a diffusion type structure are adopted, based on the continuous monitoring of the concentration of CO2 gas of an aircraft in flight in a low-temperature low-pressure environment, the fire alarm detection of an aircraft is carried out; the detection device and method have the advantages of capability of being adaptive to a low-temperature low-pressure atmospheric environment, heating, preserving heat, monitoring continuously online in a constant-temperature state, rapid response, high reliability, excellent waterproof and dustproof performances, no need of using an air pump, and the like, and can be widely applied to aircraft fire alarm detection systems. A dual-channel infrared detector is adopted for eliminating interferences caused by factors of light source instability and the like; a light reflection lens is adopted for lengthening the absorption length of infrared light; a heating element and a heat preservation material are adopted for reinforcing the environment adaptability; a conical light concentrator is adopted for increasing the received light intensity and compensating and correcting the temperature and air pressure automatically, so that the aircraft fire alarm detection reliability is improved effectively. The device and the method guarantee the rapidness and accuracy of aircraft fire disaster alarming.

The invention discloses a silicon nanowire grating resonant enhanced photoelectric detector, which comprises a silicon substrate, a silicon oxide layer, an I-shaped mesa structure, a protective layer, a metal gate electrode and two photocurrent output metal electrodes, wherein the silicon oxide layer is manufactured on the silicon substrate; the I-shaped mesa structure is manufactured on the silicon oxide layer, two ends of the I-shaped mesa structure are provided with a P-type electrode and an N-type electrode, and a silicon nanowire grating resonant cavity structure is connected between theP-type electrode and the N-type electrode; the protective layer is manufactured on the surface and side faces of the I-shaped mesa structure, and electrode windows are formed on the P-type electrode and the N-type electrode at two ends of the I-shaped mesa structure; the metal gate electrode is manufactured on the protective layer of the silicon nanowire grating resonant cavity structure and is close to one side of the N-type electrode; and the two photocurrent output metal electrodes are manufactured in the electrode windows of the protective layer on the P-type electrode and the N-type electrode of the I-shaped mesa structure.

The invention provides a hydrocarbon combustible gas leakage monitoring device and a method based on network transmission. The device is an integrity formed by an infrared source (1), a collecting lens (2), a thermal detector (3), a tapered optical collector (4), a measuring optical filter (5), a reference optical filter (6), a two-channel infrared detector (7), a reflecting mirror (8), a reflecting mirror base (9), a support (10), a filter protective cover (11), a water-proof dust-proof gas-permeable membrane (12) and a circuit board (13). According to the device, a double wavelength infrared monitoring principle is utilized, a reasonable structural design is assisted, self temperature compensation and network output function are achieved, the monitoring accuracy is high, the device is stable and reliable, and the device meets the requirements of hydrocarbon combustible gas leakage monitoring based on the network transmission.

The invention provides a composite structure type laser amplifier. The composite structure type laser amplifier comprises a wedge-shaped laser slice coupler 3 and a wedge-shaped laser slice 1 used as a gain medium, wherein the wedge-shaped laser slice 1 and the wedge-shaped laser slice coupler 3 are both thin-long slices, and the longitudinal sections thereof are of isosceles trapezoid; the thick-end end planes of the wedge-shaped laser slice 1 and the wedge-shaped laser slice coupler 3 are coaxially spliced; and meanwhile, the thin-end end plane of the wedge-shaped laser slice coupler 3 receives an incident pumping laser beam, and the wedge-shaped laser slice coupler 3 couples the pumping laser beam to the wedge-shaped laser slice 1. According to the composite structure type laser amplifier, pumping light is incident from the thin-end end plane of the wedge-shaped laser slice coupler, so that pumping light absorption can be more uniform and coupling efficiency of the pumping light can be improved; the light is internally and totally reflected on boundary of the wedge-shaped laser slice, so that the absorption length of the absorbed light is prolonged and the wedge-shaped laser slice is uniformly pumped.

The invention discloses a solar cell with a phase grating nanostructure. A transmission type phase grating is manufactured on the surface of the solar cell, wherein the phase grating is composed of a series of etching grooves, the depth of the etching grooves is calculated through the formula h=lambda / [2(n-1)], pi represents the phase difference generated when incident light is spread to the lower surface from the upper surface of the grating, lambda represents the central wavelength of the incident light, and n represents the refractive index of materials of the phase grating on the surface of the solar cell. The width and interval of the etching grooves are designed according to the Huygens-Fresnel principle and calculated through the Fresnel wave band method. By means of the integration of the phase grating and the solar cell, a high-performance, small-size and high-efficiency photovoltaic system is obtained. The reflectivity of the surface of the solar cell can be effectively decreased. The absorption length of photons in PN junction areas of the solar cell is effectively increased. The light field density of the incident light in the PN junction areas of the solar cell is effectively increased; the effective photon absorption of the PN junction areas of the solar cell is effectively increased.

An angle pump method and its solid laser gain module used in strips is to apply an angle pump structure in which the pump light source is put at the corners of the strip, so the pump light will emit into the strip from its corner plane. Center of the strip contains one or more doped areas and the surrounding linking are not doped. Most of the pump light is restricted in the strip absorbed many times due to the complete reflection, so as to get a rather long absorption length and high absorption efficiency. Strips are in the structure of doped at the center not doped around to ensure the pump light is absorbent at the strip center, reducing thermal lens effect and stress birefringence effect, avoiding strip distortion.

The invention provides a spreading type device and method for monitoring SF6 gas leakage. A device comprises an infrared light source (1), a condenser lens (2), a temperature detector (3), a conical light collection device (4), a measuring optical filter (5), a reference optical filter (6), a double-channel infrared detector (7), a reflection mirror (8), a reflection mirror seat (9), a support (10), a filter protection cover (11), a waterproof dustproof gas-permeable film (12), a signal conditioning module (13), an analog / digital (A / D) conversion module (14), a data processing module (15) and a light source driving module (16). The device and method is capable of continuously monitoring SF6 gas leakage on line, high in response and high in accuracy and reliability. The device has excellent waterproof dustproof performance, does not require a gas pump and can be widely applied to an SF6 gas leakage monitoring system.