42results about How to "Narrow spectral width" patented technology

An exposure apparatus has a laser device that is small, easy to maintain, and capable of producing an output that is unlikely to be affected by optical surges occurring in the beginning of operation. A single-wavelength laser oscillator (11) supplies a laser beam (LB1) to a fiber optic amplifier (13) through an optical modulator (12). The amplified laser beam is split by splitters (14, 16-1 to 16-m), amplified by optical amplifier units (18-1 to 18-n) and supplied through a fiber bundle (19) to a wavelength converter (20), which in turn converts the split beams into ultraviolet laser radiation (LB5) for use as exposure light. The optical modulator (12) outputs light pulses during the generation of ultraviolet light. The optical modulator (12) also produces laser radiation during the absence of ultraviolet light, but the laser radiation has substantially the same average output and a considerably low peak compared with that during the generation of ultraviolet light.

A compact mid-IR laser device utilizes an external cavity to tune the laser. The external cavity may employ a Littrow or Littman cavity arrangement. In the Littrow cavity arrangement, a filter, such as a grating, is rotated to provide wavelength gain medium selectivity. In the Littman cavity arrangement, a reflector is rotated to provide tuning. A quantum cascade laser gain medium provides mid-IR frequencies suitable for use in molecular detection by signature absorption spectra. The compact nature of the device is obtained owing to an efficient heat transfer structure, the use of a small diameter aspheric lens for both the output lens and the external cavity lens and a monolithic assembly structure to hold the optical elements in a fixed position relative to one another. The compact housing size may be approximately 20 cm×20 cm×20 cm or less. Efficient heat transfer is achieved using a thermoelectric cooler TEC combined with a high thermal conductivity heat spreader onto which the quantum cascade laser gain medium is thermally coupled. The heat spreader not only serves to dissipate heat and conduct same to the TEC, but also serves as an optical platform to secure the optical elements within the housing in a fixed relationship relative on one another. The small diameter aspheric output and external cavity lens each may have a diameter of 10 mm or less and each lens is positioned to provided a collimated beam output from the quantum cascade laser gain medium. The housing is hermetically sealed to provide a rugged, light weight portable MIR laser source.

Luminescent materials and the use of such materials in anti-counterfeiting, inventory, photovoltaic, and other applications are described herein. In one embodiment, a luminescent material has the formula: [AaBbXxX′x′X″x″][dopants], wherein A is selected from at least one of elements of Group IA; B is selected from at least one of elements of Group VA, elements of Group IB, elements of Group IIB, elements of Group IIIB, elements of Group IVB, and elements of Group VB; X, X′, and X″ are independently selected from at least one of elements of Group VIIB; the dopants include electron acceptors and electron donors; a is in the range of 1 to 9; b is in the range of 1 to 5; and x, x′, and x″ have a sum in the range of 1 to 9. The luminescent material exhibits photoluminescence having: (a) a quantum efficiency of at least 20 percent; (b) a spectral width no greater than 100 nm at Full Width at Half Maximum; and (c) a peak emission wavelength in the near infrared range.

A compact mid-IR laser device utilizes a quantum cascade laser to provide mid-IR frequencies suitable for use in molecular detection by signature absorption spectra. The compact nature of the device is obtained owing to an efficient heat transfer structure, the use of a small diameter aspheric lens and a monolithic assembly structure to hold the optical elements in a fixed position relative to one another. The compact housing size may be approximately 20 cm×20 cm×20 cm or less. Efficient heat transfer is achieved using a thermoelectric cooler TEC combined with a high thermal conductivity heat spreader onto which the quantum cascade laser is thermally coupled.

Luminescent materials and the use of such materials in anti-counterfeiting, inventory, photovoltaic, and other applications are described herein. In one embodiment, a luminescent material has the formula: [AaBbXxX′x′X″x″][dopants], wherein A is selected from at least one of elements of Group IA; B is selected from at least one of elements of Group VA, elements of Group IB, elements of Group IIB, elements of Group IIIB, elements of Group IVB, and elements of Group VB; X, X′, and X″ are independently selected from at least one of elements of Group VIIB; the dopants include electron acceptors and electron donors; a is in the range of 1 to 9; b is in the range of 1 to 5; and x, x′, and x″ have a sum in the range of 1 to 9. The luminescent material exhibits photoluminescence having: (a) a quantum efficiency of at least 20 percent; (b) a spectral width no greater than 100 nm at Full Width at Half Maximum; and (c) a peak emission wavelength in the near infrared range.

A compact mid-IR laser device utilizes an external cavity to tune the laser. The external cavity may employ a Littrow or Littman cavity arrangement. In the Littrow cavity arrangement, a filter, such as a grating, is rotated to provide wavelength gain medium selectivity. In the Littman cavity arrangement, a reflector is rotated to provide tuning. A quantum cascade laser gain medium provides mid-IR frequencies suitable for use in molecular detection by signature absorption spectra. The compact nature of the device is obtained owing to an efficient heat transfer structure, the use of a small diameter aspheric lens for both the output lens and the external cavity lens and a monolithic assembly structure to hold the optical elements in a fixed position relative to one another. The compact housing size may be approximately 20 cm×20 cm×20 cm or less. Efficient heat transfer is achieved using a thermoelectric cooler TEC combined with a high thermal conductivity heat spreader onto which the quantum cascade laser gain medium is thermally coupled. The heat spreader not only serves to dissipate heat and conduct same to the TEC, but also serves as an optical platform to secure the optical elements within the housing in a fixed relationship relative on one another. The small diameter aspheric output and external cavity lens each may have a diameter of 10 mm or less and each lens is positioned to provided a collimated beam output from the quantum cascade laser gain medium. The housing is hermetically sealed to provide a rugged, light weight portable MIR laser source.

An exposure apparatus has a light source comprising a laser device that is small and easy to maintain. The laser device comprises a laser oscillator for generating a single-wavelength laser beam (LB3) within a wavelength range including infrared and visible regions; an optical amplifier (18) for amplifying a laser beam (LB3); and a wavelength converter for converting the amplified laser beam into ultraviolet light using a nonlinear optical crystal. The optical amplifier (18) includes a plurality of stages of optical fiber amplifiers (22, 25) for sequential amplification of the laser beam (LB3), and a narrow-band filter (24A) and an isolator (IS3) arranged between optical fiber amplifiers.

A laser apparatus that includes a laser light generation section, an optical amplification section, a wavelength conversion section and a suppressing section is provided. The laser light generation section includes a single wavelength oscillatory laser and generates pulsed light having a single wavelength within a wavelength range ranging from about 1.51 to 1.59 μm. The optical amplification section includes an optical fiber amplifier and is optically connected to the laser light generation section to amplify the pulsed light. The wavelength conversion section includes a nonlinear optical crystal and is optically connected to the optical amplification section to perform wavelength conversion of the amplified pulsed light into ultraviolet light. The suppressing section suppresses expansion of a wavelength width of light originated in a nonlinear effect of an optical element between the single wavelength oscillatory laser and the wavelength conversion section.

A compact mid-IR laser device utilizes a quantum cascade laser to provide mid-IR frequencies suitable for use in molecular detection by signature absorption spectra. The compact nature of the device is obtained owing to an efficient heat transfer structure, the use of a small diameter aspheric lens and a monolithic assembly structure to hold the optical elements in a fixed position relative to one another. The compact housing size may be approximately 20 cm×20 cm×20 cm or less. Efficient heat transfer is achieved using a thermoelectric cooler TEC combined with a high thermal conductivity heat spreader onto which the quantum cascade laser is thermally coupled. The heat spreader not only serves to dissipate heat and conduct same to the TEC, but also serves as an optical platform to secure the optical elements within the housing in a fixed relationship relative on one another. A small diameter aspheric lens may have a diameter of 10 mm or less and is positioned to provided a collimated beam output from the quantum cascade laser. The housing is hermetically sealed to provide a rugged, light weight portable MIR laser source.

The invention discloses a multi-point on-line detection device for coal mine gas based on spectral absorption, and relates to a coal mine gas detection device, in particular to a multi-point on-line CH4 concentration monitoring device based on a characteristic absorption line of methane (CH4) near a near infrared band 1653nm. The device comprises a D / A conversion module, a DFB laser, a 1*N optical splitter, an open air chamber group, a reference air chamber, a photodetector group, a preamplifier group, an electronic switch, a band-pass filtering circuit, a first phase-locked amplification circuit, a second phase-locked amplification circuit, a first A / D conversion module, a second A / D conversion module, a first DDS, a second DDS, a third DDS, an MCU, a display, a serial port, and a computer. Compared with the prior methane gas monitoring device, the device has the advantages of higher sensitivity, higher gas identification ability, quick response ability, extremely strong anti-jamming ability, easy network formation, and so on, so the device is a gas monitoring device which is most suitable to be used underground at present.

A high power diode laser system utilizes an external cavity to narrow the spectral width of a high power multimode diode laser to change the output power normally produced by the diode from a broad spectrum to a very narrow spectrum. The power output of the laser system is concentrated over a narrow spectral range which falls within the useable range for particular applications, such as optical pumping of noble gas samples for magnetic resonance imaging. The output of the diode is received by a collimating element which directs the light on a beam path to a diffraction grating which is oriented at an angle to the incident beam. A portion of the beam may be directed from the diffraction grating to provide useable output light, and a portion of the light incident on the grating is directed back to be focused on the diode to provide feedback to cause the diode to preferentially lase at the wavelength of the light that is fed back. A polarization rotation element may be used to orient the polarization of the light passing through it to control the amount of feedback light.

The invention belongs to the field of quantum private communication and specifically relates to a single photon source based on a Faraday-Sagnac loop and a realization method thereof. The single photon source is characterized in that a system of the single photon source includes a laser device, a circulator, a polarization analyzer and the Faraday-Sagnac loop which includes a four-port optical-fiber beam splitter, a phase modulator and a Faraday rotating mirror. Continuous light output by the laser device enters the four-port optical-fiber beam splitter via the circulator. The four-port optical-fiber beam splitter divides the continuous light into two beams of orthogonal-linear polarized light, which are identical in amplitude and phase. The two beams of linear polarized light are transmitted in opposite directions along the Faraday-Sagnac loop and modulated by the phase modulator at different moments. The two beams of modulated linear polarized light are overlaid in the four-port optical-fiber beam splitter and then enter the polarization analyzer after being coupled by the circulator. The advantages of the single photon source based on the Faraday-Sagnac loop are that generated light pulses have a high extinction ratio and a narrow spectral width so that polarization dispersion of the light pulses which are transmitted in a long-distance optical fiber is reduced.

A light source apparatus includes an optical resonator formed by an optical amplification medium and an optical switch. The optical switch includes a saturable absorber and changes its transmittance or reflectance when receiving an optical pulse emitted from a light irradiation source which includes a wavelength-tunable light source. The light source apparatus emits amplified light from the optical resonator in correspondence with the center wavelength of the optical pulse from the wavelength-tunable light source. The relationship between a length L and an effective refractive index n of the optical resonator and a repetition frequency f of the optical pulse satisfies a condition L<c / (nf), and a relationship between the length L and a recovery time τ in which the changed transmittance or reflectance of the optical switch recovers satisfies a condition τ>(nL) / c.

An integrated swept wavelength tunable optical source uses a narrowband filtered broadband signal with an optical amplifier and self-tracking filter. This source comprises a micro optical bench, a source for generating broadband light, a tunable Fabry Perot filter, installed on the bench, for spectrally filtering the broadband light from the broadband source to generate a narrowband tunable signal, an amplifier, installed on the bench, for amplifying the tunable signal. The self-tracking arrangement is used where a single tunable filter both generates the narrowband signal and spectrally filters the amplified signal. In some examples, two-stage amplification is provided. The use of a single bench implementation yields a low cost high performance system. For example, polarization control between components is no longer necessary.

An organic electroluminescence device, includes a substrate; an anode layer; an organic layer including at least one organic material having a fluorescence spectrum; and a cathode layer, wherein the organic electroluminescence device has a primary light outgoing direction that is parallel to a surface of the substrate, wherein the organic electroluminescence device has an optical waveguide that includes a core layer formed by the anode layer and the organic layer, and a clad layer formed by the substrate and the cathode layer, and wherein the optical waveguide has cutoff wavelengths in a transverse electric mode any one of which is within a wavelength range of a full width at half maximum of the fluorescence spectrum of any one of the organic materials included in the organic layer.

The invention provides a display panel, a manufacturing method thereof and a display device, and relates to the technical field of display. A light emitting device layer is arranged on a driving backboard, a packaging layer, a color film layer and a light absorption layer are arranged on the side, away from the driving backboard, of the light emitting device layer, and the light absorption layer is configured to absorb light with the specific wavelength in external environment light and light emitted by the light emitting device layer; and the specific wavelength includes at least one of a wavelength between the red light band and the green light band, a wavelength between the green light band and the blue light band, and at least one of a wavelength less than the blue light band, and a wavelength greater than the red light band. The absorption layer is added in the display panel, and the light absorption layer absorbs light with a specific wavelength in external ambient light and light emitted by the light emitting device layer, so that the spectral width of the light emitted from the light emitting surface of the display panel is narrowed, and the color purity of the light emitted from the light emitting surface of the display panel is improved; therefore, the display effect of the display panel is improved.

The invention discloses a passive optical network and an optical module of an optical network unit thereof. The passive optical network comprises an OLT (Optical Line Terminator), a first WDM (Wavelength Division Multiplexing), a second WDM and a plurality of ONU (Optical Net Unit) optical modules, wherein a laser emission unit in each ONU optical module comprises a CML (Chirp Managed Laser) laser device and a driving circuit of the laser emission unit; the driving circuit of the laser emission unit is used for receiving an electric signal sent by ONU system equipment and driving the CML laser device to emit an optical signal with a specific wavelength according to the received electric signal; the wavelengths of the optical signals emitted by different ONU optical modules are different; and the OLT comprises a plurality of laser receiving units which are respectively used for receiving the optical signal in each wavelength, converting the received optical signal into the electric signal and then sending to a switch. The CML laser device adopted in the ONU optical modules has better spectral characteristics, so that a channel interval is reduced and the purposes of supplying more uplink channels and increasing system bandwidth are achieved.

An integrated swept wavelength tunable optical source uses a narrowband filtered broadband signal with an optical amplifier and self-tracking filter. This source comprises a micro optical bench, a source for generating broadband light, a tunable Fabry Perot filter, installed on the bench, for spectrally filtering the broadband light from the broadband source to generate a narrowband tunable signal, an amplifier, installed on the bench, for amplifying the tunable signal. The self-tracking arrangement is used where a single tunable filter both generates the narrowband signal and spectrally filters the amplified signal. In some examples, two-stage amplification is provided. The use of a single bench implementation yields a low cost high performance system. For example, polarization control between components is no longer necessary.

A transmitter of digital data includes a modulator with an input for a carrier signal and an input for a first stream of control symbols. The modulator modulates the carrier signal with a second stream of symbols produced by the modulator. Each symbol of the second stream has a value that corresponds to a sum of the present control symbol and the last K first symbols of the first stream. The integer K is greater than one.

The invention discloses an insect phototaxis testing device, which consists of an LED light source lamp tube, a power control box and a phototatic reaction box. The phototatic reaction box is divided into four areas including a dark chamber, a first phototatic channel, a second phototatic channel and a phototatic chamber via two partition boards, light intensity of a phototatic path from an insect box of the dark chamber to a light source is gradually and continuously increased, and the process of field insects trending to a trapping light source from a far region to a near region in a natural night environment can be simulated conveniently. The insect phototaxis testing device resolves the problem that a present insect phototaxis testing device is low in practicality, expensive in price or cheap in price but poor in practicality, and simultaneously difficult to carry out parallel comparison tests. Compared with the prior art, the insect phototaxis testing device has the advantages of low cost, high practicality, large spectrum selection range, more spectrum wave crests, high standardization degree, capability of carrying out comparison tests, and the like.

A narrow band laser apparatus may include: a laser resonator; a pair of discharge electrodes; a power supply; a first wavelength measurement device configured to output a first measurement result; a second wavelength measurement device configured to output a second measurement result; and a control unit. The control unit calibrates the first measurement result, based on a difference between the second measurement result derived when the control unit controls the power supply to apply a pulsed voltage to the pair of discharge electrodes with a first repetition frequency and the second measurement result derived when the control unit controls the power supply to apply the pulsed voltage to the pair of discharge electrodes with a second repetition frequency, the second repetition frequency being higher than the first repetition frequency.

Luminescent materials and methods of forming such materials are described herein. In one embodiment, a luminescent material has the formula: [AaSnbXxX′x′X″x″], where the luminescent material is polycrystalline; A is included in the luminescent material as a monovalent cation; X, X′, and X″ are selected from fluorine, chlorine, bromine, and iodine; a is in the range of 1 to 5; b is in the range of 1 to 3; a sum of x, x′, and x″ is in the range of 1 to 5; and at least X′ is iodine, such that x′ / (x+x′+x″)≧⅕.

Luminescent materials and methods of forming such materials are described herein. In one embodiment, a luminescent material has the formula: [AaSnbXxX′x′X″x″][dopant], wherein A is included in the luminescent material as a monovalent cation; X, X′, and X″ are selected from fluorine, chlorine, bromine, and iodine; a is in the range of 1 to 5; b is in the range of 1 to 3; a sum of x, x′, and x″ is a+2b; and at least X′ is iodine, such that x′ / (a+2b)≧⅕.

The invention discloses a laser emission module for lidar, which is characterized in that a semiconductor laser chip in the module is a horizontal cavity surface emitting laser (HCSEL) chip, and the laser light emitting by the HCSEL chip is collimated in at least one direction, so that the optical system is simplified; the laser emission module is enabled to have the characteristics of small central wavelength range, narrow spectral width, small wavelength temperature drift and the like without adding any optical devices through grating mode locking, and the HCSEL can simultaneously have a large light emitting area and a high-quality beam, thereby achieving the laser characteristics of high power, high brightness and uniform beam, and being very suitable for the application of long-distance and high-precision lidar. In addition, the power density of the light emitting surface is reduced due to the large light emitting area, and the life of the device is correspondingly prolonged. The laser chip structure and light emitting mode of the HCSEL can also reduce the chip cost and facilitate the integration with other optical devices in the module.

A semiconductor laser according to the present invention comprises: a substrate; an n-cladding layer disposed on the substrate; an active layer disposed on the n-cladding layer; a p-cladding layer disposed on the active layer and forming a waveguide ridge; and a diffraction grating layer disposed between the active layer and the n-cladding layer or the p-cladding layer and including a phase shift structure in a part of the diffraction grating layer in an optical waveguide direction. The width of the p-cladding layer is increased in a portion corresponding to the phase shift structure of the diffraction grating layer.

A semiconductor laser according to the present invention comprises: a substrate; an n-cladding layer disposed on the substrate; an active layer disposed on the n-cladding layer; a p-cladding layer disposed on the active layer and forming a waveguide ridge; and a diffraction grating layer disposed between the active layer and the n-cladding layer or the p-cladding layer and including a phase shift structure in a part of the diffraction grating layer in an optical waveguide direction. The width of the p-cladding layer is increased in a portion corresponding to the phase shift structure of the diffraction grating layer.

The present invention provides a method for narrowing a spectral width that can also be adapted to an ultrashort optical pulse emitted from a wavelength tunable light source, and that can provide an output optical pulse with a narrow spectral width and a low noise component, and an optical element and a light source device that use the method for narrowing a spectral width. The method includes using an optical waveguide member (2) to cause a soliton effect in an input optical pulse (1) within the optical waveguide member (2), thereby narrowing a spectral width of the input optical pulse (1) to provide an output optical pulse (3), the optical waveguide member (2) having dispersion characteristics such that the average of a second-order dispersion value (β2) with respect to the input optical pulse (1) is negative, and the absolute value of the second-order dispersion value (β2) increases in a propagation direction of the input optical pulse (1).

A visible light communication intensity-enhanced receiving system of the invention comprises a visible light illumination and communication transmitting unit, a transmitting antenna, a receiving focusing lens, a passive light conversion material, a narrow-band filter, a light amplifier, a photoelectric detector, and a signal processing unit. The visible light illumination and communication transmitting unit loads modulation information on a light source, and transmits modulated information via the transmitting antenna to a free space. The receiving focusing lens collects visible light signals. When the collected visible light signals pass through the passive light conversion material, received visible light energy is compressed and converted into a narrow spectrum in a concentrated manner. The compressed spectrum is filtered by the narrow-band filter at the focal plane of the receiving focusing lens and sent to the light amplifier for narrow spectrum amplification. The amplified narrow spectrum is converted by the photoelectric detector into electrical signals. Finally, the electrical signals are demodulated by the signal processing unit to get communication information. The system has very good application, improves the communication distance of visible light, and is practical.