1665 results about "Broadband light source" patented technology

Laser-based methods and systems for real-time structured light depth extraction are disclosed. A laser light source (100) produces a collimated beam of laser light. A pattern generator (102) generates structured light patterns including a plurality of pixels. The beam of laser light emanating from the laser light source (100) interacts with the patterns to project the patterns onto the object of (118). The patterns are reflected from the object of interest (118) and detected using a high-speed, low-resolution detector (106). A broadband light source (111) illuminates the object with broadband / light, and a separate high-resolution, low-speed detector (108) detects broadband light reflected from the object (118). A real-time structured light depth extraction engine / controller (110) based on the transmitted and reflected patterns and the reflected broadband light.

Integrated wired and wireless wavelength division multiplexing passive optical network (WDM PON) apparatus using a light source mode-locked to fed incoherent light includes: a fed light generator for providing fed light for up / downstream signals via a broadband light source emitting an incoherent optical signal; a central office (CO) for receiving, mode-locking, and downstream-optical-transmitting the incoherent optical signal generated by the fed light generator and receiving and optical-detecting an upstream optical signal transmitted from a subscriber unit; and the subscriber unit for receiving, mode-locking, and upstream-optical-transmitting the incoherent optical signal generated by the fed light generator and receiving and optical-detecting a downstream optical signal transmitted from the CO, wherein a wired optical transmitter for transmitting a baseband wired signal and a wireless optical transmitter for transmitting a high frequency radio frequency (RF) signal are comprised for up / downstream optical transmission of the CO and the subscriber unit.

A system for optical metrology of a biological sample comprising: a broadband light source; an optical assembly receptive to the broadband light, the optical assembly configured to facilitate transmission of the broadband light in a first direction and impede transmission of the broadband light a second direction; a sensing light path receptive to the broadband light from the optical assembly; a fixed reflecting device; a reference light path receptive to the broadband light from the optical assembly, the reference light path coupled with the sensing light path, the reference light path having an effective light path length longer than an effective light path length of the sensing light path by a selected length corresponding to about a selected target depth within the biological sample; and a detector receptive the broadband light resulting from interference of the broadband light to provide an electrical interference signal indicative thereof.

An endoscope having an optical guide that is optically coupled to a first broadband light source and a second laser light source that emits light at a wavelength in a range of 350 nm to 420 nm. The endoscope has an image sensor at a distal end and collects a reflectance image including red, green and blue components with the image sensor in response to illumination by said broadband light source. The image sensor also collects an autofluorescence image having a blue component, a green component and a red component. A processor processes the fluorescence image by determining a ratio of the fluorescence image and the reflectance image to provide a processed fluorescence image.

A method and an apparatus for noninvasively and quantitatively determining spatially resolved absorption and reduced scattering coefficients over a wide field-of-view of a food object, including fruit or produce, uses spatial-frequency-domain imaging (SFDI). A single modulated imaging platform is employed. It includes a broadband light source, a digital micromirror optically coupled to the light source to control a modulated light pattern directed onto the food object at a plurality of selected spatial frequencies, a multispectral camera for taking a spectral image of a reflected modulated light pattern from the food object, a spectrally variable filter optically coupled between the food object and the multispectral camera to select a discrete number of wavelengths for image capture, and a computer coupled to the digital micromirror, camera and variable filter to enable acquisition of the reflected modulated light pattern at the selected spatial frequencies.

PCT No. PCT / NO98 / 00031 Sec. 371 Date Jul. 29, 1999 Sec. 102(e) Date Jul. 29, 1999 PCT Filed Jan. 29, 1998 PCT Pub. No. WO98 / 36252 PCT Pub. Date Aug. 20, 1998A device for accurate and repeatable measurements of optical wavelengths, including an interrogation broadband light source (1) and a tuneable optical filter (2). A first part of the light is, in either order, transmitted through the filter (2) and reflected from, or transmitted through, at least one fibre Bragg grating (5) with known Bragg wavelength, providing an absolute wavelength reference, and directed to a first detector (7). A second part of the light is, in either order, transmitted through the filter and transmitted through, or reflected from a Fabry-Perot filter (8) with fixed and known free spectral range, creating a comb spectrum sampling the interrogation source spectrum to provide an accurate frequency / wavelength scale.

A microresonator sensor apparatus has a microcavity resonator that defines equatorial whispering gallery modes (EWGMs), whose frequencies are separated by the free spectral range (FSR). The EWGMs lie in a plane perpendicular to a microcavity resonator axis. A light source is optically coupled to inject light into the microcavity resonator. The light source produces output light having an output spectrum whose bandwidth is approximately equal to or broader than the FSR of the EGWMs. One or more fluorescent materials are excited using the excitation light coupled into the microcavity resonator. A fluorescent signal arising from fluorescence of the one or more fluorescent materials is then detected.

The invention provides a high-stability optical fiber Fabry-Perot pressure sensor packaged without glue and a manufacturing method. The sensor comprises a sensor head, a sensor body with a through-hole in middle, and an optical fiber, wherein a four-layer structure (comprising a first monocrystalline silicon piece, a first Pyrex sheet glass, a second monocrystalline silicon piece and a second Pyrex sheet glass) is adopted by the sensor head; a first reflecting surface of a Fabry-Perot cavity is formed by the back surface of the first monocrystalline silicon piece; the second monocrystalline silicon piece is used for providing a second reflecting surface of the Fabry-Perot cavity; the second Pyrex sheet glass is in butt fusion with the sensor body; and the optical fiber is fixedly arrangedin the sensor body by adopting a CO2 laser, and thereby non-glue packaging is realized. When the first layer of monocrystalline silicon piece is deformed by external pressure changes, the length of the optical fiber Fabry-Perot cavity is changed; and after a broadband light source is accessed to the sensor, the change of the cavity length can be extracted through collecting a reflection spectrum of the sensor or extracting low-coherence interference fringes of the sensor, and thereby pressure information is obtained. By adopting the structure, the influences of environmental changes such as the temperature, the humidity, and the like can be effectively eliminated, and the measurement accuracy can be greatly improved.

A spectroscopic device, which may be a handheld spectroscopic light source, which uses ambient light as a primary broadband light source, but which may be supplemented with an auxiliary light source to supplement band regions which may be deficient in the broad band source. The spectroscopic device makes use of a number of parallel control channels to monitor for sufficient light and to compensate for variations in the input light levels.

Methods and systems are provided that may be used to utilize and manufacture a light sources apparatus. A first light emitting diode emits light having a first wavelength, and a second light emitting diode for emitting light having a second wavelength. Each of the first and second light emitting diodes may comprise angled facets to reflect incident light in a direct toward a top end of the first light emitting diode. The second light emitting diode comprising angled facets may reflect incident light in a direction toward a top end of the second light emitting diode. A first distributed Bragg reflector is disposed between the top end of the first light emitting diode and a bottom end of the second light emitting diode to allow light from the first light emitting diode to pass through and to reflect light from the second light emitting diode.

A single fiber full-field optical coherence tomography (OCT) imaging probe (300) includes a hollow tube (301), and a single fiber (305) disposed within the tube for transmitting light received from a broadband light source to a beam splitter (350) in the tube optically coupled to the single fiber (305). The beam splitter (350) splits the light into a first and a second optical beam, wherein the first beam is optically coupled to a reference arm including a MEMS reference micromirror (335) which provides axial scanning and the second beam is optically coupled to a sample arm for probing a sample to be imaged. Both the reference arm and the sample ami are disposed in the tube. A photodetector array (315) is preferably disposed inside the tube (301) optically coupled to the beam splitter (350). The photodetector array (315) receives a reflected beam from the MEMS reference micromirror (335) and a scattered beam from the sample to form an image of the sample.

A fiber Bragg grating (FBG) sensor is mounted to a rotating body, which is supported by a rotating shaft mounted rotatably with respect to a fixed element. The FBG sensor extends along the rotating shaft, one end of which is disposed at the center of the end of the rotating shaft. An optical fiber is mounted to the fixed element, one end of which is disposed opposite to the end of the FBG sensor, apart from the FBG sensor. Light emitted from a broadband light source passes through the optical fiber and is transmitted to the FBG sensor across a gap between the optical fiber and the FBG sensor. The FBG sensor reflects light with frequencies corresponding to deformation of the rotating body. A data processing unit receives the reflected light and calculates the deformation of the rotating body based thereupon.

The invention discloses a magnetofluid filling photonic crystal optical fiber F-P magnetic field sensor, which belongs to the technical field of optical fiber sensing, and consists of a broadband light source 20, an optical fiber coupler 21 and optical fiber links (31, 32, 33 and 34) of the optical fiber coupler 21, a refractive index matching fluid 22, a sensor probe 23, an electromagnetic coil 18 and a current driving system 19 of the electromagnetic coil, a spectrum analyzer, a computer 24 as well as a connecting cable 26 and a connecting cable 27. The magnetofluid filling photonic crystal optical fiber F-P magnetic field sensor is characterized in that the sensor probe is formed by fusing a section of hollow photonic crystal optical fiber 12 filled with a magnetofluid 13 and a simple module optical fiber 11; the two ends of the hollow photonic crystal optical fiber are respectively stuck by a partial reflection film 14 and a total reflection mirror 15 to form an optical fiber F-P interferometric cavity structure; and the reflection rate of the magnetofluid serving as a medium in the F-P interferometric cavity is changed due to a magnetic field generated by the electromagnetic coil after conducted with a current, thereby causing the change of output spectrums so as to realize magnetic field measurement. The magnetofluid filling photonic crystal optical fiber F-P magnetic field sensor has the advantages of being low in temperature influences, simple in structure, small in size and easy to realize multi-point distribution type sense.

The invention discloses a fiber grating sensing layer-divided sinking apparatus for observing unconsolidated strata sedimentation, a data monitoring processing system, a grating sensor and an implantation method. The fiber grating sensing layer-divided sinking apparatus comprises a grating sensor and a grating sensor array, wherein the grating sensor array is used for applying a light source to the grating sensor through a broadband light source of a fiber grating demodulator and a coupler; a light signal returned by the grating sensor is input to the fiber grating demodulator through the coupler; the fiber grating demodulator is used for converting the light signal into an electric signal and calculating a center wavelength value of each grating sensor; the monitoring processing system is connected with a wavelength data acquiring module, a data analysis module, a time display wavelength module, a real-time monitoring curve module, an information prompt module, a forecasting alarm system module and the like respectively; and another path of data analysis is connected with a memory and a data processing module respectively. The device is simple in structure, not influenced by a severe environment, resistant to corrosion and electromagnetic interference, safe and reliable, convenient to use and widely applied to strata sedimentation; and sensing and transmission are integrated.

An apparatus for optical coherence tomography has a broadband light source with a short coherence length, an optical fiber that guides the light from the light source to a focusing optics, and a graded-index optics arranged between the optical fiber and the focusing optics with two opposite parallel flat sides, that is contacted on its first flat side by the optical fiber forming an irradiation point guiding light to the graded-index optics and having a pitch of N / 8, N being a natural number that cannot be divided by 4. A first structure for light reflection is arranged on the first flat side of the graded-index optics adjacent to the irradiation point, and a second structure for beam splitting is arranged on the second flat side of the graded-index optics. The focusing optics are designed for focusing the light transmitted by the second structure essentially at right angles to the flat sides of the graded-index optics.

Methods and systems for inspection of a specimen using different parameters are provided. One computer-implemented method includes determining optimal parameters for inspection based on selected defects. This method also includes setting parameters of an inspection system at the optimal parameters prior to inspection. Another method for inspecting a specimen includes illuminating the specimen with light having a wavelength below about 350 nm and with light having a wavelength above about 350 nm. The method also includes processing signals representative of light collected from the specimen to detect defects or process variations on the specimen. One system configured to inspect a specimen includes a first optical subsystem coupled to a broadband light source and a second optical subsystem coupled to a laser. The system also includes a third optical subsystem configured to couple light from the first and second optical subsystems to an objective, which focuses the light onto the specimen.

The invention provides a linear multi-wavelength confocal microscopic system, which uses more than two chromatic lenses to enable a linear incident light field to generate dispersed rays and to enable rays with different wavelengths to be focused at different positions. Moreover, the invention utilizes a linear multi-wavelength confocal microscope module with a linear scanning confocal principle and a light source dispersion technique to develop a long-field-depth high-definition optical micro-morphological profile microscopic method and a system by using a confocal microscopic technique with optical sectioning capacity and in combination with the high definition of spectral dispersion. The method and the system of the invention use a broadband light source. By adopting a dispersion objective module, the broadband light source is enabled to generate axially dispersed rays which are focused at different depths, the focused surface reflectance spectrum is obtained simultaneously, spatial filtering is conducted through a slit, the peak position of a spectral focusing response curve is accurately sensed by a linear spectral image sensing unit and thereby sectional profile measurement can be finished accurately and rapidly.

The invention discloses an optical measurement method and devices used for measuring film thickness and refractive index. Light emitted out of a broadband light source generates an interference signal through interference structure, the spectrum information of the interference signal is detected and the fourier transform of the spectrum information is carried out, thus obtaining the optical path difference information of two optical paths which can generate the interference signal. Under known refractive index, a sample is arranged in an interference arm in the same type and is measured again, and the film thickness can be obtained by comparing the information of twice optical path differences. If the refractive index is unknown, the film is required to be rotated by an angle, and the refractive index and the thickness of the film can be worked out by the measurement of a third time. The optical measurement method and the devices used for measuring film thickness and refractive index adopt an optical method and have no damage to the sample; the resolution is micro level and the measured range can achieve millimeter level. Furthermore, the sample is not required to be strictly attached onto a sample platform; meanwhile, the information processing method is simple, and the information of the thickness and the refractive index of transparent or half-transparent film can be conveniently obtained in real time.

The invention discloses a demodulating device of multi-channel high-precision fiber grating sensing and a demodulating method of the demodulating device of the multi-channel high-precision fiber grating sensing. According to the demodulating device of the multi-channel high-precision fiber Bragg grating sensing, a broadband light source, a turnable FP filter and a light amplifier are connected in series and form a turnable laser, and high-stability high-power turnable laser output is obtained. Reflected signal amplitude of a fiber bragging grating serves as dynamic feedback, and an electronic control variable optical attenuator is used for dynamically adjusting the optical power decrement corresponding to each fiber grating wavelength in real time. Therefore, a sending signal optical power with the high signal to noise ratio and the stable amplitude is obtained under the condition of each fiber grating wavelength. Unevenness of the light source and array arrangement of fiber grating sensors and unpredictable dynamic changes of the fiber grating sensors in the process of utilization are compensated compressively. Therefore, long-term detection ability and the detection precision of the fiber grating sensors are effectively improved. In addition, the demodulating device of the multi-channel high-precision fiber grating sensing and the demodulating method of the demodulating device of the multi-channel high-precision fiber grating sensing have a good application prospect in the aerospace field, in the aviation field, in the petrifaction field, in the construction field and in the power field.

A dual-port broadband light source with independently controllable output powers includes a broadband light source having a first gain medium pumped by an input pump light in order to output a first amplified spontaneous emission through both ends thereof. A second gain medium pumped by another input pump light in order to output a second amplified spontaneous emission through both ends thereof. A reflector disposed between the opposite ends of the first and second gain mediums to reflect the input first and second amplified spontaneous emissions. The first and second amplified spontaneous emissions output from the first and second gain mediums are then output to the outside through first and second output terminals.

A multi-wavelength optical transmitter which multiplexes a plurality of channels having different wavelengths into an optical signal for output includes lasers for generating mode-locked channels by corresponding incoherent light received in the lasers. The transmitter also has a semiconductor optical amplifier for amplifying, while in a gain saturation state, the optical signal multiplexed by the multiplexer / demultiplexer. Light from a broadband light source is directed by a circulator to the multiplexer / demultiplexer for demultiplexing among the lasers. Light back from the lasers is multiplexed and then directed by the circulator and amplified by a semiconductor optical amplifier for output external to the transmitter.

The invention relates to a micro-structure fiber optic Fabry-Perot cavity quasi based quasi-distributed sensor, which comprises a broadband light source (1), a fiber optic circular (2), a plurality of sensor units (3), a sensor-based optical fiber (4), an optical spectrum analyzer (5) and a data processor (6), wherein each sensor unit (3) is a micro-structure fiber optic Fabry-Perot cavity, and the sensor units are connected in series and are integrated on the sensor-based optical fiber (4); and three ports of the fiber optic ring device (2) are respectively connected with the broadband light source (1), the sensor-based optical fiber (4) integrating all sensor units, and the optical spectrum analyzer (5), and the optical spectrum analyzer (5) is connected with the data processor (6). The micro-structure fiber optic Fabry-Perot cavity quasi based quasi-distributed sensor has the advantages of large sensing capacity, simple structure, low cost, wide application prospect and the like.

The invention discloses a composite wavelength reference-based fiber bragg grating sensing demodulation device and method. The composite wavelength reference-based fiber bragg grating sensing demodulation device includes a broadband light source (1), a tunable FP filter (2), an optical fiber primary beam splitter (3), an optical fiber circulator (4), an optical fiber grating sensing array (5), a first optical fiber secondary beam splitter (61), a second optical fiber secondary beam splitter (62), an optical fiber air chamber (7), an optical fiber FP etalon (8), a notching filter (9), a photoelectric detection array (10), a data acquisition card (11) and a processing unit (12); and the composite wavelength reference-based fiber bragg grating sensing demodulation device further comprises a sensing link and a wavelength reference link. Compared with the prior art, and according to the composite wavelength reference-based fiber bragg grating sensing demodulation device and method of the invention, equal-interval reference wavelengths can be provided by the optical fiber FP etalon, and therefore, advantages of high fineness of transmission peaks, easiness in peak finding and wide wavelength coverage range can be realized; absolute reference wavelengths provided by the optical fiber air chamber are not affected by environmental factors such as temperature, vibration and impact; and stable fiber bragg grating demodulation is realized.

The invention relates to a novel optical fiber Fabry-Perot pressure sensor and a fabrication method thereof. The optical fiber Fabry-Perot pressure sensor is used for detecting the relative pressure and absolute pressure of liquid and gas as well as sound wave signals, ultrasonic wave signals and the like. The structure of the optical fiber Fabry-Perot pressure sensor mainly comprises an optical fiber, an elastic diaphragm, a sensor body and a miniature spring. Two methods and an alternative method can be adopted to form a Fabry-Perot cavity and fabricate the sensor. The elastic diaphragm and the sensing optical fiber are tightly contacted in a plane-sphere point contact manner; when the outside pressure is changed to cause the deformation of the elastic diaphragm, the diaphragm can drive the optical fiber to axially move in the sensor body, so that the length of the Fabry-Perot cavity of the optical fiber is changed; after a broadband light source is connected, by scanning the spectrum of the light passing through the optical fiber Fabry-Perot pressure sensor or extracting low-coherence interference fringes, the change of the cavity length can be extracted, and thereby pressure information can be obtained. The structure can avoid the defect that the diaphragm of the conventional optical fiber Fabry-Perot pressure sensor cannot be over-deformed, and can obtain higher measurement precision.

The encoder / decoder design for spectrum-encoded optical CDMA systems uses waveguide circuits monolithically integrated on one chip to fulfill essential encoding and decoding functions. The integrated device functions as a 1x2 wavelength selective Mach-Zehnder interferometer switch to encode the input broadband light source and to decode the transmitted spectrally encoded signals. The device comprises a frontal 3-dB coupler, a double-ended arrayed-waveguide grating (AWG), and arrays of thermooptic phase shifters and attenuators, together with their symmetric images reflected from the high-reflection coated facet, to realize all required functionality. The thermooptic phase shifters and attenuators are programmable through electronic interface to realize programmable encoding and decoding capabilities. The attenuators are used to equalize the powers and to increase the ON / OFF extinction ratio of all spectral chips.

An optical fiber grating wave length demodulation system belongs to the technical field of optical fiber sensing and optical measurement. The demodulation system comprises a broad band light source (1), a tunable filter (2), a 1x2 coupler, a wave length calibration module, a photodetector, a 1xN optical switch (5) and a signal processing system. The inside connection of the wave length calibration module is that: one end of a standard tool filter (6) is connected with an output end of a third 1x2 coupler (11)m the other end of the standard tool filter is connected with a reference grating (10), an input end of the third 1x2 coupler is connected with an output end of a first 1x2 coupler; the other output end of the third 1x2 coupler is connected with a signal processing system (9) by a second photodetector (4) to implement the wave length calibration. The calibration of the reflected optical fiber grating wave length can be implemented rapidly and accurately by the standard tool filter and the reference grating, the signal can be effectively demodulated for high precision. The system also can be used for monitoring temperature and stress and so on physical quantities.

A fiber optic sensor, which includes an interference energy analyzer, is used to measure strain and temperature distribution along a test fiber. The sensor includes the following: a plurality of double-Bragg grating elements positioned along a test fiber, a broadband light source which produces a broadband spectral profile that propagates along the test fiber, an optical filter that is able to change the parameters of the broadband spectral profile, an optical reflection detector, a fiber optic beamsplitter, and an interference energy analyzer. Each double-Bragg grating element consists of two weak Bragg gratings, separated by a distance unique to each element. The interference energy analyzer calculates the energies of the interference patterns, which are created by beams reflected from double-Bragg grating elements. The energy of the interference signal changes when the gratings in one element non-uniformly change its parameters due to non-equal temperature or strain influence on two gratings.