31 results about "Dual band bandpass filter" patented technology

An image-sensing apparatus is provided. The image-sensing apparatus includes: an optical filter array including a two-band passing filter and an infrared filter; an RGB pixel array placed below the two-band passing filter; and a TOF pixel array adjacent to the RGB pixel array and placed below the two-band passing filter and the infrared filter, wherein a combination of the two-band passing filter and the infrared passing filter permits only the incident light in the infrared region to pass to the ToF pixel array.

A fluorescence detection optical system detects fluorescence beams with two or more different wavelengths and maintains a focal position through an automatic focusing function. A multi-channel fluorescence detection apparatus includes the fluorescence detection optical system. The fluorescence detection optical system includes an automatic focusing unit which receives light reflected off a microfluidic device and determines a focal point by using an astigmatic method or a knife edge method, and an actuator which adjusts a position of an objective lens according to control of the automatic focusing unit. In addition, the fluorescence detection optical system may include a plurality of dual band pass filters, dichroic devices, etc., which provide light beams emitted from at least two light sources and transfer fluorescence generated from the microfluidic device to a photodetector.

A slot-line dual-band bandpass filter comprises a microwave medium dielectric slab substrate, upper microstrip transmission lines and lower slot-line resonators. A third spiral slot-line stub and a first spiral slot-line stub are loaded to a first open ring slot-line resonator to form an open ring slot-line resonator with the loaded spiral slot-line stub. A fourth spiral slot-line stub and a third spiral slot-line stub are loaded to a second open ring slot-line resonator to form an open ring slot-line resonator with the loaded spiral slot-line stub. The two open ring slot-line resonators with the loaded spiral slot-line stub are coupled to input and output feeders by means of clearance coupling and vertical coupling. The slot-line dual-band bandpass filter allows for independent control of central frequency of two bands and circuit miniaturization; power carrying capacity of the microwave filter is improved; microwave filter bandwidth control is realized; stop-band characteristic of the filter is improved effectively; the slot-line dual-band bandpass filter is compact in design and easy to integrate.

An eye tracking apparatus is operable in both first and second illumination environments where the second illumination is associated with a higher illumination environment than the first illumination. The apparatus includes an image capturer configured to capture an image of a user, an image processor configured to detect an eyepoint of the user in the captured image, and an optical source configured to emit infrared light to the user in a first illumination mode. The image capturer includes a dual bandpass filter configured to allow infrared light and visible light to pass.

A device for optical detection of a target gas in gas mixtures includes an operation and evaluation unit, a measurement cuvette with optically reflective surfaces on its interior walls and a gas inlet to the environment, a radiation source, a measuring detector and a reference detector unit provided on the measurement cuvette. The measuring detector and the reference detector unit detect the light of the radiation source and produce electrical signals corresponding to the intensity of the detected light. An optical bandpass filter element, constructed to transmit light of a measurement wavelength, is arranged upstream of the measuring detector. An optical double-bandpass filter unit, that transmits light of a first reference wavelength and light of a second reference wavelength, is arranged upstream of the reference detector unit. The operation and evaluation unit operates the radiation source and acquires the electrical signals of the measurement detector and the reference detector unit.

A dual-band bandpass filter with stepped-impedance resonators uses only one circuit to generate dual-band effect. It adopts the principle of stepped-impedance resonator, which contains a connecting section and two coupling sections. The impedance and electrical length of the connecting section and coupling sections conforms to a selected condition to generate two passbands at desired frequencies. A multi-layer broadside-coupled parallel lines structure may be applied to increase coupling-amount between the parallel lines so that the dual-band bandpass filters have broader bandwidth and less loss.

Two second-order bandpass filter are connected serially to obtain a dual bandpass filter. One is inductive and the other is capacitive. One has a low passband and the other has a high passband. Between them, a finite transmission zero is formed to suppress noise. The present invention achieves a passband as wide as 1 gigahertz so that it can be applied to a wireless local network, communication equipments and electronic devices.

The invention discloses a dual-band bandpass filter based on a single rectangular SIW structure. The present invention is based on a rectangular SIW structure and controls the first four resonant modes of the filter, namely TE101, TE201, TE301 and TE401 modes, by using a method of metal via disturbance. TE101 and TE201 combine to form a first passband, TE301 and TE401 combine to form a second passband. In addition, the bandwidth and spacing of the two passbands can be tuned relatively independently by disturbing vias through movement. At the same time, the offset input and output feeders introduce four transmission zeros into the filter, which improves the stopband attenuation of the filter. By utilizing single SIW cavity mode reasonably, it meets the miniaturization requirement of modernmulti-standard RF system and solves the problems of large size and complex design of a traditional dual-band filter.

A dual-band bandpass filter with stepped-impedance resonators uses only one circuit to generate dual-band effect. It adopts the principle of stepped-impedance resonator, which contains a connecting section and two coupling sections. The impedance and electrical length of the connecting section and coupling sections conforms to a selected condition to generate two passbands at desired frequencies. A multi-layer broadside-coupled parallel lines structure may be applied to increase coupling-amount between the parallel lines so that the dual-band bandpass filters have broader bandwidth and less loss.

The invention relates to a bent dual-band bandpass filter applying a defected ground level waveguide technology, which comprises an upper surface micro-band part and a defected ground level waveguide structure of a ground part, wherein the upper surface micro-band part comprises a micro-band input port (1), a micro-band output port (2) and a pair of T-shaped coupling arms (3) and (4), wherein the input port (1) is coupled to the defected ground level waveguide structure of the ground through the coupling arm (3), and the output port (2) is coupled to the defected ground level waveguide structure of the ground through the coupling arm (4); and the defected ground level waveguide structure of the ground part is formed by bending and winding a big square defected ground level waveguide ring into three square defected ground level waveguide rings, wherein the three square defected ground level waveguide rings are respectively a defected ground waveguide square ring (5) which is positioned at the outermost layer, a defected ground waveguide square ring (6) which is bent inward and is positioned at the middle layer, and a defected ground waveguide square ring (7) which is bent inward and is positioned at the innermost layer. The invention is applied in intensive integrated circuits.

A fluid identification assembly is provided to determine the presence or absence of multiple components within a fluid in a conduit. The assembly includes a light source and a light detector positioned to receive a portion of light from the light source reflected by the conduit and fluid. A dual-band bandpass filter may be associated with the light detector to allow multiple wavelengths of light to be monitored, thereby monitoring the composition of the fluid based on the amount of light of each wavelength absorbed by the fluid. Rather than a dual-band bandpass filter, a second light detector may be provided, along with a beam splitter to separate light from a single source for receipt of light of different wavelengths by the light detectors. The dual-band bandpass filter may also be replaced by a second light source and detector pair for analyzing fluid using multiple wavelengths of light.

The invention discloses a double-frequency phase locking method based on a dual-band-pass filter. The double-frequency phase locking method is applied to extraction of positive and negative sequence component amplitudes, phase positions and frequencies under unbalanced states of network voltages. According to the method, two new transformational matrixes T+' and T-' are established to extract double-frequency fluctuation Vd+' and Vq+' both generated by a network voltage positive sequence component and double-frequency fluctuation Vd-' and Vq-' both generated by a network voltage negative sequence component, the dual-band-pass filter is used for extracting a double-frequency component, and the phase positions of the network voltage positive sequence component and the network voltage negative sequence component are locked accurately when the double-frequency component is locked accurately. By the double-frequency phase locking method, detection speed and accuracy of the positive and negative sequence component amplitudes, the phase positions and the frequencies can be improved; in terms of new energy grid connection and situations in need of quick extraction of the positive sequence component and the negative sequence component, the double-frequency phase locking method has a certain engineering application value.

The invention relates to an HMCSIW double-band-pass filter loaded with L-shaped branch lines, which takes an HMCSIW as a basic transmission line and comprises a dielectric substrate, a top metal layer arranged on the upper surface of the dielectric substrate and a bottom metal layer arranged on the lower surface of the dielectric substrate, and a plurality of U-shaped slots are etched on the top metal layer of the dielectric substrate, so that a broadband mother filter is realized; two L-shaped branch lines are loaded on the wide side of the top metal layer, the distance between the two L-shaped branch lines is used for generating a transmission zero point, two sets of gradually-changed rectangular grooves are etched in the bottom metal layer of the dielectric substrate and are divided into transition areas located at an input port and an output port, and the stop-band bandwidth is widened. Three U gaps are introduced into the upper surface of the HMCSIW to realize a broadband mother filter, a source and a load are coupled through two L-shaped branch lines, a transmission zero point is generated, a mother passband is split into two sub passbands, and finally the dual-passband filter is constructed.

The present invention relates to a dual-band bandpass resonator and a dual-band bandpass filter. The dual-band bandpass filter according to the present invention includes a plurality of dual-band bandpass resonators. The dual-band bandpass resonator includes a central conductor having a central axis aligned with an input / output direction, a pair of grounding conductors, a central conductor short-circuit part and a pair of stub conductors that are formed on a surface of a dielectric substrate. The pair of grounding conductors are disposed on the opposite sides of the central conductor with a space interposed therebetween. The central conductor short-circuit part short-circuits the pair of grounding conductors, and one end of the central conductor is connected to the central conductor short-circuit part. The pair of stub conductors are disposed in the spaces on the opposite sides of the central conductor symmetrically with respect to the central axis of the central conductor, extend at least partially parallel with the central conductor and are connected to the central conductor short-circuit part at one ends thereof.

A fluorescence detection optical system detects fluorescence beams with two or more different wavelengths and maintains a focal position through an automatic focusing function. A multi-channel fluorescence detection apparatus includes the fluorescence detection optical system. The fluorescence detection optical system includes an automatic focusing unit which receives light reflected off a microfluidic device and determines a focal point by using an astigmatic method or a knife edge method, and an actuator which adjusts a position of an objective lens according to control of the automatic focusing unit. In addition, the fluorescence detection optical system may include a plurality of dual band pass filters, dichroic devices, etc., which provide light beams emitted from at least two light sources and transfer fluorescence generated from the microfluidic device to a photodetector.

Two second-order bandpass filter are connected serially to obtain a dual bandpass filter. One is inductive and the other is capacitive. One has a low passband and the other has a high passband. Between them, a finite transmission zero is formed to suppress noise. The present invention achieves a passband as wide as 1 gigahertz so that it can be applied to a wireless local network, communication equipments and electronic devices.

The invention discloses a compact type UWB dual-band trap balancing band-pass filter, and belongs to the technical field of wireless communications. The compact type UWB dual-band trap balancing band-pass filter comprises a first filter, a second filter and supplement structures. The first filter and the second filter are in structural symmetry and respectively comprise a microstrip line structure formed on the upper layer of a dielectric substrate and a trough line structure formed on the lower layer of the dielectric substrate. In order to restrain common-mode harmonic waves and achieve dual-band trap characteristics, the supplement structures are additionally arranged in the microstrip line structures on the upper layers of the dielectric substrates, each supplement structure comprises a first microstrip branch knot, a second microstrip branch knot, a first harmonic oscillator, a second harmonic oscillator, a third harmonic oscillator and a fourth harmonic oscillator, wherein the first harmonic oscillator and the second harmonic oscillator are arranged on the two sides of the first microstrip branch knot in parallel, and the third harmonic oscillator and the fourth harmonic oscillator are arranged on the two sides of the second microstrip branch knot in parallel. The compact type UWB dual-band trap balancing band-pass filter has a wide different-mode signal passband and has the dual-band trap characteristics, a high common-mode restraining characteristic is achieved in the passband, the structure is compact, circuits are simple, and processing is easy.

The invention provides a GSM-R base station with high suppression of interference signals, including a base transceiver station BTS and its antenna, a pair of double band-pass filters or a pair of double band-pass filters are installed between the base transceiver station BTS and the antenna GSM-R coupler, described double-bandpass filter or double-bandpass GSM-R coupler comprises high-frequency signal insertion port RFin and radio-frequency signal port RFout, and high-frequency signal insertion port RFin is N-K radio frequency head, connects The 1 / 2 feeder is connected to the GSM‑R base station, and the RF signal port RFout is the L29 (7 / 8)‑K radio head, which is connected to the 7 / 8 feeder and connected to the antenna. The present invention compresses the receiving bandwidth of the GSM-R base station through the double-band-pass filter or the double-band-pass GSM-R coupler, reduces the floor noise level, suppresses the out-of-band large signal interference, and prevents the transceiver of the GSM-R base station Blocking, and effectively reduces intermodulation interference to GSM‑R base station transceivers.

A glazing unit with a glass panel that is low in reflectance for RF radiation, a coating system that is high in reflectance for RF radiation disposed on the glass panel and creating onto the glazing unit a dual band bandpass filter. The glazing unit further features at least one frequencies selective decoated portion of the coating system extending along a plane, P, defined by a longitudinal axis, X, and a vertical axis, Z; having a width, DW, measured along the longitudinal axis, X, and a length, DL, measured along the vertical axis, Z. The frequencies selective decoated portion includes a first decoated element with a plurality of unit cells forming a regular grid, and a plurality of second decoated elements wherein a second decoated element is placed in each unit cell of the first decoated element and no second decoated element is in contact with the first decoated element.

To provide a tunable dual-band resonator capable of independently tuning the center frequency, and a tunable dual-band band-pass filter using the resonator. A dual-band resonator is structured such that a stub 11 is added to each half-wavelength resonator 10 provided with half-wavelength resonator protrusions (capacity-component adjust parts) 10-a, 10-b. A tunable dual-band resonator capable of tuning resonance frequencies in an even-number mode and an odd-number mode independently is configured by providing a dielectric rod circular in cross section in the space above the half-wavelength resonator protrusions (capacity-component adjust parts) 10-a, 10-b. Each half-wavelength resonator 10 is formed of one thin strip conductor with a deeply retreated groove having a width g. A tunable dual-band band-pass filter is configured by arranging a plurality of the tunable dual-band resonators.

The present invention discloses an improved a glazing unit comprising a glass panel which is low in reflectance for RF radiation, a coating system which is high in reflectance for RF radiation disposed on the said glass panel and creating onto the glazing unit a dual band bandpass filter. The glazing unit further comprises at least one frequencies selective decoated portion of the coating system extending along a plane, P, defined by a longitudinal axis, X, and a vertical axis, Z; having a width, DW, measured along the longitudinal axis, X, and a length, DL, measured along the vertical axis, Z. The at least one frequencies selective decoated portion comprises a first decoated element comprising a plurality of unit cells forming a regular grid. The at least one frequencies selective decoated portion further comprises a plurality of second decoated elements wherein a second decoated element is placed in each unit cell of the first decoated element and wherein no second decoated element is in contact with the first decoated element.

The present invention provides a dual-band bandpass filter with high selectivity, comprising two first microstrip lines, an input end, an output end, and a second microstrip line provided on the upper surface of a dielectric slab. Both ends of each first microstrip line are provided with an open load and a shorted load, respectively; the middle parts of the two first microstrip lines are connected by means of the second microstrip line; the input end is connected to one of the first microstrip lines, and the output end is connected to the other first microstrip line; both ends of the second microstrip line are respectively communicated with the input end and the output end, and are located on the same horizontal line; the horizontal line serves as a first central axis; a second central axis is perpendicular to the first central axis; the tail end of the shorted load is provided with a shorted metal post, which is connected to a ground metal layer provided on the lower surface of the dielectric slab. The dual-band bandpass filter with high selectivity of the present invention exerts a good suppression effect on out-of-band signals, has high selectivity, introduces less noise, and avoids interference to a radio frequency front end.

The invention discloses a reconfigurable dual-band band-pass filter which comprises an upper microstrip line structure, a middle dielectric substrate, a lower grounding metal patch and a metal through hole, wherein the metal through hole penetrates through the microstrip line structure, the dielectric substrate and the grounding metal patch in sequence to enable the microstrip line structure to be connected with the grounding metal patch through the dielectric substrate; the microstrip line structure comprises a first resonator, a second resonator, a third resonator and a fourth resonator; the first resonator and the second resonator are coupled to form a group of resonators after being folded; the third resonator and the fourth resonator are coupled to form another group of resonators after being folded; through the two groups of resonators, the microstrip line structure integrally forms a grid-shaped structure; one end of each resonator is loaded with a variable capacitance diode. According to the reconfigurable dual-band band-pass filter provided by the invention, the integration level and the electromagnetic compatibility of the system are improved; two pass bands are independently reconfigurable and the absolute bandwidth is basically constant, so that the application requirement of the conventional dual-band wireless communication system can be better satisfied.

The invention provides a photonic crystal double-band-pass filter which comprises a first metal plate, a second metal plate, metal columns and defect metal columns, the first metal plate and the second metal plate are correspondingly arranged, and the metal columns are arranged between the first metal plate and the second metal plate in a two-dimensional periodic mode. Two opposite ends of the metal columns are respectively contacted with the first metal plate and the second metal plate to form a metal column array; the height of the defective metal columns is smaller than that of the surrounding metal columns, the defective metal columns comprise first defective metal columns and second defective metal columns which have different cross sectional areas so as to form defective sub-periodic structures, and the defective sub-periodic structures are arranged in the metal column array in a two-dimensional periodic mode. The invention provides a photonic crystal double-band-pass filter which can be used for 6G communication and optical communication in the future, and fills the blank in the field.

A spectrum-inspection device includes: a sensor unit array including a first sensor unit and a second sensor unit; a dual-band pass filter disposed on the sensor unit array to cover the first sensor unit and the second sensor unit, wherein the dual-band pass filter allows a first waveband and a second waveband of a light beam to pass through; and a filter disposed on the dual-band pass filter to cover the second sensor unit, wherein the filter allows wavelengths of a light beam longer than a first wavelength to pass through, wherein the first wavelength is longer than a peak wavelength of the first waveband and shorter than a peak wavelength of the second waveband.

A device for optical detection of a target gas in gas mixtures includes an operation and evaluation unit, a measurement cuvette with optically reflective surfaces on its interior walls and a gas inlet to the environment, a radiation source, a measuring detector and a reference detector unit provided on the measurement cuvette. The measuring detector and the reference detector unit detect the light of the radiation source and produce electrical signals corresponding to the intensity of the detected light. An optical bandpass filter element, constructed to transmit light of a measurement wavelength, is arranged upstream of the measuring detector. An optical double-bandpass filter unit, that transmits light of a first reference wavelength and light of a second reference wavelength, is arranged upstream of the reference detector unit. The operation and evaluation unit operates the radiation source and acquires the electrical signals of the measurement detector and the reference detector unit.

The invention relates to a bent dual-band bandpass filter applying a defected ground level waveguide technology, which comprises an upper surface micro-band part and a defected ground level waveguide structure of a ground part, wherein the upper surface micro-band part comprises a micro-band input port (1), a micro-band output port (2) and a pair of T-shaped coupling arms (3) and (4), wherein the input port (1) is coupled to the defected ground level waveguide structure of the ground through the coupling arm (3), and the output port (2) is coupled to the defected ground level waveguide structure of the ground through the coupling arm (4); and the defected ground level waveguide structure of the ground part is formed by bending and winding a big square defected ground level waveguide ring into three square defected ground level waveguide rings, wherein the three square defected ground level waveguide rings are respectively a defected ground waveguide square ring (5) which is positioned at the outermost layer, a defected ground waveguide square ring (6) which is bent inward and is positioned at the middle layer, and a defected ground waveguide square ring (7) which is bent inward and is positioned at the innermost layer. The invention is applied in intensive integrated circuits.