32results about How to "Low-distortion ," patented technology

The invention provides a wide-angle, low-cost endoscopic objective optical system that is reduced in terms of distortion and field curvature and composed only of spherical lenses, especially a video endoscopic objective optical system. The optical system comprises a first group G1 comprising a negative meniscus lens convex on an object side thereof, an aperture stop S, a second group G2 comprising a positive lens having a plane directed toward an object point side, a third group G3 including at least one concave refractive surface and having a positive refracting power as a whole, and a fourth group G4 comprising a cemented lens comprising a negative meniscus lens and a double-convex lens and having positive refracting power, so that an image is formed at an imaging device I via the first group G1 to the fourth group G4. A chief ray is reflected at the convex surface of the positive lens in the second group in a direction away from an optical axis.

Disclosed is an apparatus for forming a high contrast image of a patterned object, such as a fingerprint, including a first lens having a light receiving surface and a viewing surface and a second lens adjacent to the viewing surface of the first lens. A light source projects incident light into the first lens between the viewing surface and imaging surface such that at least a portion of the incident light undergoes total internal reflection. In this way, an image of the patterned object is generated by substantially all scattered light from the imaging surface.

The present invention allows amplification with low distortion and high efficiency.A power amplifier of the present invention comprises signal conversion means which generates a digital signal and an analog signal from an input signal that is an amplification target based on a signal generation parameter, a switching amplifier which amplifies the digital signal, a linear amplifier which amplifies the analog signal, and DC level detection means which detect a DC level of at least one of the signal amplified by the linear amplifier and the amplified signal and output a detection result to the signal conversion means, wherein the signal conversion means adjust the signal generation parameter so that the DC level inputted by the DC level detection means is virtually equal to zero.

In a variable matching circuit including an impedance device and a variable-capacitance capacitor, the variable-capacitance capacitor is formed in a manner that a plurality of variable-capacitance devices using thin film dielectric layers whose dielectric constants change depending on applied voltages are connected to each other in parallel regarding a direct current and connected to each other in series regarding a high frequency, between an input terminal and an output terminal. The variable matching circuit can be realized that can make the maximum use of the rate of a capacitance change of the variable-capacitance capacitor by a bias signal and make an impedance matching, that exhibits small waveform distortion and intermodulation distortion, and that is excellent in electric high power handling capability and low-loss even at a high frequency.

A five-piece optical imaging lens, in order from an object side to an image side, includes: an aperture stop; a first lens element with a positive refractive power having an object-side surface being convex near an optical axis and the image-side surface being concave near the optical axis; a second lens element with a negative refractive power having an object-side surface being convex near the optical axis and an image-side surface being concave near the optical axis; a third lens element with a negative refractive power having an image-side surface being concave near the optical axis; a fourth lens element with a positive refractive power having an object-side surface being concave near the optical axis and an image-side surface being convex near the optical axis; a fifth lens element with a negative refractive power having an image-side surface being concave near the optical axis.

A wide angle optical lens assembly includes a first lens group and a second lens group arranged in order from an object side to an image plane along an optical axis, satisfying the following condition: 2.0≤|F1 / EFL|≤3.65; 2.6≤|F2 / EFL|≤3.45; wherein, EFL is effective focal length of the wide angle optical lens assembly; F1 is effective focal length of the first lens group; F2 is effective focal length of the second lens group. The first lens group includes a first lens having negative refractive power, a second lens having negative refractive power, and a third lens having positive refractive power arranged in order from the object side. The second lens is a meniscus lens, having a convex image-side surface. The second lens group includes a fourth lens having positive refractive power, a fifth lens having negative refractive power, and a sixth lens having positive refractive power arranged in order from the object side.

The invention discloses automatic corrugated pipe detection equipment, which is used for detecting external defects of corrugated pipes produced by a corrugated pipe production line. The automatic corrugated pipe detection equipment is characterized in that the equipment comprises a pipe inlet hole, a conveying device (1), an image acquisition device (2), a judgment device (3) and a pipe outlet hole; the corrugated pipe coming from the corrugated pipe production line enters the conveying device (1) from the pipe inlet hole of the equipment and is output from the pipe outlet hole after the corrugated pipe is detected; guide rails (11) which are used for bearing the corrugated pipe and elastic pressing wheels (12) used for clamping the corrugated pipe to enable the corrugated pipe to drive are arranged in the conveying device (1); the image acquisition device (2) is provided with two or more than two image sensors (21), and the image sensors (21) are installed in the conveying device (1) and are arranged on the two sides of the guide rails on which the corrugated pipe is conveyed; and the judgment device (3) is connected with the image acquisition device (2), and is used for processing according to corrugated pipe images acquired by the image acquisition device (2) to obtain the actual parameters of the detected corrugated pipe and comparing the actual parameters with parameters in a digital template of a standard corrugated pipe sample to judge whether the corrugated pipe has defects or not.

The invention belongs to the technical field of the signal processing, and relates to a fault extracting method based on improved wavelet packet threshold denoising and local mean value decomposing. The method comprises the following steps: firstly sampling a signal, determining a number of wavelet packet decomposing layers and performing wavelet packet decomposing on the sampled signal, to obtaina decomposed wavelet packet coefficient; and performing quadratic weighting related threshold denoising on the wavelet packet coefficient, reconstructing the denoised wavelet packet coefficient to obtain a denoising signal, and performing LMD decomposing on the denoising signal, to obtain multiple PF components; further calculating a mean square error value, kurtosis and a root-mean-square valueof the PF components, and an energy proportion and a K-L divergence degree of the denoising signal, and according to these index values, to obtain a comprehensive evaluation index, screening out the PF components corresponding to the previous indexes which are as shown in the description; finally, performing envelope demodulation on the PF components, and extracting fault character frequency. Themethod is capable of improving the denoising effect of the sampled signal, highlighting a weak fault character in strong background noise, and effectively improving accuracy of bearing fault diagnosis.

In a variable matching circuit including an impedance device and a variable-capacitance capacitor, the variable-capacitance capacitor is formed in a manner that a plurality of variable-capacitance devices using thin film dielectric layers whose dielectric constants change depending on applied voltages are connected to each other in parallel regarding a direct current and connected to each other in series regarding a high frequency, between an input terminal and an output terminal. The variable matching circuit can be realized that can make the maximum use of the rate of a capacitance change of the variable-capacitance capacitor by a bias signal and make an impedance matching, that exhibits small waveform distortion and intermodulation distortion, and that is excellent in electric high power handling capability and low-loss even at a high frequency.

A base transceiver station for a radio communication system comprises a transmitter unit (TU), a receiver unit (RU) and a transmit path between the transmitter unit (TU) and an antenna. The receiver unit (RU) determines output data from received signals and the transmitter unit (TU) converts input data into transmitted signals and pre-distorts the transmitted signals using at least one compensation value. The base transceiver station comprises also a branching unit for transferring at least a portion of a transmitted signal from the transmit path to the receiver unit (RU) and a processing unit (PU) which is adapted to receive a representation of the input data and the output data. The processing unit (PU) compares the input data to the output data, determines a first compensation value for the pre-distortion according to the comparison and updates the compensation value of the transmitter unit (TU) with the first compensation value. Methods and computer programs embodying the invention are also described.

The invention relates to the field of artificial intelligence speech enhancement, and particularly discloses a speech enhancement model training and application method, device and equipment, and a storage medium, and a speech enhancement model with small distortion and noise reduction capability is obtained through joint modeling of the speech enhancement model and a vocoder. The method comprises the following steps: performing analog noise addition on clean speech to obtain noisy speech, and determining a target time-frequency mask according to the clean voice and the noisy speech; extracting noisy Mel spectrum features from the noisy speech, inputting the noisy Mel spectrum features into the speech enhancement model, outputting a predicted time-frequency mask, and determining a first loss value according to the predicted time-frequency mask and a target time-frequency mask; obtaining de-noised Mel spectrum features according to the predicted time-frequency mask and the noisy Mel spectrum features; and inputting the de-noised Mel spectrum features into a vocoder to obtain synthetic speech, and determining a second loss value according to the synthetic speech and the clean speech. And optimizing parameters of the speech enhancement model and the vocoder according to the first loss value and the second loss value to obtain a trained speech enhancement model.

A signal generation section 11 generates an amplitude signal M and an angle-modulated signal Sθ. An adaptive compensation filter 12 performs waveform shaping on the amplitude signal M in accordance with a magnitude of the amplitude signal M. An amplitude amplification section 14 outputs a signal proportional to a magnitude of the signal subjected to waveform shaping in the adaptive compensation filter 12. An amplitude modulation section 15 amplitude-modulates the angle-modulated signal by the signal outputted from the amplitude amplification section 14 and outputs the resulting signal as a modulated signal. Characteristics of the adaptive compensation filter 12 are inverse characteristics of transfer characteristics from an input of the amplitude amplification section 14 to an output of the amplitude modulation section 15.

The invention relates to a beam structure vibration fatigue device. The device comprises a beam test piece, a beam end clamping seat, a vibration platform, a vibration motor, a vibration isolation spring and a base, one end of the beam test piece is installed on the beam end clamping seat or the two ends of the beam test piece are installed on the beam end clamping seat, the beam end clamping seatis installed on the vibration platform, and the vibration motor is installed on the vibration platform. An eccentric block is mounted at the output shaft of the vibration motor, a vibration isolationspring supports the vibration platform, one end of the vibration isolation spring is connected to the base, and the other end of the vibration isolation spring is connected with the vibration platform. Under the action of exciting force, the vibration platform and accessories installed on the vibration platform can generate forced vibration, and the beam test piece and the beam end clamping seatvibrate along with the vibration platform. Because the end part of the beam test piece is fixed, the vibration deformation part is not connected with the vibration platform, the vibration deformationof the beam test piece does not influence the vibration of the vibration platform, and the distortion degree of the generated vibration waveform is small. In addition, the fatigue test of a cantileverbeam, a simply supported beam and the fixed beams at the two ends can be realized through one device.

The invention provides an F-theta lens for laser processing. The F-theta lens comprises a first lens with positive focal power, a second lens with negative focal power, a third lens with positive focal power, a fourth lens with positive focal power and a fifth lens with positive focal power. The F-theta lens is enabled to have the characteristics of large field of view, low telecentricity and small distortion through optimizing the mirror surface curvature of the lenses, the measurement error of light spots in the horizontal direction during laser processing is effectively reduced, and the distortion of laser spots within the scanning field of view range is well suppressed.

The invention discloses an intelligent pillow based on remote real-time sleep quality monitoring. The intelligent pillow comprises a pillow body; an inner cavity is formed in the pillow body; a left air bag bin and a right air bag bin for mounting a left air bag and a right air bag respectively are arranged in the inner cavity; a neck supporting groove is formed between the left air bag bin and the right air bag bin; a protective cushion layer is arranged in the neck supporting groove; a control box is mounted on the front side of the pillow body; a controller and a micro air pump are mountedin the control box; the micro air pump is connected with the left air bag and the right air bag through air pipes; a plurality of sensors are embedded in the surface of the pillow body; and the plurality of sensors are connected with the controller. The intelligent pillow is novel in structural design and convenient to use, can monitor the sleep quality of a user in real time, and can immediatelysend out an alarm signal when monitoring abnormity.

The invention discloses a light and small coaxial-like five-reflex optical system with a large field of view and low distortion, and relates to the field of aerospace optical remote sensors. The lightand small coaxial-like five-reflex optical system with a large field of view and low distortion comprises an aperture diaphragm, a primary mirror, a secondary mirror, a third mirror, a fourth mirror,a fifth mirror and a plane mirror; the light passes through the primary mirror, the secondary mirror, the plane mirror, the third mirror, the fourth mirror, the fifth mirror in turn to form an imageon an image surface; the aperture diaphragm is located on the primary mirror; the primary mirror is inclined with respect to an optical axis of the light incident on the primary mirror; the plane mirror, the third mirror, the fourth mirror, and the fifth mirror are all located behind the primary mirror; the primary mirror is a quadric surface; the secondary mirror, the third mirror, the fourth mirror and the fifth mirror are all high-order spherical surfaces; and the primary mirror and the secondary mirror constitute a concave reflector group. The invention has the characteristics of small size, low cost, low distortion, large field of view, wide spectral range, no obstruction, long focal length, etc., and can realize high-precision ground detection and mapping, is especially used as a high resolution camera with a small size and low cost of a micro-nano satellite.

The invention discloses an image defogging method and device based on image sky segmentation, and a storage medium, and belongs to the technical field of image defogging, and the method comprises thefollowing steps: carrying out the hybrid image preprocessing of an original image containing a sky region, and obtaining a new image, wherein the hybrid image preprocessing comprises gradient sharpening, mean filtering smoothing, secondary sharpening, masking and addition processing in sequence; carrying out image segmentation processing on the new image by adopting an Ostu threshold segmentationalgorithm to obtain a sky region image and a non-sky region image, and respectively carrying out defogging processing on the sky region image and the non-sky region image to obtain a non-sky region defogged image and a sky region defogged image; and fusing the sky area defogged image and the non-sky area defogged image by using the binary mask of the sky area and the binary mask of the non-sky area to obtain a final defogged image. Image details can be effectively kept, the image contrast is improved, and sky area color distortion is eliminated.

The invention discloses a method and a system for determining malicious codes based on calling relations. The method comprises: decompiling a to-be-detected program and obtaining pseudocode; analyzingthe pseudocode and establishing a calling structure tree; traversing the calling structure tree, to obtaining behavior data of the to-be-detected program, when the obtained behavior data is matched with predefined malicious behavior data, determining that the to-be-detected program has malicious codes, wherein the malicious behavior data includes malicious behavior, and calling relations or calling positions of malicious behaviors. In the technical scheme, through converting the calling relations of programs to hierarchical relations of the calling structure tree, more detailed program information is provided to a machine, and finally accuracy of malicious code determination is improved.

A power circuit of an AC power supply comprises a power input unit connected to a AC / DC converter. The AC / DC converter is connected to a DC / DC circuit, and the DC / DC circuit is further connected to an adjustable DC voltage regulation circuit. The adjustable DC voltage regulation circuit is connected to an amplifier to amplify and convert the DC voltages into the AC voltages, thereby outputting different AC voltages and electric currents under the condition of not switching off the output when adjusting the voltage via cross position, so that a power level is switched promptly and a very low power distortion.

A first magnet is provided in an upper case and a second magnet is provided in a lower case so that these magnets face each other. These magnets are magnetized in opposite directions. A diaphragm having a drive coil is placed between these magnets. Thus, magnetic flux emitted from the respective magnets bends in a direction approximately perpendicular to the initial direction of emission of the flux. In the magnetic field, the component of the magnetic flux in the direction of radiation proportional to the driving force is dominant, and is symmetrical relative to the direction of vibration. Therefore, the sound pressure of the reproduced sound is increased and the secondary harmonic distortion caused by asymmetry of the driving force can be reduced.

The invention provides a three-dimensional stereo playback system based on a panoramic circular shooting technology. The method comprises the steps that a user starts a circular shooting device to carry out 360-degree circular shooting on a scene to be recorded; an image collection device transmits the shot multi-angle images to a processor; the processor carries out data processing and analysis operation on the images and establishes a virtual space coordinate system for carrying out stereo recombination on the shot images, three-dimensional data is formed and introduced into a memory for storage; and after the user selects a scene playback function, the system introduces related data into a three-dimensional stereo image screen, the three-dimensional stereo images are displayed by the screen, and the three-dimensional stereo playback based on the panoramic circular shooting technology is finally completed. The system is low in distortion degree and displays the three-dimensional stereo images which are real and sensible in height, width and thickness, so that more visual images are provided for penalties of judges on a match field, the accuracy and reliability of the penalties are improved, and the enjoyment of a football match is increased.

The invention relates to a digital interphone signal demodulation device, relates to the field of signal demodulation and solves problems that demodulation signals are poor in stability and high in distortion degree due to device ageing and temperature changes. The digital interphone signal demodulation device comprises a voltage-controlled oscillator, a mixer, a frequency discriminator and a voltage output module, and the voltage-controlled oscillator produces local oscillation signals according to control levels output by the voltage output module; the mixer mixes the local oscillation signals with radio-frequency signals received by antennas to obtain intermediate frequency signals; the frequency discriminator performs frequency discrimination and demodulation to the intermediate frequency signals and outputs the demodulation signals; and the voltage output module outputs the control levels according to the demodulation signals, calculates direct current components in the demodulation signals and compares calculating results with reference direct current components, and if deviation is larger than a direct current threshold value, the control levels output to the voltage-controlled oscillator are changed till the deviation is smaller than the direct current threshold value. The digital interphone signal demodulation device is used for improving stability of the demodulation signals and reducing the distortion degree of the demodulation signals.

The invention relates to a wireless and wired compatible earphone system . The earphone system comprises a micro-control unit, a memory module, an audio decoding power amplifier module, a sound production module and a switch element, and the output end of the switch element is connected with a wireless communication module or an I / O (Input / Output) interface so as to switch the connection between the micro-control unit and the wireless communication module or the connection between the micro-control unit and the I / O interface. Coexistence of a wired system and a wireless system of the earphoneis realized through the switch element, thereby facilitating use of a user. According to the earphone system, the audio decoding power amplifier module and the memory module are adopted, so that the earphone has a function of locally playing an audio file, the distortion degree of the audio file played by the earphone is small by processing an audio signal through the audio decoding power amplifier module, and the tone quality played by the sound production module is better; as the audio decoding power amplifier is compatible with mainstream lossless files with high code rate in the mode, theaudio decoding power amplifier has a low distortion effect on audio transmission of a wired system, the sound quality loss of sound emitted by the sound production module of the earphone is small, andthe sound quality is good.

The invention discloses an indoor article searching and positioning method for visually impaired people. The method comprises the following steps: S1, enabling the visually impaired people to input the name of a target article through a voice module and then collect images indoors through a binocular camera; s2, designing an adaptive sigmoid transfer algorithm (ASTF) based on a neural network, andcombining the ASTF with a Laplace operator to enhance the brightness of the acquired image and reduce the distortion degree; s3, designing a variable-scale convolutional neural network to convolve the images obtained in the step S2 to the same size; s4, designing a convolutional neural network fused with a multi-level attention mechanism to extract feature information of the image obtained in S3,and matching the feature information with feature data of a target object in a database; s5, if matching succeeds, obtaining the position of the target object, and outputing position information of the target object through a voice module; and if the matching is not successful, outputting the information that no information exists through the voice module. According to the invention, visually impaired people can be effectively helped to accurately search articles in a weak light environment.

A method for controlling cross-screen image mosaic distortion, a device and electronic equipment are provided. The method for controlling cross-screen image mosaic distortion is applied in a spliced display screen. The spliced display screen comprises a plurality of sub-display screens spliced in a rectangular array, each sub-display screen has a display area and a border around the display area.The method comprises the following steps: obtaining the number M of sub-display screens of each row and the number N of sub-display screens of each column; acquiring first size information of a display area of the sub-display screen and second size information of a border; setting a virtual display screen corresponding to a display screen according to M, N, the first size information and the second size information, the virtual display screen having a first area corresponding to a display area of each sub-display screen and a second area corresponding to a border; controlling each of the sub-display screens to display a picture of a corresponding area on the first area. The invention has the beneficial effect of reducing picture distortion.

An optical imaging lens, in order from an object side to an image side along an optical axis, includes a first lens having negative refractive power; a second lens; a third lens cemented with the second lens to form a first compound lens having negative refractive power; a fourth lens having positive refractive power; a fifth lens; a sixth lens cemented with the fifth lens to form a second compound lens having positive refractive power; a seventh lens having positive refractive power. The optical imaging lens could provide a better optical performance of high image quality and low distortion.

The invention discloses a method for improving image quality of colorful plasma display screen which comprises: measuring display screen brightness and recording the error between real gray grade and theoretical gray grade in an error look-up device; inputting interface original data to an accumulator, adding the error outputted from look-up device and sending data to a round-off device; getting integer part of data and sending it to a controller and the look-up device for data processing in the controller and being as corresponding error in address look-up table; sending the error to the accumulator for being calculated with next field data; getting the decimal error part after rounded and sending the error to the accumulator for being added with the error data of next field data and look-up device; when accumulating eight fields error data, resetting all error data and performing next cycle field error accumulation.

A power amplifier circuit includes a first amplifier including two amplifiers connected in series with a matching circuit interposed therebetween, a first power supply circuit that supplies a first power supply voltage to a former amplifier of the first amplifier, and a second power supply circuit that supplies a second power supply voltage to a latter amplifier of the first amplifier.

The application discloses a carrier signal processing method and device and a storage medium. The carrier signal processing method comprises the following steps: acquiring a carrier signal to be processed, wherein the carrier signal includes multiple wavelet signals; determining the first number of wavelet signals corresponding to each preset frequency band in a plurality of preset frequency bands; determining a demodulation frequency from the preset frequency band with the largest first number; and performing a demodulation operation on the carrier signal by the demodulation frequency in order to locate the carrier frequency accurately. Thus, the digital signal wave is better restored, and the distortion is low. The method is simple.

The invention relates to a high-voltage power supply device. The high-voltage power supply device comprises a driving unit, a piezoelectric transformer and a smoothing unit. The output of the drivingunit drives the piezoelectric transformer. The smoothing unit comprises a high-voltage diode, a resistor and a first capacitor. The positive pole of the high-voltage diode is connected with the outputend of the piezoelectric transformer, and the negative pole of the high-voltage diode is connected with the first resistor and the first capacitor. The first capacitor is grounded, and the other endof the first resistor serves as the output end. According to the high-voltage power supply device, signals which drive the frequency oscillation are generated by the driving unit, the piezoelectric transformer outputs the maximum voltage at the resonant frequency under the action of the driving signals, the first resistor suppresses the voltage, which is generated by the piezoelectric transformer, of the spurious frequency to generate the voltage at the frequency lower than the resonant frequency, and therefore the degree of distortion of the output voltage is reduced, the output voltage is slightly affected by the external load of the first resistor, temperature changes and other factors, the stable output voltage control is achieved, and the image transfer printing quality is improved.