696results about How to "Small distortion" patented technology

The invention relates to the technical field of optical detection, in particular to a workpiece surface defect detection method and system based on the optical technology, and the method comprises the following steps: S1, generating a curvature model of a workpiece; s2, dynamically adjusting the irradiation angle and the light spot shape of a light source according to the curvature model in the S1; s3, adjusting the focal length of the detection equipment in real time; s4, imaging acquisition is carried out on the workpiece at the same time through multiple angles; s5, correcting image distortion caused by surface curvature change, and fusing the multi-angle images into a high-precision workpiece surface image; s6, defect features of the surface of the workpiece are extracted, defects are classified, positions are marked, and a defect detection report is generated; according to the invention, by dynamically adjusting the light source and the focal length and combining multi-view imaging and advanced image processing technologies, efficient and accurate defect detection is realized, and the product quality and the production efficiency are remarkably improved.

The embodiment of the invention discloses a midpoint potential control method based on a diode clamping type three-level grid-connected inverter and a related device. The method comprises the following steps: generating an initial three-phase modulation wave through a current loop closed-loop control method according to a collected three-phase current value and a three-phase voltage value of a power grid side of the diode-clamped three-level grid-connected inverter; according to an initial modulation waveform generated by the initial three-phase modulation wave, a three-phase current value and an acquired voltage value of a voltage dividing capacitor at the direct current side of the diode clamping type three-level grid-connected inverter, calculating a zero-sequence component required by neutral-point potential balance; superposing a zero-sequence component required by neutral-point potential balance with the initial modulation waveform to obtain a final modulation wave; and generating a driving signal matched with each phase of bridge arm in the diode clamping type three-level grid-connected inverter according to the final modulation wave. By adopting the invention, the neutral-point voltage can be balanced, the distortion of the output waveform at the alternating current side is reduced, the voltage stress of the device is reduced, and the service life of the power device is prolonged.

The invention relates to the technical field of audio processing, in particular to an intelligent power amplifier calibration method, system and device. The method comprises the following steps: monitoring corresponding voltage and current waveforms of a power amplifier in real time and carrying out load impedance response analysis to obtain power amplifier load impedance; acquiring a power amplifier output audio signal, and performing spectrum analysis and audio distortion detection to obtain a power amplifier output audio distortion degree; performing gain self-adaptive adjustment on the power amplifier based on the power amplifier output audio distortion degree to obtain power amplifier output self-adaptive adjustment gain; performing frequency response optimization corresponding to different frequency bands on the power amplifier output audio frequency spectrum to generate power amplifier response optimization output frequencies corresponding to different frequency bands; and performing intelligent feedback calibration on the power amplifier based on the power amplifier output adaptive adjustment gain and the power amplifier response optimization output frequency corresponding to different frequency bands to generate an intelligent calibration power amplifier. The overall performance and the use experience of the power amplifier can be improved.

The invention discloses a sensitivity compensation method and system based on a TMR sensor. The method comprises the steps that a temperature compensation circuit introduces a negative temperature coefficient temperature sensitive resistor to be connected with a TMR current sensor in series; a fitting compensation technology is used, the corresponding relation between the temperature and the sensitivity of the sensor is accurately measured, data fitting is carried out through a least square algorithm, and a mapping curve of the temperature and the sensitivity is obtained; constructing and training a neural network model for learning and simulating a complex mapping relationship between environmental factors of a space geomagnetic field and temperature and measurement output of the TMR current sensor; and performing real-time correction compensation on the original output signal of the TMR current sensor by using the trained neural network model according to the environment temperature information acquired by the upper computer in real time and the correction factor predicted by the model. Through a unique compensation mechanism and an optimization algorithm, the accuracy of current signal acquisition and the stability of the system are remarkably improved, and the influence of environmental factors is reduced.

The invention provides an optical lens and electronic equipment with the same, and the optical lens comprises a first lens which has negative focal power, the first side surface of the first lens is a convex surface, and the second side surface of the first lens is a concave surface; the second lens has negative focal power, the first side surface of the second lens is a concave surface, and the second side surface of the second lens is a convex surface; the third lens has positive focal power; the fourth lens has positive focal power; the fifth lens has positive focal power, and the first side surface and the second side surface of the fifth lens are convex surfaces; a sixth lens, wherein the sixth lens has negative focal power; a seventh lens, wherein the seventh lens has positive focal power; and the eighth lens has focal power, the first side surface of the eighth lens is a convex surface, and the second side surface of the eighth lens is a concave surface. According to the invention, at least one of the problems of difficulty in miniaturization, small field angle, poor imaging quality in a dark environment, poor temperature performance, serious aberration and poor light transmission capability of an optical lens in the prior art is solved.

The invention provides an optical lens, which comprises four lenses from the object side to the imaging surface along the optical axis: a first lens with negative focal power, the object side surface of which is a concave surface near the optical axis, and the image side surface of which is a concave surface; the image side surface of the second lens is a convex surface; the third lens has positive focal power, the object side surface of the third lens is a concave surface near the optical axis, and the image side surface of the third lens is a convex surface; the fourth lens has focal power, the object side surface of the fourth lens is a convex surface near the optical axis, and the image side surface of the fourth lens is a concave surface near the optical axis; wherein the maximum field angle FOV of the optical lens and the aperture value Fno meet the following conditions: 130 degree lt; an FOV / Fnot; 150 DEG C; the curvature radius R5 of the object side surface of the third lens and the curvature radius R6 of the image side surface of the third lens satisfy 0.1 lt; (R5-R6) / (R5 + R6) lt; and 0.8. According to the optical lens provided by the invention, the four lenses with specific focal power and specific surface type are adopted, so that the lens has one or more advantages of large aperture, large field of view, small distortion, miniaturization, high pixel and the like.

The invention provides a universal audio quality analysis method and system, and belongs to the technical field of audio, and the method comprises the steps: determining a standard audio quality index corresponding to a target scene; feature extraction is carried out on the target audio, multiple pieces of audio feature data are obtained, and the target audio is the audio in the target scene; and determining a target repair mode corresponding to the target scene based on the standard audio quality index and the multiple pieces of audio feature data, and repairing the to-be-transmitted audio based on the target repair mode. According to the universal audio quality analysis method and system provided by the invention, the accuracy of audio quality analysis can be improved.

The invention provides a projection lens, which comprises six lenses in total, and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from a projection surface to an image source surface, the surface of the projection side of the second lens is a convex surface, and the surface of the image source side of the second lens is a concave surface; the surface of the projection side of the third lens is a concave surface, and the surface of the image source side of the third lens is a convex surface; the surface of the projection side of the fourth lens is a concave surface; the surface of the image source side of the fifth lens is a convex surface; the surface of the projection side and the surface of the image source side of the sixth lens are convex surfaces; wherein the surface curvature radius R11 of the projection side of the sixth lens and the surface curvature radius R12 of the image source side of the sixth lens meet the following conditions:-0.8 lt; (R11 + R12) / (R11-R12) lt; and 0.1. According to the projection lens provided by the invention, the projection quality of the projection lens is improved through the reasonable configuration of the surface types of the lenses and the reasonable matching of the focal power.

The invention relates to a watermarking method based on mutual information screening and IGWO optimization, and the method comprises the following steps: 1, carrying out the attribute screening through a mutual information method, obtaining an attribute set which is highly related to the classification accuracy, determining an unimportant attribute set, and forming a complete attribute set after the mutual information screening; step 2, based on the attribute set screened by the mutual information attributes in the step 1, carrying out watermark embedding operation for an unimportant attribute set to obtain a watermark data set containing a watermark; and step 3, based on the watermark data set generated in the step 2, watermark data are classified through a decision tree model, and the watermark embedding strength and position are optimized by applying an IGWO algorithm. The method can effectively solve the problem of traceability responsibility of matched power grid service data.

The invention discloses an industrial weld defect detection method based on semantic segmentation. The method comprises the following steps: S1, obtaining an original weld image for training and related parameter information, carrying out binarization processing on the original image, storing a foreground region of the processed image, selecting a region with the maximum area to carry out rectangular shape conversion, and cutting and storing a rectangular region; s2, marking the cut rectangular region image, generating a weld defect image data set, cutting the image in the weld defect image data set by using an intelligent cutting method, and distributing redundant pixels generated by cutting; s3, constructing a semantic segmentation network model according to the data set generated in S2, focusing a defect region by using an attention mechanism, performing selective convolution calculation on the defect region, and training the semantic segmentation network model by using a loss function as an index; and S4, processing the weld seam image to be detected by using the semantic segmentation network model, and splicing and restoring the weld seam image to an original image size. According to the invention, the detection precision is improved, and image processing is not limited.

The invention discloses a distortion correction system and method for a laser self-space five-dimensional galvanometer. The distortion correction system comprises an offset module, a beam expanding module, a scanning module and a focusing module. All the modules are sequentially installed in the equipment according to a certain interval, and a laser beam at the tail end is focused on a working plane on a workbench through movement of an optical lens to achieve movement in a five-dimensional space, namely scanning in the X dimension and the Y dimension, movement of a focus in the Z dimension and deflection in the alpha dimension and the beta dimension are achieved. The offset module is used for enabling the light beam to deviate from the optical axis by a certain distance in the X dimension and the Y dimension; the beam expanding module is used for expanding the beam diameter; the scanning module is used for scanning the light beam in an XY plane; the focusing module is used for focusing the light beam and can ensure that the inclination angle of the focused light beam is small enough. Indirect correction of the processing pattern is adopted, different correction patterns are designed according to different dimensions of light beam movement, operation is convenient, and cost is low.

The invention belongs to the technical field of optical imaging, and relates to an image space telecentric lens for an imaging spectrometer and the imaging spectrometer. The lens comprises a first negative lens, a second negative lens, a first positive lens, a diaphragm, a second positive lens, a third negative lens, a third positive lens and a fourth positive lens which are sequentially and coaxially arranged in the light path propagation direction. Wherein the first negative lens is meniscus-shaped, and one side, close to the second negative lens, of the first negative lens is a concave surface; the second negative lens and the third negative lens are biconcave lenses; one side, close to the second negative lens, of the first positive lens is a concave surface; the second positive lens, the third positive lens and the fourth positive lens are all biconvex lenses. The multi-layer positive lens and the multi-layer negative lens are combined and alternated, the shape of each lens is limited, the negative lens is used for expanding light rays, and the positive lens is used for focusing and adjusting the light rays, so that the lens can still keep high imaging quality in a large view field range, aberration and distortion are reduced, and chromatic aberration of light rays with different wavelengths is effectively compensated.

The invention relates to the technical field of audio noise reduction, in particular to an audio noise reduction method and system based on deep learning. The method comprises the following steps: acquiring original audio and sound production equipment operation data associated with the original audio; invalid audio elimination is carried out on the original audio, so that effective audio is generated; carrying out audio time alignment on the effective audio so as to generate a preprocessed standard audio; performing audio output mode detection on the preprocessed standard audio and the sound production equipment associated with the original audio to generate single-equipment output audio and multi-equipment output audio; audio period regular segmentation is carried out on single-device output audio, and single-device short-period output spectrum data and single-device long-period output spectrum data are generated. According to the invention, through invalid audio elimination, time alignment, layered noise extraction and abnormal noise identification, the accuracy and real-time performance of the noise reduction effect are improved.

The invention discloses a zoom lens, which comprises a first lens group with positive focal power, a second lens group with negative focal power, a third lens group with positive focal power, a fourth lens group with positive focal power and a fifth lens group with focal power, and is characterized in that the first lens group, the third lens group and the fifth lens group are fixed groups; the first lens group comprises a first lens, a second lens and a third lens; the second lens group comprises a fourth lens, a fifth lens, a sixth lens and a seventh lens; the third lens group comprises an eighth lens, a ninth lens, a tenth lens, an eleventh lens, a twelfth lens and a thirteenth lens; the fourth lens group comprises a fourteenth lens, a fifteenth lens and a sixteenth lens; the fifth lens group comprises a seventeenth lens; the second lens group moves between the object side and the image side to realize continuous zooming between a wide-angle end and a telephoto end; and the fourth lens group moves between the object side and the image side so as to realize the compensation of the image surface position change in the zooming process.

The invention relates to a medium-focus large-aperture long-flange video lens with a focal length of 50mm. The medium-focus large-aperture long-flange video lens comprises a first lens group, an iris diaphragm and a second lens group which are sequentially arranged along a light incidence direction of a light path, wherein the first lens group serves as an immovable fixed group, the focal power is positive, and the first lens group is composed of lenses L11-L17 which are sequentially arranged in the light incidence direction of a light path and comprises two groups of doublet lenses and a group of triplet lenses; the second lens group serves as a movable focusing group, the focal power is positive, and the second lens group is composed of lenses L21-L27 which are sequentially arranged in the light incidence direction of the light path and comprises two groups of doublet lenses and a glass aspheric lens; the focal length value f1 of the first lens group and the focal length value f2 of the second lens group satisfy 0.47 lt; f2 / f1lt; and 0.56% of the total weight. The lens achieves a large clear aperture, high MTF resolution, small distortion and reduced achromatism, is short in total optical length, and meets a camera module matched with a long flange back focus.

The invention discloses an analog signal calibration test method and system applied to a constant-temperature and constant-humidity control cabinet. The system combines a high-precision signal generator and intelligent measurement equipment, automatically generates and measures analog signals, is internally provided with signal integrity protection, and ensures high-quality transmission of the signals. The system integrates data processing and analysis functions, analyzes data in real time by using an AI algorithm, calculates deviation, judges a calibration state, and tests communication capability. Through an advanced signal processing technology and material science, the system still keeps stability and signal integrity in an extreme environment. A unified control platform and a user interface are provided, parameter setting, data checking and system monitoring are facilitated, it is ensured that testing is efficient and accurate, the system is suitable for signal calibration testing of the constant-temperature and constant-humidity control cabinet, and the testing precision and the system reliability are remarkably improved.

The invention relates to an audio processing method, device and system and a storage medium, relates to the technical field of data processing, and aims to at least solve the problem of serious distortion of output audio in related technologies. The method comprises the following steps: inputting a to-be-processed audio into an audio conversion model, so as to adopt the audio conversion model to execute the following operations: calling an encoder to encode the to-be-processed audio into a target continuous encoding signal; quantizing the target continuous coded signal vector into a target discrete coded signal based on a preset codebook; calling a decoder to decode the target discrete coded signal into a target audio composed of continuous target output coded signals based on a preset codebook; wherein the preset codebook comprises an association mapping relation between a continuous coding signal and a discrete coding signal, and the audio conversion model is trained by taking reconstruction loss, codebook loss and retention loss of coding and decoding of a coder and a decoder as constraint targets; and outputting a target audio obtained after the operation of the audio conversion model is completed.

The invention relates to an optical lens which sequentially comprises a first lens, a second lens, a third lens and a fourth lens along the optical axis in the direction from the object side to the image side, 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, a fifth lens with negative focal power, a sixth lens with positive focal power, a seventh lens with negative focal power and an eighth lens with negative focal power are included. The effective focal length F12 of the combination of the first lens and the second lens and the effective focal length F of the optical lens meet the following relation: F12 / F is more than or equal to 3.95 and less than or equal to 9.6. The optical lens at least has one of the characteristics of large field of view, miniaturization, large target surface, high resolution, low distortion and the like.

The invention provides a laser confocal ocular surface image stitching method based on deep learning. Efficient and accurate image stitching is realized through unsupervised learning. Firstly, an ocular surface image is preprocessed, and a data set is constructed; then, a multi-scale feature pyramid is constructed by using a convolutional neural network, image features are automatically extracted and pre-aligned, and image alignment is optimized through global motion aggregation and local motion correction technologies. Thirdly, constructing a content fusion generative adversarial network which comprises a generator and a discriminator to smooth the fused image and generate a spliced image conforming to human eye perception; a staged training strategy is adopted, image alignment is optimized firstly, and then image smooth fusion is achieved. And finally, automatically finishing image alignment and fusion by using the trained network to obtain a seamless large-view confocal ocular surface image. According to the method, the splicing precision and robustness are improved, the method is suitable for image splicing in different environments, and the splicing success probability is remarkably improved.

The invention relates to the technical field of machine vision, in particular to an image segmentation method and system for liquid crystal screen display. The method comprises the following steps: acquiring basic data of the liquid crystal screen; performing screen response characteristic analysis according to the basic data of the liquid crystal screen to obtain screen response characteristic data; performing multi-scale image acquisition according to the basic data of the liquid crystal screen to generate multi-scale image data; performing characteristic classification on the liquid crystal display according to the screen response characteristic data, and performing edge compensation analysis on the multi-scale image data to obtain edge characteristic compensation data; acquiring real-time data of the touch screen; and performing touch interference identification analysis on the real-time data of the touch screen according to the edge feature compensation data to generate touch interference mask data. By analyzing the screen response characteristics and performing edge compensation analysis, the phenomenon of edge blurring caused by liquid crystal response time limitation is reduced, and the accuracy of edge detection is improved.

The invention discloses an optical lens and imaging equipment, the optical lens sequentially comprises a first lens, a second lens with focal power, a third lens, a fourth lens with focal power, a fifth lens with focal power and a sixth lens with focal power from a first side to a second side along an optical axis, the first lens has negative focal power, the second lens has focal power, the third lens has focal power, the fourth lens has focal power, the fifth lens has focal power, and the sixth lens has focal power. The first side surface and the second side surface are concave surfaces; the third lens has positive focal power, and the first side surface of the third lens is a convex surface.

The invention belongs to the technical field of optical communication chips, and particularly relates to an HEMT (High Electron Mobility Transistor)-driven near ultraviolet bidirectional optical communication monolithic integrated chip with the wavelength of 365 nm and a preparation method thereof. Functions of an optical transmitter, an optical receiver and a driver are integrated into one chip, light emitted by a transmitting end is coupled into an optical waveguide and is detected by a photoelectric detector, an optical signal is converted into an electric signal, information transmission in the chip is completed, and a bidirectional optical communication link can be constructed without two sets of optical transmitters and optical receivers; the DBR Bragg reflection layer is adopted to reflect emergent light in all directions back to the waveguide of the straight waveguide area, so that the emergent light is transmitted to a receiving end along the waveguide of the straight waveguide area, by designing the material and period of the DBR, about 70% of the emergent light can be reflected, and the detection accuracy is improved; the integrated HEMT drive reduces the size and complexity of the whole circuit, the HEMT can still keep good linear performance under high current, distortion is reduced, and the stability of LED light output is ensured.

The utility model discloses an optical lens. The utility model relates to a zoom lens, which sequentially 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 negative focal power, a fifth lens with negative focal power, a sixth lens with positive focal power and a seventh lens with negative focal power from an object side to an image side along an optical axis, the first lens has positive focal power, the eighth lens has positive focal power, the ninth lens has positive focal power, the tenth lens has negative focal power, and the eleventh lens has positive focal power.

According to the multi-object-distance and low-distortion lens for machine vision and the camera device, the lens comprises an optical system, the optical system comprises a first lens group, an aperture diaphragm and a second lens group, the first lens group comprises a first lens, a second lens and a third lens, and the second lens comprises a second lens and a third lens. The second lens group comprises a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens which are arranged on the same optical axis from the object space to the image space; the first lens is a biconvex lens with positive focal power, the second lens is a biconvex lens with positive focal power, the third lens is a biconcave lens with negative focal power, the fourth lens is a biconvex lens with positive focal power, the fifth lens is a biconcave lens with negative focal power, the sixth lens is a meniscus lens with negative focal power, and the seventh lens is a meniscus lens with positive focal power. And the eighth lens is a biconvex lens with positive focal power. The lens provided by the invention has the advantages of large object distance range, low distortion and high resolution.

The invention relates to an industrial lens which sequentially comprises a first lens group with positive focal power, a second lens group with negative focal power and a third lens group with positive focal power along an optical axis from an object side to an image side, the first lens group and the third lens group are fixed lens groups, and the second lens group is a focusing group; the first lens group 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 negative focal power and a fifth lens with positive focal power; the second lens group comprises a sixth lens with positive focal power and a seventh lens with negative focal power; the third lens group comprises an eighth lens and a ninth lens which are opposite in focal power, a tenth lens with positive focal power and an eleventh lens with negative focal power. The industrial lens has at least one of the characteristics of low distortion, high illumination, high resolution, wide focusing object distance range, no virtual focus in the temperature range of-40 DEG C to + 80 DEG C and the like.

According to the multi-object-distance, low-distortion and high-definition machine vision lens and the camera device provided by the invention, the lens comprises an optical system, and the optical system comprises a first lens group, an aperture diaphragm and a second lens group which are arranged on the same optical axis from an object space to an image space; the first lens group comprises a first lens, a second lens, a third lens and a fourth lens which are arranged on the same optical axis from the object side to the image side, and the second lens group comprises a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens and a tenth lens which are arranged on the same optical axis from the object side to the image side. According to the invention, the imaging effects of high image quality, high accuracy and low distortion can be presented under the condition of satisfying multiple object distances.

The zoom lens comprises a focusing lens group, a zoom lens group and a fixed lens group which are sequentially arranged from an object plane to an image plane along an optical axis, the focusing lens group has negative focal power, the zoom lens group has positive focal power, and the fixed lens group has positive focal power; the first lens has negative focal power, the second lens has negative focal power or positive focal power, and the third lens has negative focal power; the fourth lens has positive focal power; the fifth lens has negative focal power, the sixth lens has positive focal power, the seventh lens has negative focal power, the eighth lens has positive focal power, the ninth lens has negative focal power or positive focal power, the tenth lens has negative focal power, and the eleventh lens has positive focal power. The zoom lens can meet the imaging requirement under the full wave band, has the advantages of being small in size and small in distortion, and meets the use requirements of security and protection.

The invention belongs to the technical field of voice noise reduction. The invention provides an edge end real-time voice noise reduction method. According to the embodiment of the invention, pre-emphasis, framing and windowing processing is carried out on the input voice signal, so that the high-frequency component of the signal is improved and the distortion of the signal is reduced. And performing fast Fourier transform on the preprocessed input voice signal to convert a time domain signal into an original frequency domain signal. And calculating the Mel frequency cepstrum coefficient of the original frequency domain signal to extract the MFCC characteristic parameter of the speech. Noise estimation is performed on the MFCC characteristic parameters by using the lightweight separable convolutional neural network, so that the parameter quantity and the calculation quantity are reduced, and efficient noise estimation is realized. And performing adaptive iterative Wiener filtering by using the generated noise estimation, and gradually eliminating noise in the voice signal to obtain a filtered frequency domain signal. And inverse fast Fourier transform is carried out on the filtered frequency domain signal, and a time domain signal is recovered. And outputting a time domain signal which is a voice signal after noise reduction.

The embodiment of the invention discloses an eyepiece lens. The eyepiece lens comprises a diaphragm, a first lens, a second lens, a third lens, a fourth lens and a fifth lens which are sequentially arranged from an observation side to a display side along an optical axis, the first lens is a glass spherical lens with positive focal power, the second lens is a glass spherical lens with positive focal power, the third lens is a glass spherical lens with negative focal power, the fourth lens is a glass spherical lens with negative focal power, and the fifth lens is a glass spherical lens with positive focal power. According to the embodiment of the invention, an all-glass 5G structure is designed and adopted, through matching of lens materials and reasonable distribution of focal power, the eyepiece lens with long exit pupil distance, small distortion, small aberration and low cost is realized, the exit pupil distance reaches 48mm, and the distortion is less than 1.5%.

The invention relates to an in-ear earphone with a caisson structure, and the earphone comprises a front cavity shell which is provided with a front cavity and a sound outlet communicated with the front cavity, and the sound outlet is sleeved with an earcap; the rear cavity shell is provided with a rear cavity communicated with the front cavity, a caisson structure part is arranged in the rear cavity and comprises an upper-layer caisson structure, a middle-layer caisson structure and a lower-layer caisson structure which are sequentially connected, the middle-layer caisson structure is located on the outer side of the upper-layer caisson structure, and the diameter of the middle-layer caisson structure is larger than that of the upper-layer caisson structure; the lower-layer caisson structure is located outside the middle-layer caisson structure and is larger than the middle-layer caisson structure in diameter; the sound production unit is arranged in the front cavity and the rear cavity; the caisson structure part is arranged in the rear cavity, the cavity is formed between the caisson structure part and the sound production unit, upward diffusion of sound is avoided, the sound gathering effect is achieved by scientifically applying the acoustic phase inversion hole principle, and meanwhile in order to enhance low-frequency response and improve sound quality, the phase inversion hole enables the bass to be cleaner and reduces distortion by reducing back wave reflection of the bass unit.