39results about How to "Achieve precise focus" patented technology

The invention relates to a ranging device, which comprises a body, a receiving lens, a first locking wheel, a second locking wheel, a movable plate and a receiving component, wherein the body is provided with a first end and a second end; the first end is opposite to the second end, and the second end is provided with at least one guide rod; the receiving lens is connected to the first end of the body; the first locking wheel and the second locking wheel are connected to the second end of the body in a rotary mode; the movable plate is sleeved on the guide rod of the second end of the body in a movable mode and is arranged between the first locking wheel and the second locking wheel; and the receiving component is connected to the movable plate and is used for receiving light beams received by the receiving lens. The movable plate moves through the rotation of the first locking wheel and the second locking wheel so as to drive the receiving component to move on an optical axis.

An adjustable focus high-power focusing lens, which relates to a focusing lens to solve the problem that the large-aperture focusing lens of the existing high-power laser cannot be moved accurately, and cannot achieve precise focusing and focus multiple beams of high-energy lasers on a small section of space There is a difficult problem in memory, which includes the lens shield assembly, lens replacement unit assembly, X-position adjustment assembly, Y-position adjustment assembly, and Z-position adjustment assembly; the lens shield assembly is installed on the lens replacement unit assembly, and the lens replacement The unit assembly is installed on the X-direction position adjustment assembly, the X-direction position adjustment assembly is used to drive the lens drive assembly to move in the X direction, the X-direction position adjustment assembly is installed on the Y-direction position adjustment assembly, and the Y-direction position adjustment assembly is used for In order to drive the X-direction position adjustment component to move in the Y direction, the Y-direction position adjustment component is installed on the Z-direction position adjustment component. The invention is used for focusing of a focusing lens.

The invention discloses a range migration imaging method for a shift-invariant bistatic SAR. The method of the invention is based on the bistatic SAR two-dimensional spectrum of the generalized Loffeld transform, and linearly expands the phase of the spectrum along the shortest slant distance of the receiving station to derive the Stolt frequency. The transformation expression, through which the residual range unit migration correction, residual secondary range compression and residual azimuth compression are completed, and the spatial domain linearization and frequency domain linearization of the residual phase are realized, thereby realizing the accurate shift-invariant bistatic SAR focus. Compared with the existing shift-invariant bistatic SAR distance migration algorithm, the method of the invention has simple form, high precision and high operation efficiency.

The invention discloses an imaging processing method for a coprime sampling satellite borne SAR, which belongs to the field of signal processing. The imaging processing method comprises the followingsteps: after obtaining imaging parameters, echo data and a coprime sampling matrix, firstly carrying out the range-wise pulse compression on a coprime sampling SAR echo signal, then starting from a first range gate, calculating the number of range gates spanned by the range gate echo signal according to Doppler parameters of each range gate, constructing a corresponding sparse dictionary, and intercepting a two-dimensional observation signal on the basis of the range gate echo signal, and finally reconstructing the two-dimensional observation signal by using an improved sparse reconstruction algorithm adaptive to the sparsity of the two-dimensional observation signal, thereby obtaining backscatter information of a scene target. By adopting the imaging processing method for the coprime sampling satellite borne SAR, the influence of the change of the imaging parameters along with the range door for the sparsity reconstruction can be compensated, the full-scene accurate focusing can be realized, the imaging processing under a coprime sampling working mode can be realized, the imaging accuracy is high, and the practicability is high.

The invention discloses a bistatic forward-looking SAR frequency-domain imaging method based on spectrum optimization modeling, comprising the following steps: S1, performing data preprocessing to obtain echo signals; S2, performing two-dimensional Fourier transform on the echo signals, Establish the optimal two-dimensional spectrum model of the point target response of the system, and solve the precise two-dimensional spectrum of the point target response through the differential evolution optimization method; S3, carry out rough matching and focusing on the precise two-dimensional spectrum of the point target response; Range-frequency transform; S5. Perform a two-dimensional inverse Fourier transform on the two-dimensional frequency spectrum after the range-frequency transform to obtain a final complex image. The present invention overcomes the problem that the existing imaging algorithm cannot deal with the non-linear spatial variation of bistatic forward-looking SAR range, obtains the accurate two-dimensional spectrum of bistatic forward-looking SAR through the differential evolution optimization method, and obtains the accurate two-dimensional spectrum according to the point target response The imaging processing of the echo signal in the two-dimensional frequency domain can realize the precise focusing of the raw data of the bistatic forward-looking SAR.

The invention relates to a corneal curvature measuring device based on a telecentric optical path system, which is composed of an objective lens device, a light point collimation device, a target ring lighting device, a target ring device, a monitoring spectroscopic mirror device, a monitoring system device and a base plate. The device includes an objective lens holder, an objective lens barrel and an objective lens; the spot collimating device includes a spot collimating lens barrel, a light source circuit board, a light emitting diode, a scattering sheet, an aperture diaphragm and a collimating lens; the target ring illuminating device includes a target Ring lighting circuit board and at least three lighting light-emitting diodes; the target ring device includes a target ring fixing support, target ring and target ring protection sheet; the monitor optical analysis mirror device includes a monitoring optical analysis mirror seat and a monitoring optical analysis mirror; the monitoring The system device includes a monitoring fixed support, a monitoring lens barrel, a monitoring lens and a diaphragm pressure cylinder. The invention greatly improves the focusing speed and the measurement accuracy of the corneal curvature of the fully automatic computer optometry instrument.

The present invention provides an image correction method, device, electronic equipment, and computer-readable storage medium. The method obtains the offset of the camera when the camera shakes; wherein, the structured light module has Optical image stabilization mode; adjust the deflection angle of the projector according to the calibration function and the offset of the camera, and simultaneously acquire the depth image collected by the camera; acquire the deflection angle according to the offset and the deflection angle Reference depth information of the depth image; correcting the depth image according to the reference depth information. Solved the problem of large errors in the depth information obtained by the camera during the process of taking pictures or previewing with the structured light module. By using the reference depth information to correct the depth image, the depth image acquired by the structured light module can be corrected. Improve the accuracy of depth information acquisition, and then achieve precise focusing on the shooting object.

The invention discloses a high squint SAR curvilinear path wavenumber domain imaging method based on a slope distance model, comprising: building a high squint SAR (Synthetic Aperture Radar) geometric model on a curvilinear path, selecting any point target Q, successively calculating an instantaneous slant distance R (ta) from an SAR aircraft to the point target Q, and a hyperbola instantaneous slant distance Re(ta) from the SAR aircraft to the point target Q, furthermore calculating the instantaneous slant distance R (X) from a high squint SAR aircraft on a curvilinear path to a point target, calculating distance frequency domain orientation time domain echo signals S (Kr, X) of a high squint SAR on a curvilinear path, furthermore successively calculating orientation time domain echo signals S<^> (Kr, X) of a high squint SAR on a curvilinear path after distance pulse pressure, and orientation time domain echo signals S (Kr, Kx) of a high squint SAR on a curvilinear path after fast fourier transform (FFT), setting an orientation resampling coefficient Kx-new, calculating orientation time domain echo signals S (Kr, Kx-new) of a high squint SAR on a curvilinear path after orientation resampling, furthermore calculating echo signals of a high squint SAR on a curvilinear path under a two-dimensional beam spectrum, successively performing range direction IFFT and azimuth IFFT, and obtaining high squint SAR imaging under a slope distance model.

The invention discloses a double-station frequency-modulation continuous wave synthetic aperture radar imaging method which particularly includes the steps of conducting dechirp processing on echo signals, removing residual video phases, conducting distance direction time-frequency replacement and azimuth Fourier transformation, conducting rough matching focusing to remove space invariant items of the phases, and conducting wave number domain transformation to remap the distance direction frequency. By means of the double-station frequency-modulation continuous wave synthetic aperture radar imaging method, instantaneous slant distance changes caused by continuous motion of a transmitting-receiving station within the pulse duration time are considered, Doppler parameters in echoes, distance migration and high-order coupling linear space variant characteristics are adopted, point-target echo two-dimensional frequency spectrum airspace linearization is achieved, and the point-target echo two-dimensional frequency spectrum airspace problem is solved.

The invention discloses a camera automatic focusing control method focused on a moving target. The camera automatic focusing control method comprises the steps of: 1, calibrating a moving target position region in a scene by adopting a background subtraction-based moving target detection algorithm; and 2, realizing automatic focusing of a camera lens for the calibrated moving target by adopting a target gray gradient-based automatic focusing control algorithm after determining a camera focusing region and a focusing target, wherein the step 1 comprises the following sub-steps of: 1.1, carrying out Gaussian smoothing filter preprocessing; 1.2, modeling a Gaussian background model; 1.3, extracting a target foreground region; 1.4, updating the Gaussian background model; and 1.5, carrying out mathematical morphological processing on the target foreground region; and the step 2 comprises the sub-steps of: 2.1, extracting a moving target focusing region; 2.2, calculating a focusing evaluation function; and 2.3, carrying out focusing control.