Device and method for detecting drill-borne video imaging resolution

Abstract

The invention provides a device and method for detecting drill-borne video imaging resolution, and relates to the technical field of optical measurement, and the device comprises a transparent pressure-resistant window with a composite target inside, a coaxial programmable illumination assembly, an IMU, an environment sensor, an imaging assembly and a control processing unit. Synchronously acquiring composite target image data, IMU data and environment sensing data, and performing time alignment on the data; calculating and measuring an MTF curve, a motion MTF, a medium MTF and a pixel aperture MTF based on a composite target image, IMU data, environment sensing data and an image obtained by an imaging assembly; stripping the moving MTF, the medium MTF and the pixel aperture MTF from the measured MTF curve to obtain an optical intrinsic MTF; and detecting the drill-borne video imaging resolution according to the measured MTF and the optical intrinsic MTF. According to the invention, the measurement of the effective resolution and the intrinsic optical resolution of while-drilling video imaging under complex working conditions is realized.

Description

Technical Field

[0001] This invention relates to the field of optical measurement technology, and in particular to an apparatus and method for detecting the resolution of drill-mounted video imaging. Background Technology

[0002] Drilling video is used for structural identification and risk assessment in geothermal, oil and gas, mining, and urban underground spaces. Common operating conditions include high-speed rotation, strong vibration, turbidity / absorption, high temperature and pressure, and low light. Traditional resolution testing is mostly performed in static, clean media, and the resulting metrics are difficult to represent the "effective resolution" in the field. Furthermore, there is a lack of methods to separate motion blur and medium scattering / absorption from the overall degradation, making it impossible to pinpoint performance bottlenecks and provide optimization paths. The applicability of methods such as the ISO 12233 bevel method and USAF targets is limited in strong rotation and turbid environments, and on-site quality control and consistency calibration remain challenging. Summary of the Invention

[0003] The purpose of this invention is to address the difficulty in determining the effective resolution and intrinsic optical resolution of drill-mounted video imaging under conditions of rotation, vibration, and turbidity. A method and apparatus for detecting the resolution of drill-mounted video imaging are proposed, the apparatus comprising: Internally, it has a transparent pressure-resistant window for a composite target, a coaxial programmable illumination assembly, an IMU, an environmental sensor, an interface module, an imaging assembly, and a control and processing unit; Environmental sensors include: turbidity / transmittance sensors, illuminance sensors, temperature sensors, and pressure sensors; The composite target is a concentric multi-ring composite target. The outer ring is a hypotenuse target, the middle ring is a Siemens star target, and the inner ring is a circular observation and imaging area. There is a ring-shaped isolation area between the middle and outer rings. The XOY pixel axis is constructed with the center of the inner ring as the origin. The outer ring has four hypotenuses, with the two endpoints of the hypotenuses on the outer circle of the outer ring. Perpendicular segments are drawn from the origin to the hypotenuses, satisfying the following conditions: the four perpendicular segments are of equal length, and their directions are clockwise: positive X-axis, negative X-axis, positive Y-axis, and negative Y-axis. Angle; Siemens star sector count is 24~72; Coaxial programmable lighting components are used to provide controllable lighting; The interface module is used for power and data transmission; IMU data, environmental sensor data, images acquired by the imaging components, and composite target images are processed by the control processing unit to obtain the imaging resolution.

[0004] This invention also proposes a method for detecting the resolution of drill-mounted video imaging, implemented based on the aforementioned apparatus for detecting the resolution of drill-mounted video imaging, the method comprising: S1. Synchronously acquire composite target image data, IMU data and environmental sensor data, and perform time alignment on the data; S2. Calculate and measure the MTF curve based on the composite target image; Reconstructing image plane trajectory and calculating motion MTF based on IMU data; Establish media MTF based on environmental sensor data; Pixel aperture MTF is established based on the images obtained by the imaging components; S3. Separate the motion MTF, medium MTF and pixel aperture MTF from the measured MTF curve to obtain the optical intrinsic MTF; S4. Detect the resolution of the drilling video imaging based on the measured MTF and optical intrinsic MTF.

[0005] Furthermore, the formula for the measured MTF obtained using the Siemens star target is:

[0006]

[0007]

[0008]

[0009]

[0010] in, Indicates radial frequency as The MTF was measured at that time. This indicates the radial frequency corresponding to the circumference of a circle with radius r. To measure the polar coordinate radius of the star marker, and These are the inner and outer radii of the central ring where the Siemens star is located. Represents the phase-locked cosine component. The circumference of a circle with radius r is at an angle grayscale at that location M represents the circumferential angle, and M represents the black-and-white logarithm of the Siemens star target. Indicates adjustment system, Represents the phase-locked sinusoidal component. This represents the average brightness on the circumference of a circle with radius r.

[0011] Furthermore, the MTF measured using the SFR hypotenuse method based on the hypotenuse target is given by the following formula:

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

[0018] in, Indicates direction The measured MTF, This represents the k-th spatial frequency, where k represents the frequency index. Represents the discrete spectrum. Indicates Fourier transform, This represents the windowed line spread function, where N represents the number of sampling points. Indicates the normal bin step size. This represents the SFR oversampling factor, where p represents the pixel pitch. Represents the window function. Represents the line spread function. This represents the average gray level per box as indicated by the edge spread function. This represents the set of pixel indices contained in the nth bin. Indicates the first i 1 pixel, Indicates the first i One-dimensional coordinates from the center of each pixel to the direction of the hypotenuse normal. Indicates the first i The coordinates of the center of each pixel This represents the signed perpendicular distance from the origin to the hypotenuse.

[0019] Furthermore, the motion MTF can be expressed by the formula:

[0020]

[0021] in, The motion MTF at frequency f is represented. This indicates the exposure time, where i represents the imaginary unit. This represents the equivalent trajectory of the image plane at time t. This represents the initial image shift, and t represents time. Indicates the image plane in Instantaneous velocity at time.

[0022] Furthermore, the medium MTF is expressed by the formula:

[0023]

[0024] in, This represents the medium MTF at frequency f. Indicates the equivalent scattering standard deviation. and The coefficients represent the fit, and NTU represents turbidity. Indicates the effective optical path.

[0025] Furthermore, the pixel aperture MTF is expressed by the formula:

[0026] in, express Pixel aperture MTF at that location Let f represent the two components of the two-dimensional spatial frequency vector f on the image plane along the x and y axes, and p represent the pixel size.

[0027] Furthermore, the optical intrinsic MTF is expressed by the formula:

[0028] in, This represents the optical intrinsic MTF at frequency f after compensation. This represents the measured MTF at frequency f. This represents the medium MTF at frequency f after compensation. This represents the motion MTF at frequency f after compensation. The pixel aperture MTF is represented at a frequency of f.

[0029] The beneficial effects of the technical solution provided by this invention are: This invention constructs a device for detecting the resolution of drill-mounted video imaging, including an optical window with a composite target, an inertial measurement unit, environmental sensors such as turbidity / transmittance sensors, an imaging component, and a control and processing unit. Based on Siemens star radial phase-locked loop and circular inclined plane SFR, the measured MTF curve is obtained. The inertial measurement unit, environmental sensors, and imaging component are used to obtain the motion MTF, medium MTF, and pixel aperture MTF. The motion MTF, medium MTF, and pixel aperture MTF are then separated from the measured MTF. The device outputs indicators such as MTF50 / MTF10, angular resolution, line pairs per degree, equivalent exposure time, temporal resolution, and blur index MBI. It achieves dual output of intrinsic MTF and effective MTF, solving the problem of difficulty in measuring the effective resolution and intrinsic optical resolution of drill-mounted video imaging under rotating, vibrating, and turbid media conditions. This provides an executable optimization basis for illumination, rotation speed, wavelength, focusing, and algorithm parameters. Attached Figure Description

[0030] Figure 1 This is a structural diagram of a device for detecting the resolution of drilling video imaging according to an embodiment of the present invention; Figure 2 This is a composite target diagram according to an embodiment of the present invention; Figure 3 This is a flowchart of a method for detecting the resolution of a drilling-mounted video imaging system according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure and fluid circulation of the spin-forming simulation calibration chamber according to an embodiment of the present invention. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0032] A structural diagram of a device for detecting the resolution of drilling-mounted video imaging according to an embodiment of the present invention is shown below. Figure 1 ,include: Internally, it features a transparent pressure-resistant window for a composite target, a coaxial programmable illumination assembly, an inertial measurement unit (IMU), an environmental sensor, an imaging assembly, and a control and processing unit.

[0033] refer to Figure 2 , Figure 2 This is a composite target image according to an embodiment of the present invention. The composite target is a concentric multi-ring composite target, with the outer ring being a beveled target, the middle ring being a Siemens star target, and the inner ring being a blank circular observation imaging area. The radius of the inner ring is... The outer radius of the middle ring is The radius range of points within the middle ring is The outer radius of the outer ring is The radius range of points within the outer ring is Radius range The ring shape forms an isolation zone to prevent interference. , Smaller than the optical window radius, , , , The actual length is selected according to the requirements, taking into account the size of the cover plate, the imaging field of view, and the requirements of the detection target.

[0034] With the center of the inner ring as the origin, the horizontal direction is the X-axis, and the vertical direction is the Y-axis, constructing the XOY pixel axis. Multiple straight hypotenuses are arranged within the outer ring, with the hypotenuses arranged as follows: starting from the origin O, rotating clockwise in all four directions (positive X-axis, negative X-axis, positive Y-axis, and negative Y-axis) around the origin as the center of rotation. Arrange line segments of length d in each of the four directions. The four line segments are in The endpoints inside are respectively , , , ,go through , , , Draw perpendicular lines to the four endpoints respectively , , , straight line , , , ,straight line , , , The line segments intercepted within the outer ring are four hypotenuses. These four hypotenuses divide the outer ring into two parts: one part is the closed region formed by the four hypotenuses and the outer ring, and the other part is the four smaller regions formed by the four hypotenuses and the outer circle of the outer ring. The two parts are black and white, forming black and white hypotenuses.

[0035] The Siemens star target in the central ring consists of multiple sets of radially radiating black and white stripes, with 24 to 72 Siemens star sectors (preferably 36 to 48), used to evaluate the modulation transfer function of the optical system. All target structures are processed onto the surface of quartz glass using photolithography to ensure geometric accuracy and contrast stability under high pressure and high turbidity environments.

[0036] The coaxial programmable lighting unit is a ring-shaped LED array that supports short-pulse flicker and phase-shift sinusoidal / multi-frequency modulation, and integrates luminous flux and spectral / color temperature monitoring. Brightness and lighting mode control can be achieved through programming. Optimal lighting parameters (such as brightness and zone mode) can be preset and recalled with a single button or switched automatically, greatly improving production efficiency and inspection consistency.

[0037] The inertial measurement unit (IMU) includes a three-axis gyroscope and accelerometer, which are hardware-level synchronized with exposure gating and illumination triggering.

[0038] Environmental sensors include: turbidity / transmittance sensors, illuminance sensors, temperature sensors, and pressure sensors, etc.

[0039] The imaging components include a lens and an image sensor, support global / roll shutter, and are compatible with the visible and near-infrared spectral bands.

[0040] The interface module is used for power and data transmission.

[0041] The control processing unit provides system clock, timing and synchronization control, performs image preprocessing, MTF (Modulation Transfer Function) estimation, motion PSF and medium transport inversion, and index output. IMU data, environmental sensor data, images acquired by the imaging components, and composite target images are processed by the control processing unit to obtain the imaging resolution.

[0042] This invention also proposes a method for detecting the resolution of drilling-mounted video imaging, the flowchart of which is shown below. Figure 3 Based on the above-mentioned device for detecting the resolution of drilling-mounted video imaging, the method includes: S1. Synchronously acquire composite target image data, IMU data, and environmental sensor data, and perform time alignment on the data.

[0043] Specifically, it includes: S11, Preset lighting sequence: The timing sequence for one test is... Where k is the illumination sequence index and N is the frame number. The exposure gate function for each frame is... The equivalent exposure time is Exposure gate function The time window for determining the averaging of motion directly affects the motion fuzzy kernel.

[0044] S12. Synchronously acquire composite target images, IMU data (including triaxial angular velocity and acceleration), and environmental sensor data (including turbidity, transmittance, temperature, illuminance, and pressure).

[0045] S13. Align all data to the same timeline, minimizing synchronization jitter. .

[0046] S2. Calculate two measured MTF curves based on composite target images. The MTF is calculated using two methods: Siemens star radial lock-to-phase comparison and hypotenuse SFR.

[0047] MTF can be measured at various angles by comparing and calculating the radial lock phase using Siemens star markers. The formula for calculating MTF using the radial lock phase phase using Siemens star markers is: The correspondence between radial frequency and radius r is as follows:

[0048] Phase-locked detection of the fundamental frequency term is used to suppress illumination inhomogeneity and slow background:

[0049]

[0050]

[0051]

[0052]

[0053] in, Indicates radial frequency as The MTF was measured at that time. This indicates the radial frequency corresponding to the circumference of a circle with radius r. To measure the polar coordinate radius of the star marker, and These are the inner and outer radii of the ring containing the Siemens star, respectively. In actual calculations, a narrow ring [r-Δr / 2, r+Δr / 2] is used to improve robustness, where r is the median diameter of the narrow ring and Δr is a very small value. Represents the phase-locked cosine component. The circumference of a circle with radius r is at an angle grayscale at that location M represents the circumferential angle, and M represents the black-and-white logarithm of the Siemens star target. Indicates adjustment system, Represents the phase-locked sinusoidal component. This represents the average brightness on the circumference of a circle with radius r.

[0054] The MTF measured using the SFR (Slanted Radius) method based on a slanted target allows for the separate detection of horizontal and vertical resolution and anisotropy in four directions. The multi-directional slanted edges have a slight tilt angle to the pixel axis on the pixel grid. Each time a pixel is crossed along the edge's normal coordinate, a sub-pixel-level step is generated, forming an oversampling sequence of edge grayscale. Pixel grayscale values ​​are aggregated according to normal coordinates to form an edge spread function (ESF). The pixel grayscale values ​​are binned and averaged according to the hypotenuse normal coordinates to obtain a one-dimensional sequence E[n]. Then, the difference is calculated to obtain a line spread function (LSF), and the discrete approximation sequence is L[n]. After windowing the LSF, an FFT (Fast Fourier Transform) is performed. The windowed LSF is then processed. Perform an FFT and normalize the amplitude at zero frequency to obtain the SFR / MTF. Then, normalize the amplitude at zero frequency to obtain the measured MTF curve in that direction. The frequency coordinates are divided into bin steps based on the normal direction. Decision, and And from the angle of inclination The pixel pitch p is determined. Finally, the obtained directions are... Corresponding , and By dividing, the intrinsic optical MTF in that direction can be decomposed, which can be used for index calculation and control write-back.

[0055] The SFR oversampling factor is:

[0056] in, This represents the SFR oversampling factor.

[0057] The angle of inclination of the hypotenuse relative to the pixel axis is The "equivalent displacement" step size of the pixel center along the hypotenuse normal is approximately:

[0058] in, The normal bin step size is represented by p, which represents the pixel pitch.

[0059] Due to slight distortions in fabrication / imaging, setup errors, shutter distortion during rolling, or non-perfectly straight boundaries, within a small ROI (Region of Interest) frame, the slanted straight line is approximately a straight line at the inner boundary of the ROI. l The least-squares fit of the boundary points within the ROI is performed using the Hessian normal form:

[0060] in, Let x be the unit vector normal to the hypotenuse, and let x represent the image plane coordinates. Indicates the distance from the origin to the line. l The signed perpendicular distance, It is the normal angle, which is perpendicular to the positive X-axis direction. , 90° , 180° , 270° Values ​​are taken from four angles.

[0061] Calculate pixel center One-dimensional coordinates of the normal to the hypotenuse:

[0062] in, This represents the one-dimensional normal coordinate from the i-th pixel to the edge.

[0063] according to Binning and tangential averaging yield the edge spread function (ESF):

[0064] in, The edge spread function shows the average gray level per box. This represents the set of pixel indices contained in the nth bin. Let represent the i-th pixel. Then, for... Perform appropriate smoothing and 0-1 normalization (to suppress noise and facilitate differentiation and normalization).

[0065] right By performing differential differentiation and windowing to obtain the LSF, leakage can be suppressed.

[0066] in, Represents the line spread function. This represents the windowed line spread function, where N represents the number of sampling points. This represents a window function. Window functions can be Hamming or Blackman windows, and are used to reduce spectral leakage due to finite lengths.

[0067] Performing a Fast Fourier Transform (FFT) yields the MTF for the direction θ:

[0068]

[0069] in, Indicates direction The measured MTF, This represents the k-th spatial frequency, where k represents the frequency index. Represents the discrete spectrum. This represents the Fourier transform.

[0070] The measured directional MTF was obtained in each direction of the multi-directional hypotenuse. The next step will be to use a transfer function consistent with the direction. , and right By performing decomposition / compensation, the intrinsic optical curve in this direction can be obtained. Then calculate , Iso-directional caliber.

[0071] The image plane trajectory is reconstructed based on IMU data, and the motion MTF is calculated. The motion MTF is expressed by the formula:

[0072]

[0073] in, The motion MTF at frequency f is represented. This indicates the exposure time, where i represents the imaginary unit. This represents the equivalent trajectory of the image plane at time t. This represents the initial image shift, and t represents time. Indicates the image plane in Instantaneous velocity at time.

[0074] The medium MTF is established based on environmental sensor data. The medium MTF is expressed by the formula:

[0075]

[0076] in, This represents the medium MTF at frequency f. Indicates the equivalent scattering standard deviation. and denoted by , NTU represents turbidity, and L represents the effective optical path.

[0077] The pixel aperture MTF is established based on the image obtained by the imaging component. The pixel aperture MTF is expressed by the formula:

[0078]

[0079] in, express Pixel aperture MTF at that location This represents the two components of the two-dimensional spatial frequency vector f in the image plane along the x and y axes. p represents the pixel size. Let p represent the two components on the x-axis and y-axis, respectively.

[0080] S3. Each component within the system has an associated MTF, contributing to the overall MTF of the system. The final MTF of the system is the product of the MTF curves of all its components, obtained through decomposition as the "intrinsic" curve. Under numerical stability (band-limited and regularized), the motion MTF, medium MTF, and pixel aperture MTF are separated from the measured MTF curves to obtain the optical intrinsic MTF, which is expressed by the formula:

[0081] in, This represents the optical intrinsic MTF at frequency f after compensation. This represents the measured MTF at frequency f. This represents the medium MTF at frequency f after compensation. This represents the motion MTF at frequency f after compensation. This represents the pixel aperture MTF at frequency f. To avoid amplifying noise at high frequencies with small denominators, compensation is only applied to... The frequency band >0.1 is used, and Tikhonov regularization is applied.

[0082] S4. Detect the resolution of the drilling video imaging based on the measured MTF and optical intrinsic MTF.

[0083] Read the "resolution index" from the curve and convert the units. On the selected MTF curve (measured MTF or optical intrinsic MTF), solve for the frequency point f that makes the MTF reach 0.5 / 0.1. 50 and f 10 f 50 and f 10 Used as a resolution indicator; the higher the value, the higher the resolution. 50 Most relevant to subjective sharpness / sharpness, often used as the resolution aperture. 10 It is closer to the "limit of resolution / bandwidth".

[0084] On the selected curve (effective or intrinsic), find the frequency points that make the MTF reach 0.5 / 0.1:

[0085] Two types of curves and reading points: The star indicates the radial (average in all directions) curve: and obtain The four directions of the hypotenuse: and obtain The resolution index of the multi-directional hypotenuse is averaged in terms of direction.

[0086] Perform image plane / object plane / viewpoint conversions as needed:

[0087] in, Represents the object / target plane , Represented on the image plane / sensor plane m is the image magnification (image size / object size); p is the pixel size (mm / px); For horizontal pixels; H FOV 1 represents the horizontal field of view; ppd represents pixels per degree; lp / ° represents line pairs per degree. Converting the image plane's lp / mm to a visual angle scale is closer to the scale of the human eye / scene.

[0088] Time metric: Equivalent exposure time Time resolution Fuzziness refers to the intensity of motion fuzziness. .

[0089] The measured MTF index MTF50 / 10 can represent the spatial resolution achievable in the field, while the measured optical intrinsic MTF index MTF50 / 10 can characterize the optical / assembly limit resolution.

[0090] Archive the "curve + indicator + operating condition":

[0091] First-order uncertainty propagation assessment was used for key indicators: .

[0092] in, This represents the i-th input variable used to calculate the target index y; The standard uncertainty is represented by rpm; λ represents the rotational speed; c represents the illumination center wavelength; and c represents the operating condition vector. , These represent the frequency points where the MTF reaches 0.5 and 0.1, respectively. Indicates equivalent exposure time; Temporal resolution is used to constrain dynamic motion blur and flicker, and to configure strobe / exposure; MBI is motion blur intensity; NTU is turbidity; T represents transmittance; Temp represents temperature; P represents pressure; and E represents illuminance.

[0093] In this embodiment of the invention, a schematic diagram of the structure and fluid circulation of the spinning simulation calibration chamber is provided for reference. Figure 4 It includes a pressure chamber, which contains a rotating drum and a pressure gauge. An external pipe connects to the interior, and the pipe is equipped with a turbidity meter, a heater, a thermometer, and an observation port. A circulation pump is installed on the outer wall of the pressure chamber.

[0094] The working conditions were reproduced in the ground spinning simulation chamber. Consistency with in situ results:

[0095] like This is considered to have passed the consistency calibration.

[0096] in, This indicates the ground spin simulation chamber test. , Indicates downhole drilling field testing , This indicates the ground spin simulation chamber test. , Indicates downhole drilling field test , Indicates the equivalent exposure time.

[0097] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A device for detecting the resolution of drilling-mounted video imaging, characterized in that, include: Internally, it has a transparent pressure-resistant window for a composite target, a coaxial programmable illumination assembly, an IMU, an environmental sensor, an interface module, an imaging assembly, and a control and processing unit; Environmental sensors include: turbidity / transmittance sensors, illuminance sensors, temperature sensors, and pressure sensors; The composite target is a concentric multi-ring composite target. The outer ring is a hypotenuse target, the middle ring is a Siemens star target, and the inner ring is a circular observation and imaging area. There is a ring-shaped isolation area between the middle and outer rings. The XOY pixel axis is constructed with the center of the inner ring as the origin. The outer ring has four hypotenuses, with the two endpoints of the hypotenuses on the outer circle of the outer ring. Perpendicular segments are drawn from the origin to the hypotenuses, satisfying the following conditions: the four perpendicular segments are of equal length, and their directions are clockwise: positive X-axis, negative X-axis, positive Y-axis, and negative Y-axis. Angle; Siemens star sector count is 24~72; Coaxial programmable lighting components are used to provide controllable lighting; The interface module is used for power and data transmission; IMU data, environmental sensor data, images acquired by the imaging components, and composite target images are processed by the control processing unit to obtain the imaging resolution.

2. The method for detecting the resolution of drilling-mounted video imaging according to claim 1, characterized in that, Based on the aforementioned device for detecting the resolution of drill-mounted video imaging, the method includes: S1. Synchronously acquire composite target image data, IMU data and environmental sensor data, and perform time alignment on the data; S2. Calculate and measure the MTF curve based on the composite target image; Reconstructing image plane trajectory and calculating motion MTF based on IMU data; Establish media MTF based on environmental sensor data; Pixel aperture MTF is established based on the images obtained by the imaging components; S3. Separate the motion MTF, medium MTF and pixel aperture MTF from the measured MTF curve to obtain the optical intrinsic MTF; S4. Detect the resolution of the drilling video imaging based on the measured MTF and optical intrinsic MTF.

3. The method for detecting the resolution of drilling-mounted video imaging according to claim 1, characterized in that, The formula for measuring MTF using a Siemens star target is: in, Indicates radial frequency as The MTF was measured at that time. This indicates the radial frequency corresponding to the circumference of a circle with radius r. To measure the polar coordinate radius of the star marker, and These are the inner and outer radii of the central ring where the Siemens star is located. Represents the phase-locked cosine component. The circumference of a circle with radius r is at an angle grayscale at that location M represents the circumferential angle, and M represents the black-and-white logarithm of the Siemens star target. Indicates adjustment system, Represents the phase-locked sinusoidal component. This represents the average brightness on the circumference of a circle with radius r.

4. The method for detecting the resolution of drilling-mounted video imaging according to claim 1, characterized in that, The MTF measured using the SFR hypotenuse method based on the hypotenuse target is given by the following formula: in, Indicates direction The measured MTF, This represents the k-th spatial frequency, where k represents the frequency index. Represents the discrete spectrum. Indicates Fourier transform, This represents the windowed line spread function, where N represents the number of sampling points. Indicates the normal bin step size. This represents the SFR oversampling factor, where p represents the pixel pitch. Represents the window function. Represents the line spread function. This represents the average gray level per box as indicated by the edge spread function. This represents the set of pixel indices contained in the nth bin. Indicates the first i 1 pixel, Indicates the first i One-dimensional coordinates from the center of each pixel to the direction of the hypotenuse normal. Indicates the first i The coordinates of the center of each pixel This represents the signed perpendicular distance from the origin to the hypotenuse.

5. The method for detecting the resolution of drilling-mounted video imaging according to claim 1, characterized in that, The motion MTF is expressed by the formula: in, Indicates frequency as f Motion MTF during time, Indicates the exposure time. i Represents the imaginary unit. This represents the equivalent trajectory of the image plane at time t. This represents the initial image shift, and t represents time. Indicates the image plane in Instantaneous velocity at time.

6. The method for detecting the resolution of drilling-mounted video imaging according to claim 1, characterized in that, The medium MTF is expressed by the formula: in, Indicates frequency as f Medium MTF at that time Indicates the equivalent scattering standard deviation. and The coefficients represent the fit, and NTU represents turbidity. Indicates the effective optical path.

7. The method for detecting the resolution of drilling-mounted video imaging according to claim 1, characterized in that, The pixel aperture MTF is expressed by the formula: in, express Pixel aperture MTF at that location Let p represent the two components of the two-dimensional spatial frequency vector 𝑓 on the x-axis and y-axis, and p represent the pixel size.

8. The method for detecting the resolution of drilling-mounted video imaging according to claim 1, characterized in that, The intrinsic optical MTF is expressed by the formula: in, The frequency after compensation is f The optical intrinsic MTF of time, Indicates frequency as f The MTF was measured at that time. The frequency after compensation is f Medium MTF at that time The frequency after compensation is f Motion MTF during time, Indicates frequency as f The pixel aperture MTF at that time.

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