A laser calibration measurement method and device for the planar projection area of a fine object

Abstract

The application discloses a kind of laser calibration measurement method and device of fine object plane projection area, which comprises the following steps: (1) the measuring object is placed on the stage of microscope;(2) start laser emitter, form the initial spot t1 of size not adjusted;(3) adjust laser emitter, obtain the adjusted spot t2;(4) through camera, obtain the microscopic image with spot t2 and measuring object through microscope;(5) according to the parameter of laser emitter, the size of adjusted spot t2 is calculated, the pixel point quantity of spot t2 in image is counted, and the mapping relationship ratio r of the size of spot t2 and the pixel point quantity of spot t2 is obtained;(6) the pixel point quantity of measuring object in image is counted, and the actual area of measuring object is calculated in combination with mapping relationship ratio r.The laser calibration measurement method introduces laser spot as reference, and the area of spot reflects the area of fine object, which is conducive to improving the accuracy of measurement.

Description

Technical Field

[0001] This invention relates to laser measurement methods and apparatus, specifically to a laser calibration measurement method and apparatus for the planar projected area of ​​a fine object. Background Technology

[0002] Microscopes are used to study minute objects, magnifying them to observe their various features. In microbiology, obtaining the area of ​​the object is often necessary. This can be achieved by using a camera to capture images of microorganisms through a microscope, processing the images, and calculating pixel size to represent the projected area of ​​the object.

[0003] The above measurement methods, lacking real-world references and relying entirely on virtual analysis and calculations, yield inaccurate results. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned problems and provide a laser calibration measurement method for the planar projected area of ​​a fine object. This laser calibration measurement method introduces a laser spot as a reference, and the area of ​​the spot reflects the area of ​​the fine object, which helps to improve the accuracy of the measurement.

[0005] Another object of the present invention is to provide a laser calibration and measurement device for the planar projected area of ​​a fine object.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A laser calibration measurement method for the planar projected area of ​​a fine object includes the following steps:

[0008] (1) Place the object to be measured on the microscope stage and ensure that the object to be measured is within the field of view of the microscope;

[0009] (2) Start the laser emitter to form an initial spot t1 that has not been adjusted in size, and ensure that the initial spot t1 is within the field of view of the microscope;

[0010] (3) Adjust the laser emitter to obtain the adjusted spot t2;

[0011] (4) Obtain a microscopic image of the object being measured by passing a camera through a microscope, showing the light spot t2;

[0012] (5) Calculate the size of the adjusted spot t2 based on the parameters of the laser emitter, count the number of pixels of spot t2 in the image, and obtain the mapping relationship r between the size of spot t2 and the number of pixels of spot t2.

[0013] (6) Count the number of pixels of the object in the image, and then calculate the actual area of ​​the object by combining the mapping ratio r.

[0014] In a preferred embodiment of the present invention, in step (5), the formula for calculating the area of ​​the adjusted light spot t2 is:

[0015]

[0016] In the formula, ω t2 ω is the diameter of the laser spot, and ω1 is the adjusted size of the laser waist aperture, obtained by adjusting ω0; where wavelength λ and beam quality M are... 2 The working distance z and the waist beam diameter ω0 are both known quantities.

[0017] Furthermore, the actual area S of the light spot t2 t3 for:

[0018]

[0019] In the formula, S t3 To correct for the area of ​​the elliptical spot t3, θ is the angle between the laser beam and the plane.

[0020] In the above formula, to correct the size and shape of the light spot t2, the effect of the incident angle of the light ray on the light spot needs to be considered. Assuming the angle between the light ray and the plane is θ, then the projected length of the diameter of the light spot t2 on the plane becomes:

[0021] ω t2，proj =ω t2 ·cos(θ);

[0022] When light rays strike a plane at a certain angle, the size and shape of the light spot t2 will be affected. The size of the light spot will change due to the angle, changing from a circle to an ellipse. The size (diameter) of the light spot t2 needs to be multiplied by cos(θ) to obtain the projection length on the plane.

[0023] The shape of the light spot t2 will change from a circle to an ellipse. Let the light spot that becomes an ellipse be t3. Then the length of the major axis of t3 is ω. t2 cos(θ), with minor axis length ω t2 .

[0024] In a preferred embodiment of the present invention, in step (6), the formula for calculating the actual area of ​​the object being measured is:

[0025] real_object = pix_object *r;

[0026] In the formula, real_object is the actual area of ​​the object being measured, and pix_object is the number of pixels in the object being measured.

[0027] In a preferred embodiment of the present invention, the calculation results are corrected by an infrared photosensitive ranging mechanism, wherein the infrared photosensitive ranging mechanism is provided in at least two sets and each set of the infrared photosensitive ranging mechanism includes an infrared photosensitive rangefinder and a ranging adjustment motor.

[0028] During distance measurement, the infrared photoelectric rangefinders corresponding to each group are driven by the distance adjustment motors of each group to adjust their attitude so that the measurement point of the infrared photoelectric rangefinder coincides with the measurement object, and the distance measurement result value is returned: d1cos(θ1), d2cos(θ2)...dncos(θn);

[0029] The measurement results of each infrared photosensitive ranging mechanism are calculated using the error propagation formula, with d1cos(θ1)=δd1, d2cos(θ2)=δd2……dncos(θn)=δdn;

[0030] Then we have:

[0031]

[0032] The learning results determine σ_accept. When the total error σtotal is less than or equal to σaCCept, the distance measurement result is output; otherwise, the above measurement steps are repeated.

[0033] Furthermore, the corrected calculation results are as follows:

[0034]

[0035] In the formula, Final_Result is the final measurement result, pix_object is the pixel size of the object being measured, λ is the wavelength, and M... 2 Let f be the beam quality, f be the focal length, Loss(y) be the weights obtained from the training set, and σi be the standard deviation of the i-th measurement.

[0036] A laser calibration and measurement device for the planar projected area of ​​a fine object includes a microscope, a camera, and a laser emitter;

[0037] The camera is positioned above the eyepiece of the microscope;

[0038] The microscope has an adjustable mounting bracket below the objective lens, which can be vertically and movably mounted on the microscope.

[0039] The laser emitter is mounted on an adjustable mounting bracket.

[0040] In a preferred embodiment of the present invention, the laser emitter includes a laser source for emitting laser light, a focal length adjustment component for adjusting the focal length of the light spot, a variable aperture for adjusting the light transmittance of the light spot, and a reflection component for adjusting the position and angle of the light spot. The reflection component includes a reflector and an emission adjustment motor.

[0041] In a preferred embodiment of the present invention, an infrared photosensitive ranging mechanism for correcting the calculation results is further included. The infrared photosensitive ranging mechanism is provided in at least two sets and arranged along the circumferential direction on an adjustable mounting frame. Each set of infrared photosensitive ranging mechanisms includes an infrared photosensitive rangefinder and a ranging adjustment motor.

[0042] Compared with the prior art, the present invention has the following advantages:

[0043] 1. The laser calibration measurement method of the present invention introduces a laser spot as a reference and calculates the area of ​​a fine object from the actual area of ​​the spot, which helps to improve the accuracy of the measurement.

[0044] 2. By integrating the microscope, camera, and laser emitter together, it is easier to operate under the microscope, improving the convenience and efficiency of experiments. Attached Figure Description

[0045] Figure 1 This is a front view of the laser calibration and measurement device for the planar projected area of ​​minute objects according to the present invention.

[0046] Figure 2 This is a three-dimensional structural schematic diagram of the laser calibration and measurement device for the planar projected area of ​​minute objects according to the present invention. Detailed Implementation

[0047] To enable those skilled in the art to fully understand the technical solutions of the present invention, the present invention will be further described below in conjunction with embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0048] See Figure 1-2 The laser calibration and measurement device for the planar projected area of ​​a fine object in this embodiment includes a microscope 1, a camera 2, and a laser emitter 3; the camera 2 is disposed above the eyepiece of the microscope 1; an adjustable mounting bracket 4 is provided below the objective lens of the microscope 1, and the adjustable mounting bracket 4 can be vertically and movably disposed on the microscope 1; the laser emitter 3 is disposed on the adjustable mounting bracket 4.

[0049] Specifically, the laser emitter 3 includes a laser source for emitting laser light, a focal length adjustment component for adjusting the focal length of the light spot, a variable aperture for adjusting the light transmittance of the light spot, and a reflection component for adjusting the position and angle of the light spot. The reflection component includes a reflector and an emission adjustment motor.

[0050] See Figure 1-2 The laser calibration and measurement device also includes an infrared photosensitive ranging mechanism 5 for correcting the calculation results. The infrared photosensitive ranging mechanism 5 has at least two sets and is arranged along the circumferential direction on the adjustable mounting frame 4. Each set of infrared photosensitive ranging mechanism 5 includes an infrared photosensitive rangefinder and a ranging adjustment motor.

[0051] See Figure 1-2 The laser calibration measurement method for the planar projected area of ​​a fine object in this embodiment includes the following steps:

[0052] (1) Place the object to be measured (e.g., a two-leaved spider mite) on the stage of microscope 1, ensuring that the object to be measured is within the field of view of microscope 1.

[0053] (2) Start the laser emitter 3 to form an initial light spot t1 that has not been adjusted in size, and ensure that the initial light spot t1 is within the field of view of the microscope 1.

[0054] (3) Adjust the laser emitter 3 to obtain the adjusted spot t2.

[0055] (4) A microscopic image of the object being measured is obtained through the microscope 1 with the light spot t2 via the camera 2.

[0056] (5) Calculate the size of the adjusted spot t2 based on the parameters of the laser emitter 3, count the number of pixels of spot t2 in the image, and obtain the mapping relationship r between the size of spot t2 and the number of pixels of spot t2.

[0057] (6) Count the number of pixels of the object in the image, and then calculate the actual area of ​​the object by combining the mapping ratio r.

[0058] Furthermore, in step (5), the formula for calculating the area of ​​the adjusted spot t2 is:

[0059]

[0060] In the formula, ω t2 ω is the diameter of the laser spot, and ω1 is the adjusted size of the laser waist aperture, obtained by adjusting ω0; where wavelength λ and beam quality M are... 2 The working distance z and the waist beam diameter ω0 are both known quantities.

[0061] Furthermore, the actual area S of the light spot t2 t3 for:

[0062]

[0063] In the formula, S t3To correct for the area of ​​the elliptical spot t3, θ is the angle between the laser beam and the plane.

[0064] In the above formula, to correct the size and shape of the light spot t2, the effect of the incident angle of the light ray on the light spot needs to be considered. Assuming the angle between the light ray and the plane is θ, then the projected length of the diameter of the light spot t2 on the plane becomes:

[0065] ω t2，proj =ω t2 ·cos(θ);

[0066] When light rays strike a plane at a certain angle, the size and shape of the light spot t2 will be affected. The size of the light spot will change due to the angle, changing from a circle to an ellipse. The size (diameter) of the light spot t2 needs to be multiplied by cos(θ) to obtain the projection length on the plane.

[0067] The shape of the light spot t2 will change from a circle to an ellipse. Let the light spot that becomes an ellipse be t3. Then the length of the major axis of t3 is ω. t2 cos(θ), with minor axis length ω t2 .

[0068] Furthermore, in step (6), the formula for calculating the actual area of ​​the measured object is:

[0069] real_object = pix_object *r;

[0070] In the formula, real_object is the actual area of ​​the object being measured, and pix_object is the number of pixels in the object being measured.

[0071] Furthermore, the calculation results are corrected by the infrared photosensitive ranging mechanism 5. During ranging, the corresponding infrared photosensitive ranging instruments are driven by the ranging adjustment motors of each group to adjust their attitude so that the measuring point of the infrared photosensitive ranging instrument coincides with the measuring object, and the ranging result value is returned: dlcos(θ1), d2cos(θ2)...dncos(θn).

[0072] The measurement results of each infrared photosensitive ranging mechanism 5 are calculated using the error propagation formula, with dlcos(γ1)=δd1, d2cos(γ2)=δd2……dncos(θn)=δdn;

[0073] Then we have:

[0074]

[0075] The learning results determine σ_accept. When the total error σtotal is less than or equal to σaccept, the distance measurement result is output; otherwise, the above measurement steps are repeated.

[0076] Furthermore, the corrected calculation results are as follows:

[0077]

[0078] In the formula, Final_Result is the final measurement result, pix_object is the pixel size of the target object, λ is the wavelength, and M... 2 Let f be the beam quality, f be the focal length, Loss(y) be the weights obtained from the training set, and σi be the standard deviation of the i-th measurement.

[0079] Furthermore, σ_aCCept is obtained through the following method:

[0080] Data Collection: Using calibrated (actually measured) grids or patterns, acquire multiple image samples through this system. These images should contain minute objects and their corresponding grids or patterns of known actual size.

[0081] The system extracts size and pixel count using its method: it extracts features of minute objects from each image and marks pixels corresponding to grids or patterns of known size.

[0082] Establish an error model: For each image, calculate the difference between the actual measured value and the known calibration value of the minute objects in the image. This will give the error σ for each measurement.

[0083] Statistical analysis: Perform statistical analysis on the errors of all images, calculating the mean, variance, and standard deviation of the errors. These statistics will help determine the distribution characteristics of the errors.

[0084] Determine the error threshold: Based on the error distribution, determine a reasonable error threshold σ_accept. This threshold can be determined empirically, for example, by choosing a certain percentile of the error distribution (such as 95%) as the threshold.

[0085] Machine learning model training: Using extracted features and corresponding error data, a machine learning model is trained that can predict errors in subtle objects in a new image.

[0086] Model validation and error threshold tuning: Use a validation set to evaluate the performance of the machine learning model and tune σ_accept to ensure the accuracy and reliability of the model's predictions.

[0087] Continuous iteration: As new data is continuously added, the model is continuously optimized and the σ_accept value is updated to adapt to new data characteristics and measurement conditions.

[0088] The above are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above content. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A laser calibration measurement method for the planar projected area of ​​a fine object, characterized in that, Includes the following steps: (1) Place the object to be measured on the microscope stage and ensure that the object to be measured is within the field of view of the microscope; (2) Start the laser emitter to form an initial spot t1 that has not been adjusted in size, and ensure that the initial spot t1 is within the field of view of the microscope; (3) Adjust the laser emitter to obtain the adjusted spot t2; (4) Obtain a microscopic image of the object being measured by passing a camera through a microscope, showing the light spot t2; (5) Calculate the size of the adjusted spot t2 based on the parameters of the laser emitter, count the number of pixels of spot t2 in the image, and obtain the mapping relationship r between the size of spot t2 and the number of pixels of spot t2; (6) Count the number of pixels of the object being measured in the image, and then calculate the actual area of ​​the object being measured by combining the mapping ratio r; The calculation results are corrected by an infrared photosensitive ranging mechanism. The infrared photosensitive ranging mechanism is provided in at least two sets, and each set of infrared photosensitive ranging mechanism includes an infrared photosensitive rangefinder and a ranging adjustment motor. During distance measurement, the infrared rangefinders of each group are driven by the distance adjustment motors to adjust their attitude so that the measurement point of the infrared rangefinder coincides with the measurement object, and the distance measurement result value is returned: d1cos(θ1), d2cos(θ2)...dncos(θn); The measurement results of each infrared photosensitive ranging mechanism are calculated using the error propagation formula, with d1cos(θ1)=δd1, d2cos(θ2)=δd2……dncos(θn)=δdn; Then we have: ； σ_accept is determined based on the learning results. When the total error σtotal is less than or equal to σaccept, the ranging result is output; otherwise, the above measurement steps are repeated. The corrected calculation results are as follows: ； In the formula, Final_Result is the final measurement result, pix_object is the pixel size of the measured object, λ is the wavelength, and Loss(y) is the weight obtained from the training set. Let be the standard deviation of the i-th measurement; In step (5), the formula for calculating the area of ​​the adjusted spot t2 is: ； In the formula, ω t2 λ is the diameter of the laser spot, and ω1 is the size of the adjusted laser waist beam aperture, which is obtained by adjusting ω0; where wavelength λ, working distance z, and waist beam aperture ω0 are all known quantities. The actual area of ​​the light spot t2 for: ； In the formula, Let θ be the area of ​​the laser spot t2 corrected to an elliptical laser spot t3, and θ be the angle between the laser beam and the plane. In step (6), the formula for calculating the actual area of ​​the object being measured is: real_object = pix_object *r; In the formula, real_object is the actual area of ​​the object being measured, and pix_object is the number of pixels in the object being measured.

2. A laser calibration and measurement device for applying the laser calibration and measurement method for the planar projected area of ​​a fine object as described in claim 1, characterized in that, Includes microscopes, cameras, and laser emitters; The camera is positioned above the eyepiece of the microscope; The microscope has an adjustable mounting bracket below the objective lens, which can be vertically and movably mounted on the microscope. The laser emitter is mounted on an adjustable mounting bracket.

3. The laser calibration and measurement device according to claim 2, characterized in that, The laser emitter includes a laser source for emitting laser light, a focal length adjustment component for adjusting the focal length of the light spot, a variable aperture for adjusting the light transmittance of the light spot, and a reflection component for adjusting the position and angle of the light spot. The reflection component includes a reflector and an emission adjustment motor.

4. The laser calibration and measuring device according to claim 2, characterized in that, It also includes an infrared photosensitive ranging mechanism for correcting the calculation results. The infrared photosensitive ranging mechanism has at least two sets arranged along the circumference on an adjustable mounting frame. Each set of infrared photosensitive ranging mechanisms includes an infrared photosensitive rangefinder and a ranging adjustment motor.

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