A Judgment Method of Focus Consistency of Stereo Microscope
The images taken by the microscope at the same depth have different resolutions in different areas. By adjusting the position of the microscope axis, the sequence images of the calibration plate are obtained, and the connected region segmentation method is used to segment the images of the calibration plate at different depths, and the center of the dot is extracted. Then use the focus discrimination function to obtain the clearest position corresponding to each dot area in the sequence image, use the sharpness-depth relationship curve to obtain the depth information, and combine the depth information with the plane information to reconstruct a set of clear focus plane, which is the plane of total focus.
Stereo Microscope Focus Consistency Judgment Principle
In camera imaging, when the object distance u, image distance v, and focal length f satisfy the formula (1), a clear image can be obtained.
The images taken by the microscope at the same depth have different resolutions in different areas. By adjusting the position of the microscope axis, the sequence images of the calibration plate are obtained, and the connected region segmentation method is used to segment the images of the calibration plate at different depths, and the center of the dot is extracted. Then use the focus discrimination function to obtain the clearest position corresponding to each dot area in the sequence image, use the sharpness-depth relationship curve to obtain the depth information, and combine the depth information with the plane information to reconstruct a set of clear focus plane, which is the plane of total focus.
Stereo Microscope Focus Consistency Judgment Principle
In camera imaging, when the object distance u, image distance v, and focal length f satisfy the formula, a clear image can be obtained.
If any parameter changes, the clear image point will become a circular spot, thus forming a blurred image". Assume that the radius of the circular spot is r; the radius of the lens is T0; the distance from the focal plane to the focal plane is Av. By similar triangles Knowledge can be known
According to the principle of stereo microscope imaging, it can be known that the relationship between the binocular imaging plane determines the relationship between the binocular image focus plane. From the formula (4), it can be seen that according to the angle a between the left and right imaging planes and the angle a of the focus plane, there is a qualitative relationship, so the left and right focus planes The included angle is 0. It can be used as an index for judging the focus consistency of a stereo microscope. At the same time, it can be known that adjusting the angle between the left and right focus planes according to the angle between the imaging planes makes the left and right focus planes as consistent as possible.
experiment platform
The experimental platform consists of a stereo microscope, a precision mobile lifting platform and a computer. The stereo microscope is NSZ-800 microscope from NOVEL OPTICS, the left and right camera resolution is 720×576 pixels, the dot calibration plate is used as the measurement sample, the dot diameter is 25gm, and the spacing is lO0~m. The dot calibration plate is placed on a precision electronically controlled vertical lifting platform (CHU0 SEIKI XA07A-R2H), and the minimum moving step is 2 m. The lifting platform is controlled to move equidistantly, with a step length of 2 m, and a picture is taken for each step, and a total of 117 images are collected.
