1. The imaging size of the lens shall be consistent with the size of the CCD target surface of the industrial endoscope camera. As mentioned above, it has specifications of 1 inch, 2 / 3 inch, 1 / 2 inch, 1 / 3 inch, 1 / 4 inch, 1 / 5 inch, etc.
2. The resolution of the lens is the internal index describing the imaging quality of the lens, which is the optical transfer function and distortion of the lens. However, for supporters, what needs to be understood is only the spatial resolution of the lens. Taking the number of black-and-white stripes that can be distinguished per millimeter as the measurement unit, the calculation formula is: lens resolution n = 180 / height of frame format. As the size of CCD target surface of industrial endoscope camera has been standardized, such as 1 / 2-inch camera, its target surface is 6.4mm wide * 4.8mm high, and 1 / 3-inch camera is 4.8mm wide * 3.6mm high. Therefore, for 1 / 2 inch format CCD target, the low resolution of the lens should be 38 pairs of lines / mm. For 1 / 3 inch format camera, the resolution of the lens should be greater than 50 pairs of lines. The smaller the target surface of the camera, the higher the resolution of the lens.
3. Lens focal length and field of view angle firstly, the focal length of the lens is selected according to the distance from the industrial endoscope camera to the monitored target. After the lens focal length f is determined, the field of view is determined by the target surface of the camera.
4. Aperture or luminous flux the luminous flux of a lens is measured by the ratio of the focal length of the lens to the luminous aperture, marked with F. each lens is marked with its large F value. The luminous flux is inversely proportional to the square of the F value. The smaller the F value, the larger the aperture. Therefore, manual aperture or automatic aperture lens should be selected according to the light change degree of the monitored part.