Before a camera product is formed, the lens module will be customized from the lens module manufacturer. The lens module manufacturer will often ask you about the requirements for lens parameters. When customizing the lens module, in addition to the clarity index, the angle and focal length of the lens module are also key parameters. When purchasing, it is necessary to select a lens with a suitable focal length, angle and depth of field from the lens module manufacturer according to the actual usage scenario.

- What are the parameters of the lens module?
1. Focal length: refers to the distance from the optical center of the lens to the focus of light gathering when parallel light is incident. The length of the focal length of the lens determines the size of the image taken, the size of the angle of view, the size of the depth of field and the perspective strength of the picture.
2. Field of view angle: the angle formed by the lens as the vertex and the two edges of the maximum range where the object image of the tested target can pass through the lens.
3. Depth of field: refers to the range of the distance before and after the subject measured by the imaging of the lens module that can obtain a clear image.

2. How to adjust the focus of the lens module?
1. Open and short circuit and electrical test to detect the electrical continuity performance of the lens module.
2. In the black field test, the hood is moved downward and the cover is set on the lens module to form a black field environment; once image recognition and height measurement, the position of the lens is recognized, and the distance between the lens and the detection surface of the laser rangefinder is measured.
3. Focusing, the focusing instrument is inserted into the lens module and drives the lens module to rotate relative to the sound and vibration motor to adjust the distance of the lens relative to the chart; secondary image recognition and height measurement, identify the position of the camera, and measure the relative distance of the lens The laser rangefinder detects the distance of the face.
4. In the white field test, the white field light source is horizontally close to and illuminates the lens module to form a white field environment.
5. Dispensing, the dispensing head can be close to or inserted into the gap between the lens module and the sound vibration motor for dispensing operation.
5. Curing, the curing light source illuminates the glue point on the lens module for curing operation.
6. In the activation step, the activation component controls the opening and closing of the lens module, and the lens module can perform at least one photo-taking operation to obtain photo information.

3. What is the effect of different focal lengths?
1. The smaller the focal length, the closer the visual distance and the larger the field of view.
2. The larger the focal length, the farther the visual distance and the smaller the field of view.