A linear optical axis is the center line of a lens or convex lens, along which light propagates when passing through the lens. In optical imaging, the core functions of a linear optical axis include:
1. Determining the imaging position (the perpendicular line connecting the object and the image), ensuring precise image positioning;
2. Controlling the image shape (the image is symmetrical when the object is on the optical axis, and asymmetrical when it deviates), affecting image quality;
3. Calibrating the lens position (it must be aligned with the optical axis and the lens center during manufacturing), ensuring optical performance (e.g., focal length accuracy ±0.1mm). Related applications include optical instrument calibration and laser equipment debugging.