Step 2: Adjust the optical path between the laser tube spot and the first reflector.
Put the dimming paper in front of the first lens, and gently press the "click" key by hand (as long as you press and release it immediately, you can see the light spot made by the laser on the dimming paper) to see if the light spot falls on the first lens (preferably in the middle). If they can hit the camera, this step is completed. If the lens is not hit or eccentric, it is necessary to adjust the position or height of the first lens holder (or laser tube) to meet the above standards.
Step 3: Adjust the optical path between the first mirror and the second mirror.