What separates a laser rangefinder from an ultrasonic rangefinder?
During the use of the rangefinder, the relationship between the three axes of the rangefinder (telescope sighting axis, rangefinder emission axis and receiving axis) often changes due to long-term work and vibrations and collisions during transportation. Conventional calibration methods are simple to operate, but the calibration results are not accurate enough.
1. Calibration principle
By measuring the angular value of the range finder in the horizontal direction and the vertical direction of the light return signal range, the correct readings of the dial at the four critical states (weakest return light signal) positions when the three-circle relationship of the range finder meets the requirements are calculated. After rotating the micro-movement screw to the correct reading position of the dial, correct the return light signal of the rangefinder to a critical state, so that the corrected aiming mirror mark is in the center of the return light signal range.
2. Test of parallelism in horizontal direction
(1) Place the reflector at about 200m from the range finder, use the telescope to aim at the mark of the reflector, and read the reading A (145°04'30'') of the horizontal dial.
(2) Slowly rotate the theodolite horizontal micro-movement screw to make the aiming direction deviate from the reflector mark to the left, and observe the change of the return light signal of the range finder until the return light signal is in a critical state (the return light signal is between one grid and no signal When jumping and changing), read level reading A (144°57'59'').
(3) Use the same method to measure the reading A (145°07'37'') of the horizontal dial when it deviates from the critical state on the right side of the reflector mark.
(4) Calculate the horizontal deviation angle according to the following formula:
3. Parallelism correction in the horizontal direction
(1) Calculate the correct angle value when deviating from the critical state on the left and right of the mirror mark according to the following formula.
