Laser divergence angle measuring device and measuring method based on full-automatic hole alignment method

The invention provides a laser divergence angle measuring device based on the full-automatic hole alignment method, which comprises a computing control unit, a stepping motor controller and a laser. A long-focus length, a hole diaphragm array, a reflector and a CCD (charge coupled device) are sequentially arranged in the horizontal advancing direction of a laser beam generated from the laser, wherein the hole diaphragm array is provided with a plurality of light transmitting holes and located on the focus of the long-focus lens, the reflector and the laser beam form the included angle of 45 degrees, an energy meter is arranged on a vertical light path of the light beam after the light beam is reflected by the reflector, a two-dimensional electric control translation platform is connected to the hole diaphragm array, a one-dimensional electric control translation platform is connected to the reflector, and the computing control unit is connected with the stepping motor controller, the CCD and the energy meter respectively. The two-dimensional translation platform is controlled to move by control signals so that the center of each light transmitting hole is coincided with the center of each laser light spot. High precision in alignment is achieved and the laser divergence angle computed by the device is more accurate.