In order to meet the detection requirements of the orientation of the incoming laser beam in the laser alarm scenario, a surface mask coding laser angle detection component based on Gray code was designed. A new coding mode of 10 bit coding was adopted, in which 7 bits, 1 bits and 2 bits were used as angle coding, positive and negative coding and reference bits respectively. A new 2-D surface mask plate was designed. The detection field of view angle was ±30°, the resolution was 1°, and the appropriate irradiation intensity threshold was selected to accurately distinguish the code “0” and “1”. Through simulation software, the optical trace and irradiation intensity of the detector target surface under different angles of view were obtained, and the irradiation intensity values were normalized. The results show that the coding results identified by the light trace are basically consistent with the designed coding table. Using 47.5% of the average irradiation intensity of the reference bit sensor 10^# as the threshold, the code “0” and “1” can be accurately distinguished. The detection component enables a more uniform beam intensity distribution, avoiding the edge effects and inhomogeneity that can occur with traditional flat masks. The design of high resolution angle detection module based on Gray code is feasible, and the research provides a reference for detection signal processing in laser alarm applications.