PRECISION DETECTOR FOR SURVEYOR'S ROD GRATING

The utility model relates to an accuracy detector for surveyor's rod grating belonging to the technical field of the grating digital display. The utility model is characterized in that two rod gratings with the same grating pitch are formed into a pair face to face. The two rod gratings move towards an X direction and a Y direction through a photodetector, measure the light-intensity variation of the moire fringe image, output data via a digital indicator, and obtain the marking line error of each rod grating via the data processing. The utility model has the advantages of high precision, high measuring accuracy free from the limit of the measured rod grating accuracy, good repetitiveness, low cost, strong practicability, convenient operation and use, etc.