The invention belongs to the field of detection, and relates to improvement of a projection enlarged image detection method. An efficient projection enlarged image detection method can be used for detecting a projection enlarged image, quick measuring of the projection enlarged image is achieved, a visualization detection data processing mode is formed, efficiency, the automation degree and the intelligence degree of a detection device are improved, complexity and mistakes during measuring and calculation processes in the prior art are reduced, data accuracy is improved, detection efficiency and detection accuracy are improved, and the first-class level of the industry is reached.