Method, system and device for confirming focusing position of optical module

The embodiment of the invention provides a method, a system and a device for confirming a focusing position of an optical module. The optical module comprises a lens group and a display screen; the method comprises the following steps: emitting a first light ray to an optical module through a light source module; in the process of adjusting the distance between the lens group and the display screen, receiving the second light through the imaging camera so as to sequentially obtain multiple frames of imaging pictures; wherein the second light is the light which is reflected by the first light received by the optical module through the display screen, passes through the lens group and then is transmitted to the imaging camera; wherein the multiple frames of imaging pictures correspond to different distances between the lens group and the display screen; obtaining a sharpness value corresponding to the target area in each frame of imaging picture, and obtaining a focusing curve graph according to the sharpness v