The invention relates to the technical field of optical lens calibration and testing, in particular to a continuous
zoom lens
focal length automatic calibration device which comprises a bearing plate, a fixing plate arranged on the surface of the bearing plate and an
image sensor fixedly arranged on the surface of the fixing plate. A
focal length target adjusting mechanism and a target regulation and control mechanism are arranged on the upper surface of the bearing plate; through cooperation of a plurality of components in the
focal length target adjusting mechanism, when the lens continuously zooms, the driving motor is started, so that the driving shaft drives the connecting rod and the lens
assembly to move, meanwhile, through meshing of the driving gear, the
threaded rod drives the target unit to synchronously move, and therefore the lens
assembly and the target unit synchronously move; the long-focus lens is matched with a farther
object distance, the short-focus lens is matched with a closer
object distance, and based on the trigger switch, when the connecting rod is in contact with the trigger switch, the lens
assembly is started to
shoot, the shot image is displayed on the
image sensor, and the focal length is automatically calibrated.