Video measuring instrument with sensing structure

The utility model discloses an image measuring instrument with a sensing structure that comprises a stander, a base, a worktable, and a moving system, an illuminating system, an image pick-up system, and a software control system that are composed of a portal frame, transmission shaft systems in X, Y, and Z direction, and a slipper block that is connected with the transmission shaft system in Z direction, as well as a sensing structure that is composed of an emission sensor, a receiving sensor, and a transmission device in Z direction; wherein, the transmission device in Z direction is comoposed of a pair of slide bar assemblies in Z direction that is composed of slide bars and slide bushings as well as a linkage device that is connected with a lampshade through the slide bushings; and the emission sensor and receiving sensor are respectively arranged below the slide bushings through connecting boards and are arranged opposed to each other. The technical proposal of the utility model adopts a regional sensing structure with a small area to conduct rigid location on the highest point of a workpiece and finish the focusing work automatically and have an automatic safe protection effect at the same time, thereby, the likely impact between the camera as well as the upper light source and the workpiece to be measured when being moved downward is avoided; meanwhile, the focusing time is shortened.