Image auto-focusing device

Abstract

The invention relates to an automatic image focusing device. The prior automatic focusing device is complex in structure, high in requirements on processing and assembling precision. In the invention,a stator coil is fixedly inlayed in a stator coil mounting groove of the inner sidewall of a shell; a front sleeve-shaped end cover and a back sleeve-shaped end cover are fixed with two end faces ofthe shell; through holes inside the front end cover and the back end cover form an imaging channel; the sleeve parts of the front end cover and the back end cover stretch into the shell; a part of a sleeve rotor is in threaded connection with the front end cover, and the other part of the sleeve rotor is in threaded connection with the back end cover; a focusing lens is fixed inside the sleeve rotor; the tail parts of the front end cover and the back end cover are arranged separately and have an intermediary space as a motion space for the focusing lens. After the focusing device is electrified,a stator generates a rotating magnetic field, and the sleeve rotor can rotate in forward and reverse directions to drive the focusing lens to move left and right, so as to adjust the focal length ofthe lens. The focusing device is simple in structure and reduces the requirements on the processing and assembling precision for all links of the focusing device, thereby reducing the cost of the device.

Description

technical field [0001] The invention belongs to the field of optical-mechanical-electrical integration, and in particular relates to an image automatic focusing device based on digital technology. Background technique [0002] The focusing method of changing the focal length is to change the focal length of the lens by moving the axial position of a lens or a group of lenses in the lens, so that the image distance can be kept constant when the object distance changes. It is one of the most commonly employed focusing methods. The focusing process of this focusing method can be completed manually or automatically by controlling the motor to drive the lens. [0003] The existing autofocus device is composed of a lens assembly, a motor, a driving mechanism, a detection sensor, etc. The motion transmission between the motor and the lens assembly is realized through an external driving mechanism, and the driving mechanism is generally a rack and pinion pair, a rotating screw pair...

AI Technical Summary

Problems solved by technology

The discrete structure of the detection sensor, motor, lens assembly and drive mechanism will complicate the structure of the system, increase the cost, and at the same time increase the processing and assembly accuracy requirements of each link of the focusing device

Due to the addition of the detection sensor, an intermediate detection and data processing process is formed, which inevitably introduces errors and affects the focusing accuracy of the system

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