Automatic focusing device for projective bulb based on light spot detection and use method thereof

Abstract

The invention discloses an automatic focusing device for a projective bulb based on light spot detection and a use method thereof. The automatic focusing device comprises a lamp cup, a lamp cup clamping table, a screw I, a lampwick, a lampwick clamping frame, a large guide rail, a large slider, a screw II, an optical planar lens, a clamping holder, a convex lens, a supporting column, an optical filter, a two-dimensional photoelectric position sensor (PSD), a signal processing system, a PLC (programmable logic controller), a servo motor and a three-dimensional precise adjusting table, wherein light emitted from the lampwick can be reflected by the inner surface of the lamp cup to form parallel light beams, the parallel light beams can be transmitted and reflected twice by the optical planar lens, small parts of the light can be reflected to the convex lens, and then the light irradiates on the PSD by the optical filter after being gathered; a signal output by the PSD can be subjected to a series of conversion by the signal processing system, the PLC, the servo motor and the three-dimensional precise adjusting table; and finally the signal is used to control the position of the lampwick in the lamp cup. The device provided by the invention has the advantages of simple use method, low cost, high efficiency, high focusing precision and the like.

Description

technical field [0001] The invention relates to the field of projectors, in particular to an automatic focusing device for projection bulbs based on spot detection and a method for using the same. Background technique [0002] The projector bulb is one of the important components of the projector and one of the most important consumables of the projector, which is closely related to the overall picture performance of the projector. The quality of the projection bulb basically depends on the quality of the lamp cup, the quality of the wick and the quality of the assembly process. It is a technical difficulty to control the position of the wick in the lamp cup, that is, to adjust the focus, so as to obtain the desired light source. The so-called "a slight difference is a thousand miles away", a slight deviation in the position of the wick will cause the light intensity, parallelism and uniformity of the light beam emitted by the light source to be affected, thereby greatly af...

AI Technical Summary

Problems solved by technology

[0004] Some enterprises manually judge the size and center position of the emitted light spot, so as to manually adjust the position of the wick, and then perform subsequent glue injection and other processes; this method has many problems, such as low efficiency and low focusing accuracy.

[0005] Patent application number CN200810084310.0 proposes a method of obtaining control parameters by using a vision system and an image processing system. Although it is feasible, it is expensive and complicated

[0006] The Japanese patent with the application number JP200623564 adopts a method of placing 9 sensors in the central part of 9 rectangular areas in which the X and Y directions of the illuminated surface are equally divided into 2 root squares for testing. Although it is feasible, it is accurate. degree still needs to be improved

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