Voice coil motor driving method for achieving quick focusing

Abstract

The invention relates to a voice coil motor driving method for achieving quick focusing. The method comprises the steps that the target driving current of a voice coil motor is determined by analyzing focusing signals; the value of the target driving current / 2N is calculated until the value of the target driving current / 2N is equal to the smallest driving current, (N=1, 2, 3, ...); the driving currents are added to the target driving current with the target driving current / 2N as the rising stepping value of the driving currents in N steps, and if the value of the target driving current / 2N has a remainder, the remainder is abandoned, and the remainder is supplemented in the last step. The voice coil motor driving method for achieving the quick focusing can increase the driving currents to a target value fast, the rising control time of the driving currents of the voice coil motor is greatly shortened, large mechanical resonance displacement cannot be caused after target displacement is achieved in a driving mode, the method is an ideal choice of voice coil motor driving control, and the method is easy and convenient to use, has better superiority, and has a wider application range.

Description

technical field [0001] The present invention relates to the technical field of voice coil motors, in particular to the technical field of driving voice coil motors, in particular to a voice coil motor driving method for realizing fast focusing. Background technique [0002] With the improvement of people's living standards, the electronic technology is getting more and more advanced. People have also put forward higher requirements for the performance of camera devices, such as the speed and clarity of taking pictures with mobile phones. In order to achieve clearer and faster pictures, it is necessary to shorten the focusing time of the drive motor. At present, the most common focusing driver used in mobile phones is VCM (Voice Coil Motor). The working principle of VCM is to give a driving current to a coil placed in a magnetic field space. After the specified position is stabilized, the focus is completed and the photo can be taken. The criterion for judging the focus st...

AI Technical Summary

Problems solved by technology

The biggest disadvantage of the direct drive method is that the VCM will have serious mechanical resonance, which will cause the motor to stabilize for a long time, failing to achieve the purpose of faster focusing speed and clearer pictures; although the linear drive method can better solve the problems encountered by the direct drive method. The mechanical resonance problem, but its own drive control time is longer, so it can't achieve the purpose of faster focusing speed and clearer pictures; the dual-level drive mode is a compromise between direct drive mode and linear drive mode method, can not achieve the desired effect

Therefore, a new technology is urgently needed for VCM drive. This technology must solve two problems: 1. The control time for the motor drive current to rise should be short; 2. There should be no large mechanical resonance after the drive reaches the target displacement

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