What you are using now Intelligent mobile phone Mobile terminals are often encountered in mobile electronic devices such as tablets camera Focus speed and quality. In motor testing and evaluation, the motor linearity is an important indicator. Whether the motor linearity is good or not is directly related to the focusing speed and quality of mobile equipment. When the motor linearity is poor, it is easy to cause out of focus or focusing No, the image is blurry. The main reasons for poor motor linearity are as follows:
1. Poor motor body: the linearity of motor movement curve is poor, and the curve is too high or too low.
2. Assembly process problem: the load of glue and lens exceeds the load of the motor itself, resulting in insufficient driving force and low curve when the motor moves; If the glue penetrates or too much sticks to the motor, the motor will not be able to push and focus.
3. Other reasons: for example, excessive torque may cause damage to the motor.
When the module leaves the factory, it must ensure that the motor is in normal working condition. First, reduce the factors that cause the motor defects by controlling the process flow, and then prevent the defective module from being shipped to the client through some anti flow measures. Testing the motor curve through the laser tester is a way to test the linearity of the motor:
The following figure is a normal motor curve. The abscissa in the figure is the current value, the ordinate is the motor stroke, the blue curve is the curve when the motor moves forward from the origin, and the green straight line is a straight line drawn through the position of two points. The higher the coincidence between the blue curve and the green straight line, the better the linearity of the motor. From this curve, we can also calculate the starting current of the motor, the maximum travel range, motor hysteresis and other data. The consistency of linearity can be judged by testing multiple motor curves.
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