Driving calibration apparatus of electrostatic MEMS scanning mirror and driving calibration method thereof
View Patent ↗The invention provides a driving calibration apparatus of an electrostatic MEMS scanning mirror and a driving calibration method thereof The driving calibration method includes the following steps. Different reference voltages are sequentially set to drive a plane mirror of the electrostatic MEMS scanning mirror to swing. Projection positions on a projected surface corresponding to the reference voltages that the laser beam projects to are determined. A driving lookup table is established according to the reference voltages and the corresponding projection positions. Calibrated driving voltages corresponding to ideal projection positions are determined according to the driving lookup table. The pane mirror is driven to swing according to the calibrated driving voltages.
1. A driving calibration apparatus of an electrostatic MEMS scanning mirror comprising a plane mirror serving to guide a laser beam to project on a projected surface, the driving calibration apparatus comprising:
a voltage setting unit, serving to set a plurality of different reference voltages to drive the plane mirror to swing;
a image capture unit, serving to sense a plurality of projection positions on the projected surface corresponding to the plurality of reference voltages that the laser beam projects to; and
a data processing unit, serving to establish a driving lookup table according to the reference voltages and the corresponding projection positions and determine calibrated driving voltages corresponding to a plurality of ideal projection positions according to the driving lookup table, wherein the voltage setting unit drives the plane mirror to swing according to the calibrated driving voltages.
2. The driving calibration apparatus of the electrostatic MEMS scanning mirror according to claim 1 , wherein the reference voltages are between a ground voltage and a maximum voltage.
3. The driving calibration apparatus of the electrostatic MEMS scanning mirror according to claim 1 , wherein voltage differences between the reference voltages are the same.
4. The driving calibration apparatus of the electrostatic MEMS scanning mirror according to claim 1 , wherein the plane mirror is being swung around a first axis and a second axis, and when the voltage setting unit sequentially sets the different reference voltages to drive the plane mirror to swing around the first axis, the plane mirror is in a static state on the second axis.
5. The driving calibration apparatus of the electrostatic MEMS scanning mirror according to claim 1 , wherein the ideal projection positions are set to be a plurality of projection positions of light spots on the projected surface that are projected to by the laser beam, and the ideal projection positions have a constant interval spacing from each other.
6. A driving calibration method of an electrostatic MEMS scanning mirror, wherein the electrostatic MEMS scanning minor comprises a plane mirror for guiding a laser beam to project on a projected surface, the method comprising:
sequentially setting a plurality of different reference voltages to drive the plane mirror to swing;
sensing a plurality of projection positions on the projected surface corresponding to the plurality of different reference voltages that the laser beam projects to;
establishing a driving lookup table according to the reference voltages and the corresponding projection positions;
determining calibrated driving voltages respectively corresponding to a plurality of ideal projection positions according to the driving lookup table; and
driving the plane minor to swing according to the calibrated driving voltages.
7. The method according to claim 6 , wherein each of the reference voltages has a corresponding projection position.
8. The method according to claim 6 , wherein voltage differences between the reference voltages are the same.
9. The method according to claim 6 , wherein the plane mirror is being swung around a first axis and a second axis, when the voltage setting unit sequentially sets the different reference voltages to drive the plane mirror to swing around the first axis, the plane mirror is in a static state on the second axis.
10. The method according to claim 6 , wherein the ideal projection positions are set to be a plurality of projection positions of light spots on the projected surface that the laser beam projects to, and the ideal projection positions have a constant interval spacing from each other.