Actuator and light scanning apparatus

Abstract

An actuator including a beam configured to support an object to be driven, and a drive source to which a drive signal is input, wherein the drive signal includes a drive waveform in a shape of sawtooth waveform, a rising of the drive waveform in the shape of sawtooth waveform includes a first staircase waveform and a second staircase waveform continuing from the first staircase waveform, the first staircase waveform generates oscillation of a ringing suppressing waveform for suppressing a ringing waveform to be generated in the second staircase waveform, and the object to be driven is driven to swing in a direction of rotating around the predetermined axis by driving the drive source.

What is claimed is: 
     
         1 . An actuator comprising:
 a beam configured to support an object to be driven; and   a drive source to which a drive signal is input,   wherein the drive signal includes a drive waveform in a shape of sawtooth waveform,   a rising of the drive waveform in the shape of sawtooth waveform includes a first staircase waveform and a second staircase waveform continuing from the first staircase waveform,   the first staircase waveform generates oscillation of a ringing suppressing waveform for suppressing a ringing waveform to be generated in the second staircase waveform, and   the object to be driven is driven to swing in a direction of rotating around the predetermined axis by driving the drive source.   
     
     
         2 . The actuator according to  claim 1 ,
 wherein the beam includes a plurality of beams extending in a direction vertical to the predetermined axis, and   adjacent ends of adjacent beams from among the plurality of beams are connected by a turnback so as to form a zigzag-like meandering structure as a whole.   
     
     
         3 . The actuator according to  claim 1 ,
 wherein the beam is a drive beam, on a front surface of which a drive source is formed, the beam being a drive beam configured to swing the object to be driven.   
     
     
         4 . The actuator according to  claim 1 ,
 wherein ringing generated by the first staircase waveform and ringing generated by the second staircase waveform mutually cancel.   
     
     
         5 . The actuator according to  claim 1 ,
 wherein a height of the first staircase waveform and a height of the second staircase waveform are substantially same.   
     
     
         6 . The actuator according to  claim 1 ,
 wherein a length of the first staircase waveform is other than n times of a ringing wavelength λr of ringing generated by first staircase waveform where n is a positive integer.   
     
     
         7 . The actuator according to  claim 6 ,
 wherein the length of the first staircase waveform is 0.5 λr.   
     
     
         8 . The actuator according to  claim 1 ,
 wherein a rising section of the sawtooth waveform is a main scan section of scanning by the actuator.   
     
     
         9 . A light scanning apparatus comprising:
 a mirror including a light reflection surface for reflecting light;   a mirror supporting body configured to support the mirror;   a drive beam configured to support the mirror supporting body, the drive beam including a plurality of drive beams extending in a direction vertical to a predetermined axis, adjacent ends of adjacent drive beams from among the plurality of drive beams being connected by a turnback so as to forma zigzag-like meandering structure as a whole; and   a drive source to which a drive signal is input, the drive source being formed on a front surface of the plurality of drive beams,   wherein the drive signal includes a drive waveform in a shape of sawtooth waveform,   a rising of the drive waveform in the shape of sawtooth waveform includes a first staircase waveform and a second staircase waveform continuing from the first staircase waveform,   the first staircase waveform generates oscillation of a ringing suppressing waveform for suppressing a ringing waveform to be generated in the second staircase waveform, and   the mirror supporting body is driven to swing in a direction of rotating around the predetermined axis by driving the drive source.