Optical scanner apparatus and optical scanner control apparatus

Abstract

An optical scanner apparatus includes first and second torsion beams which support a mirror support portion supporting a mirror from both sides in an axial direction; first and second horizontal driving beams configured to include first and second horizontal driving sources, respectively, a connecting beam; a first piezo-electric sensor; first and second sensor interconnects connected to one of and the other of an upper electrode and a lower electrode of the first piezo-electric sensor, respectively, the first sensor interconnect and the second sensor interconnect being formed to extend toward the first horizontal driving beam and the second horizontal driving beam, respectively.

What is claimed is: 
     
         1 . An optical scanner apparatus comprising:
 a mirror;   a mirror support portion which supports the mirror;   a first torsion beam and a second torsion beam which support the mirror support portion from both sides in an axial direction around which the mirror support portion is oscillated by torsions of the first torsion beam and the second torsion beam;   a first horizontal driving beam and a second horizontal driving beam provided to interpose the mirror and the mirror support portion therebetween and configured to include a first horizontal driving source and a second horizontal driving source, respectively, for oscillating the mirror and the mirror support portion around the axial direction;   a connecting beam that connects one side of the first horizontal driving beam and the second horizontal driving beam to the first torsion beam;   a first piezo-electric sensor including a lower electrode, a piezo-electric element and an upper electrode formed in this order on the connecting beam and configured to detect a displacement of the connecting beam by an oscillation of the first torsion beam and the second torsion beam around the axial direction when the mirror is being oscillated by driving voltages applied to the first horizontal driving source and the second horizontal driving source of the first horizontal driving beam and the second horizontal driving beam, respectively;   a first sensor interconnect and a second sensor interconnect connected to one of the upper electrode and the lower electrode of the first piezo-electric sensor and the other of the upper electrode and the lower electrode of the first piezo-electric sensor, respectively,   the first sensor interconnect and the second sensor interconnect being formed to extend toward the first horizontal driving beam and the second horizontal driving beam, respectively.   
     
     
         2 . The optical scanner apparatus according to  claim 1 , further comprising:
 a first drive interconnect for providing the driving voltage to the first horizontal driving source formed to extend along the first sensor interconnect; and   a second drive interconnect for providing the driving voltage to the second horizontal driving source to extend along the second sensor interconnect, and   wherein a distance at which the first drive interconnect and the first sensor interconnect extend along with each other and a distance at which the second drive interconnect and the second sensor interconnect extend along with each other are substantially the same.   
     
     
         3 . The optical scanner apparatus according to  claim 1 , further comprising:
 a first drive interconnect for providing the driving voltage to the first horizontal driving source formed to extend along the first sensor interconnect;   a second drive interconnect for providing the driving voltage to the second horizontal driving source to extend along the second sensor interconnect;   a first guard pattern connected to a ground terminal and provided between the first drive interconnect and the first sensor interconnect; and   a second guard pattern connected to a ground terminal and provided between the second drive interconnect and the second sensor interconnect.   
     
     
         4 . The optical scanner apparatus according to  claim 3 ,
 wherein the first guard pattern is formed at an entire portion between the first drive interconnect and the first sensor interconnect, and   the second guard pattern is formed at an entire portion between the second drive interconnect and the second sensor interconnect.   
     
     
         5 . The optical scanner apparatus according to  claim 1 , further comprising:
 a movable frame which surrounds the mirror, the mirror support portion, the first torsion beam, the second torsion beam, the first horizontal driving beam, the second horizontal driving beam, and the connecting beam,   a first vertical driving beam and a second vertical driving beam provided to interpose the movable frame therebetween, respectively connected to the movable frame and configured to include a first vertical driving source and a second vertical driving source, respectively, for oscillating the mirror and the mirror support portion in a direction perpendicular to the axial direction; and   a second piezo-electric sensor including a lower electrode, a piezo-electric element and an upper electrode formed in this order on the first vertical driving beam, and configured to detect a displacement of the first vertical driving beam when the mirror is being oscillated by a driving voltage applied to the first vertical driving source of the first vertical driving beam.   
     
     
         6 . The optical scanner apparatus according to  claim 5 , further comprising:
 a third sensor interconnect and a fourth sensor interconnect connected to one of the upper electrode and the lower electrode of the second piezo-electric sensor and the other of the upper electrode and the lower electrode of the second piezo-electric sensor, respectively such that the third sensor interconnect and the fourth sensor interconnect are formed to extend along the first sensor interconnect,   a first drive interconnect for providing the driving voltage to the first horizontal driving source formed to extend along the first sensor interconnect;   a second drive interconnect for providing the driving voltage to the second horizontal driving source to extend along the second sensor interconnect;   a third drive interconnect or  210 B ( 203 ) for providing the driving voltage to the first vertical driving source formed to extend along the first sensor interconnect;   a first guard pattern connected to a ground terminal and provided to separate the first sensor interconnect, the third sensor interconnect and the fourth sensor interconnect from the first drive interconnect and the third drive interconnect; and   a second guard pattern connected to a ground terminal and provided between the second drive interconnect and the second sensor interconnect.   
     
     
         7 . The optical scanner apparatus according to  claim 6 , further comprising:
 a third piezo-electric sensor including a lower electrode, a piezo-electric element and an upper electrode formed in this order on the second vertical driving beam, and configured to detect a displacement of the second vertical driving beam when the mirror is being oscillated by a driving voltage applied to the second vertical driving source of the second vertical driving beam;   a fifth sensor interconnect and a sixth sensor interconnect connected to one of the upper electrode and the lower electrode of the third piezo-electric sensor and the other of the upper electrode and the lower electrode of the third piezo-electric sensor, respectively such that the fifth sensor interconnect and the sixth sensor interconnect are formed to extend along the second sensor interconnect; and   a fourth drive interconnect for providing the driving voltage to the second vertical driving source formed to extend along the second sensor interconnect, wherein   the first guard pattern and the second guard pattern are formed to extend from points where the first sensor interconnect and the third sensor interconnect and the fourth sensor interconnect start to extend along with each other, and where the second sensor interconnect and the fifth sensor interconnect and the sixth sensor interconnect start to extend along with each other, respectively.   
     
     
         8 . The optical scanner apparatus according to  claim 1 ,
 wherein the first horizontal driving source and the second horizontal driving source are driven by driving voltages whose phases are opposite from each other.   
     
     
         9 . An optical scanner control apparatus comprising:
 the optical scanner apparatus according to  claim 1 ; and   a noise reduction unit that generates a first noise equality component signal and a second noise equality component signal from a first driving voltage applied to the first horizontal driving source and a second driving voltage applied to the second horizontal driving source, respectively, and removes a noise component from an output of the piezo-electric sensor based on the first noise equality component signal and the second noise equality component signal.   
     
     
         10 . The optical scanner control apparatus according to  claim 9 ,
 wherein the noise reduction unit includes a first gain-phase adjustment unit and a second gain-phase adjustment unit corresponding to the first driving voltage and the second driving voltage, respectively, and   the first noise equality component signal is generated by adjusting the amplitude and the phase of the first driving voltage by the first gain-phase adjustment unit, and   the second noise equality component signal is generated by adjusting the amplitude and the phase of the second driving voltage by the second gain-phase adjustment unit.   
     
     
         11 . The optical scanner control apparatus according to  claim 10 ,
 wherein the amplitude and the phase of the first noise equality component signal is adjusted to be equal to the amplitude and the phase of a signal output from the first piezo-electric sensor when the first driving voltage is applied to the first horizontal driving source, the second driving voltage having a frequency by which the mirror is not oscillated when the second driving voltage is applied to the first horizontal driving source, and   the amplitude and the phase of the second noise equality component signal is adjusted to be equal to the amplitude and the phase of a signal output from the first piezo-electric sensor when the second driving voltage is applied to the first horizontal driving source, the second driving voltage having a frequency by which the mirror is not oscillated when the second driving voltage is applied to the first horizontal driving source.   
     
     
         12 . The optical scanner control apparatus according to  claim 9 ,
 wherein the noise reduction unit includes   an adding circuit that adds the first noise equality component signal and the second noise equality component signal, and   a subtracting circuit that subtracts an adding result of the first noise equality component signal and the second noise equality component signal from the output of the piezo-electric sensor.   
     
     
         13 . The optical scanner control apparatus according to  claim 10 ,
 wherein the noise reduction unit includes   a control unit that generates the first noise equality component signal and the second noise equality component signal by controlling the first gain-phase adjustment unit and the second gain-phase adjustment unit from the first driving voltage and the second driving voltage, respectively.   
     
     
         14 . An optical scanner apparatus comprising:
 a mirror;   a mirror support portion which supports the mirror;   a first torsion beam and a second torsion beam which support the mirror support portion from both sides in an axial direction around which the mirror support portion is oscillated by torsions of the first torsion beam and the second torsion beam;   a first horizontal driving beam and a second horizontal driving beam provided to interpose the mirror and the mirror support portion therebetween and configured to include a first horizontal driving source and a second horizontal driving source, respectively, for oscillating the mirror and the mirror support portion around the axial direction;   a connecting beam that connects one side of the first horizontal driving beam and the second horizontal driving beam to the first torsion beam;   a first piezo-electric sensor and a fourth piezo-electric sensor each including a lower electrode, a piezo-electric element and an upper electrode formed in this order on the connecting beam and configured to detect a displacement of the connecting beam by an oscillation of the first torsion beam and the second torsion beam around the axial direction when the mirror is being oscillated by driving voltages applied to the first horizontal driving source and the second horizontal driving source of the first horizontal driving beam and the second horizontal driving beam, respectively;   a first sensor interconnect and a second sensor interconnect connected to one of the upper electrode and the lower electrode of the first piezo-electric sensor and the other of the upper electrode and the lower electrode of the first piezo-electric sensor, respectively;   a seventh sensor interconnect and an eighth sensor interconnect connected to one of the upper electrode and the lower electrode of the fourth piezo-electric sensor and the other of the upper electrode and the lower electrode of the fourth piezo-electric sensor, respectively;   a first drive interconnect for providing the driving voltage to the first horizontal driving source; and   a second drive interconnect for providing the driving voltage to the second horizontal driving source,   the first sensor interconnect, the second sensor interconnect, the seventh sensor interconnect and the eight sensor interconnect being formed to extend toward one of the first horizontal driving beam and the second sensor interconnect and the first drive interconnect and the second drive interconnect being formed to extend toward the other of the first horizontal driving beam and the second sensor interconnect.