Patent ID: 7423362

Claim:
A driving method of a piezoelectric transformer for applying voltage of a discontinuous rectangle wave, composed of a potential V 0 , a potential V H which is higher than the potential V 0 and a potential V L which is lower than the voltage V 0 , to a primary electrode of the piezoelectric transformer, wherein assuming one cycle is T, the discontinuous rectangle wave has such a configuration that a potential from a time 0 to a time ø is the potential V 0 , from the time ø to a time (T/6−ø) is the potential V H , from the time (T/6−ø) to a time (T/3+ø) is the potential V 0 , from the time (T/3+ø) to a time (T/2−ø) is the potential V L , from the time (T/2−ø) to a time (T/2+ø) is the potential V 0 , from the time (T/2+ø) to a time (2T/3−ø) is the potential V L , from the time (2T/3−ø) to a time (5T/6+ø) is the potential V 0 , from the time (5T/6+ø) to a time (T−ø) is the potential V H , and from the time (T−ø) to a time T is the potential V 0 , and a phase difference ø is 0≦ø≦T/12.