Oscillator device, optical deflector and image forming apparatus using the optical deflector

An oscillator device, comprising:

• an oscillation system including a first oscillator, a second oscillator, a first resilient supporting member configured to connect said first oscillator for torsional oscillation about a torsion axis relative to said second oscillator, and a second resilient supporting member configured to support said second oscillator for torsional oscillation about a torsion axis relative to a fixed member;
• driving means configured to drive said oscillation system;
• and
• drive control means configured to supply a driving signal to said driving means;
• wherein said oscillation system has at least two frequencies of natural oscillation mode around the torsion axis which include a first resonance frequency f1 and a second resonance frequency f2,
• wherein there is a relationship that f2 is approximately two-fold of f1,
• wherein Δf which is expressed as Δf=f2−f×f1 has a relationship of Δf<0, and
• wherein said drive control means supplies, to said driving means, a driving signal which is comprised of a driving signal based on synthesizing a first driving signal having a first driving frequency and a second driving signal having a second driving frequency, and which is such driving signal that, when a lower-frequency side driving frequency among the first and second driving frequencies is denoted by Df1 and a higher-frequency side driving frequency is denoted by Df2, it satisfies relationships
• Df1<f1
• Df2>f2
• Df1×2=Df2.