An oscillator device including an oscillation system with oscillators and torsion springs, a driving member for driving the oscillation system, and a drive control member for supplying a driving signal to the driving member, the oscillation system having at least a first oscillation mode and a second oscillation mode, the second oscillation mode having an angular frequency approximately n-fold the angular frequency of the first oscillation mode where n is an integer, the driving member driving the oscillation system so that it simultaneously oscillates in the first and second oscillation modes, wherein a natural angular frequency calculating member calculates the natural angular frequency of the second oscillation mode based on an output signal from a photodetector, being outputted at a timing whereat the reflection light passes over the photodetector.