Oscillating device, electric potential measuring device, light deflecting device, and image forming apparatus

A light deflecting device comprising:

• a movable member that is vibratable;
• a fixed section that is provided opposite to the movable member;
• a driving unit configured to drive the movable member at a predetermined driving frequency;
• at least two electrodes configured to generate a first signal corresponding to a drive state of the movable member, with at least one electrode being provided on the movable member, and with at least one electrode being provided on the fixed section;
• and
• a light deflecting element,
• wherein the light deflecting element is provided on the movable member, and
• wherein the first signal is input into the driving unit, and the driving unit controls the driving of the movable member on the basis of the input first signal.

An electric potential measuring device comprising:

• a movable member that is vibratable;
• a fixed section that is provided opposite the movable member;
• a driving unit configured to drive the movable member at a predetermined driving frequency;
• and
• at least two electrodes configured to generate a first signal corresponding to a drive state of the movable member, with at least one electrode being provided on the movable member, and with at least one electrode being provided on the fixed section,
• wherein the first signal is input into the driving unit, and the driving unit controls the driving of the movable member on the basis of the input first signal.