Optical force sensor device with reflective displacement measurement

There is provided a sensor device to detect a force sense with a smaller and simpler mechanism. The sensor device includes: a force acting portion exposed from an opening provided on an exterior portion and attached to an inside of the exterior portion via a flexible body; a reflection space of which at least two surfaces are surrounded by a first mirror provided on an inner bottom surface of the exterior portion and a second mirror provided on a surface of the force acting portion or flexible body, the surface facing the first mirror; and a light source unit configured to emit light to the reflection space; and an imaging unit provided on the inner bottom surface of the exterior portion and configured to capture an image including a force sense detection region in which reflection light of the light emitted from the light source unit is seen.