An optical displacement sensor is provided according to one embodiment. The optical displacement sensor comprises a housing; a displacement member coupled to the housing, configured to contact an object under test and move based on displacement of the object under test; a light emitter coupled to the housing; an optical transducer coupled to the housing; and a reflecting surface coupled to the displacement member to reflect at least a part of the light emitted from the light emitter to the optical transducer, such that movement of the displacement member modifies intensity distribution of the light reflected to the optical transducer.