Microphone

A microphone comprising:

• a vibration member having a plate shape and formed so as to have elasticity and cause bending due to sound waves;
• a case having a depressed groove, which forms an air layer between the depressed groove and the vibration member since the vibration member is stacked on an upper part thereof, and coupled to the upper part of the depressed groove such that the vibration member is vibrated by sound waves;
• and
• a vibration detection unit provided on the vibration unit and the case and measuring the vibration of the vibration member vibrating by sound waves on the case,
• wherein the vibration sensing unit includes
• a first grating unit formed to protrude in the horizontal direction on the vibration unit and of which location is changed with the vibration of the vibration unit,
• a second grating unit of which location is fixed while engaging with the first grating unit on the case,
• a light source provided on the case and emitting light toward the first grating unit or the second grating unit, and
• a light detecting unit receiving light reflected from the first grating unit or the second grating unit or passing between the first grating unit and the second grating unit to measure the vibration of the vibration unit.