Drill bits and methods of measuring drill bit conditions are disclosed. A drill bit for drilling a subterranean formation comprises a bit bearing at least one cutting element and adapted for coupling to a drill string. The drill bit may also comprise a chamber formed within the bit and configured for maintaining a pressure substantially near a surface atmospheric pressure while drilling the subterranean formation. In addition, the drill bit may comprise at least one optical sensor disposed in the chamber and configured for sensing at least one physical parameter exhibited by the drill bit while drilling a subterranean formation.