Patent ID: 7646946
Filing Date: 2010-01-12
Classification: G01D,G02B

Abstract:
1. A sensor for measuring strain in a material to which the sensor is attached, the sensor including: a reflector body with a reflective surface; an optical fiber probe including a first multimode optical fiber for transmitting light through the fiber and emitting light from an end of the fiber and at least one other multimode optical fiber for receiving light reflected by the reflector body; the reflective surface being spaced apart at a distance d from the end of the multimode optical fibers and positioned to receive the light emitted from the end of the first multimode optical fiber and to reflect at least a portion of the light into the end of the at least one other multimode optical fiber; and a housing affixed to the optical fiber probe at a first location and affixed to the reflector body at a second location, the distance L between the first location and the second location being greater than the distance d, wherein in operation, the housing is affixed to the material, strain in the material is transmitted to the housing and causes a change in the distance d between the multimode optical fiber ends and the reflective surface, and said change in the distance d modulates the amount of light received in the at least one other multimode optical fiber.