Patent ID: 6128427
Filing Date: 2000-10-03
Classification: G02B,G02F

Abstract:
A tunable optical grating device comprising:an optical grating comprising a length of optical fiber having a plurality of spaced optical grating elements along the fiber:a first magnet attached to said grating body, and at least second and third magnets fixed in relation to said grating, said second and third magnets spaced apart by a gap, said first magnet capable of movement between said second magnet and said third magnet by stressing said fiber, the extent of the movement of said first magnet determined by said gap,and at least one of said magnets being switchable in response to an applied magnetic field whereby said first magnet is latchably switched between said second and third magnets, thereby switching said grating between two strain states; anda guide to limit twisting of said fiber.