Patent ID: 6453094
Filing Date: 2002-09-17
Classification: G02B

Abstract:
An optical fiber coupling device comprising:a first multiple core fiber, a first core of said first multiple core fiber having an effective index of refraction and propagation constant different from an effective index of refraction and propagation constant of a second core of said first multiple core fiber; and a second multiple core fiber, a first core of said second multiple core fiber having an effective index of refraction and propagation constant different from an effective index of refraction and propagation constant of a second core of said second multiple core fiber, the effective index of refraction and propagation constant of the second core of the second multiple core fiber being substantially equal to the effective index of refraction and propagation constant of the second core of the first multiple core fiber; wherein said first and second multiple core fibers are aligned and fused together such that the second core of the first multiple core fiber is in sufficient proximity to the second core of the second multiple core fiber as to obtain overlapping of mode fields and efficient coupling of propagating optical signals therebetween and such that the first core of the first multiple core fiber is sufficiently separated from the first core of the second multiple core fiber as to obtain weak or substantially no coupling of propagating optical signals therebetween, whereby any optical signal propagating along the first core of the first multiple core fiber achieves low loss.