Patent ID: 7492998

Claim:
A fused fiber bundle having a terminal section ending with an endface, the fused fiber bundle comprising: a glass tube; at least one spacer member having a selected shape inserted in the glass tube; and a plurality of optical fibers, each of the optical fibers having a terminal segment ending with a proximal end, and a distal end, said terminal segments being arranged between the glass tube and the at least one spacer member; wherein the glass tube surrounds the terminal segments of the optical fibers, wherein the terminal segments of the optical fibers are arranged substantially in parallel, wherein the terminal segment of each of the optical fibers is substantially fused to any adjacent optical fibers and the terminal segment of each optical fiber adjacent to the glass tube is substantially fused thereto, thereby forming the terminal section of the fused fiber bundle, and wherein the glass tube is a thick-walled tube, such that at the endface of the fused fiber bundle, the ratio of the cross-sectional area of the endface to the cross sectional area of the plurality of optical fibers is at least about 2.5.