109results about How to "Improve negative effects" patented technology

The invention relates to an optical fiber large in effective area. The optical fiber large in the effective area comprises a fiber core layer and a covering layer. The optical fiber large in the effective area is characterized in that the fiber core layer comprises an inner core layer and an outer core layer, the radius r1 of the inner core layer is 1 to 4 microns, a relative refractive index difference delta 12 of the inner core layer to the outer core layer meets the condition that -0.2% <= delta 12 < 0%, the relative refractive index difference of the inner core layer to the outer core layer is invariant or gradually increased along with increasing of the radius, the radius r2 of the outer layer is 4 to 7 microns, and the relative refractive index difference delta 2 of the outer core layer is -0.15 % to 0.05 %; the covering layer comprises an inner covering layer, a sunk concave covering layer and an outer covering layer, the inner covering layer covers the fiber core layer, the radius r3 of the inner covering layer is 7 to 20 microns, the relative refractive index difference delta 3 is within the range of -0.5 % to -0.1 %, the radius r4 of the sunk concave covering layer is 12 to 40 microns, the relative refractive index difference delta 4 is within the range of -1.0 % to -0.3 %, and the relative refractive index difference delta 5 is within the range of -0.2% to -0.4%. The optical fiber large in the effective area has a large effective area, quite low transmission loss and good curve characteristics, and is particularly suitable for application of a long-distance high-speed large-volume communication system.