Abstract

Directional 2×2 couplers with coupling ratio insensitive to wavelength are required for branching/combining optical signals in a wide wavelength region. Such wavelength-insensitive couplers (WINC) have been realized in a fiber-optic configuration by fusing two single-mode fibers with slightly different parameters to each other and tapering them together.¹ However, this type of fiber-optic WINC configuration appears to have some limitations in terms of its reproducibility, productivity, and suitability to integration. A possible approach to overcome these problems is the use of waveguide technologies to form integrated-optic WINCs. This paper describes the novel design and fabrication of the waveguide WINCs by using high silica on Si technologies.^2,3

© 1990 Optical Society of America