New types of in-line fiber filters whose core and cladding are composed of binary silica doped with either boron or fluorine are proposed. Utilizing dispersive characteristics of SiO2-B2O3 and SiO2-F systems, we demonstrate that an optical fiber, with borosilicate core and fluorosilicate cladding, shows short-pass filter response. Experimentally, we fabricated a short-pass filter fiber that could be used as a 1310/1550 nm WDM filter. We also propose theoretically that a long-pass filter could be obtained in a fiber structure whose core is fluorosilicate with borosilicate cladding. In a special long-pass filter structure, we found that the normalized frequency can be kept uniform over a wide wavelength range from 1200 to 1700 nm, which will be applied in wideband wavelength division multiplexing devices.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering