Simple, inexpensive wavemeter implemented with a fused fiber coupler

摘要

A simple, inexpensive wavemeter for measuring the wavelength of optical fiber coupled light sources is described. We determined the wavelength by measuring the wavelength-dependent coupling coefficient of a fused fiber coupler. A prototype device covering the wavelength range of 1500-1600 nm was assembled and tested in the laboratory. The wavemeter had a wavelength uncertainty of less than 0.087 nm over a wavelength range of 1530-1570 nm. The dominant source of error in the test was found to be due to the presence of broadband amplified spontaneous emission (ASE) in the laser output. It is expected that the accuracy of the device can be increased significantly by the introduction of a band-limiting filter to reduce the ASE level.