Analysis of random grating period and amplitude errors in ultra-thin long-period grating

The effects of random fabrication errors on an ultra-thin long-period grati ng ale numerically investigated. The influences of the random grating perio d and random amplitude nodes on an optical bandpass filter based on an ultr a-thin long-period grating are introduced. It is found that the random peri od errors present severe degradation of the spectral performance of the ult ra-thin long-period grating The coupling intensity of the ultra-thin long-p eriod grating decays exponentially with even small grating period noises. O ur. simulation results may help manufacturers to analyze the quality of fab ricated long-period gratings and to point out future improvement directions . (C) 2001 John Wiley & Sons, Inc.