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arXiv · 2503.17925

Spectral filtering effect of diffraction gratings with a lens coupling to optical fibers

Seonjong Ryu·Jinpyo Jeong·Mintae Kang·Taemin Son·Andy Chong
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Abstract

We present a theoretical study of a spectral filter, which consists of a diffraction grating, a coupling lens, and an optical fiber. As the diffracted beam is highly dispersed spatially, coupling into an optical fiber naturally creates a Gaussian spectral filtering effect. Using ray transfer matrices, we derive simple equations to calculate the spectral filter bandwidth and the group velocity dispersion. This study offers insights for designing fiber-based spectral filters, particularly for mode-locked fiber lasers.

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Seonjong Ryu, Jinpyo Jeong, Mintae Kang, Taemin Son, Andy Chong. 2025-03-23. Spectral filtering effect of diffraction gratings with a lens coupling to optical fibers. https://arxiv.org/abs/2503.17925

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