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Journal of the Optical Society of America A

Journal of the Optical Society of America A


  • Vol. 20, Iss. 1 — Jan. 1, 2003
  • pp: 130–137

Design of curved waveguides: the matched bend

Andrea Melloni, Paolo Monguzzi, Raffaella Costa, and Mario Martinelli  »View Author Affiliations

JOSA A, Vol. 20, Issue 1, pp. 130-137 (2003)

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A new criterion for the optimum design of curved dielectric waveguides is proposed. The bends designed according to this model are named matched bends. In the matched bend, the suitable choice of both bending radius and bending angle reduces the total losses of the bend and avoids the leaky-mode excitation at the end of the bend. For a given angle, a discrete number of bending radii that satisfy the matched bend criterion can be analytically determined. With respect to the lateral offset, matched bends are more robust to both fabrication tolerances and wavelength and can be realized in every technology. The reduction of the leaky-mode excitation at the output of the bend is a fundamental property when two or more components are cascaded. Ghost images in the spectral response, cross talk, and asymmetries of the transfer function are successfully reduced. Some examples that use buried, rib, ridge, and diffused waveguides are presented and discussed.

© 2003 Optical Society of America

OCIS Codes
(130.2790) Integrated optics : Guided waves
(130.3120) Integrated optics : Integrated optics devices
(230.3120) Optical devices : Integrated optics devices
(230.7370) Optical devices : Waveguides

Original Manuscript: April 19, 2002
Revised Manuscript: August 1, 2002
Manuscript Accepted: August 6, 2002
Published: January 1, 2003

Andrea Melloni, Paolo Monguzzi, Raffaella Costa, and Mario Martinelli, "Design of curved waveguides: the matched bend," J. Opt. Soc. Am. A 20, 130-137 (2003)

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