An easy method for designing filters with equalized passband ripples of a given magnitude is proposed. The filter, which is made of two dielectric materials, comprises coupled half-wavelength resonators and multilayer mirrors. The filter design begins with the synthesis of the multimaterial filter prototype whose mirrors consist of quarter-wavelength layers. Optimal refractive indices of the layers in the prototype are obtained by a special optimization based on universal rules. The thicknesses of the mirrors’ layers in the final filter are computed using derived formulas. A design procedure example for silicon–air bandpass filters with a fractional bandwidth of 1% is described.
© 2014 Optical Society of America
Original Manuscript: March 26, 2014
Revised Manuscript: April 30, 2014
Manuscript Accepted: May 10, 2014
Published: June 6, 2014
B. A. Belyaev, V. V. Tyurnev, and V. F. Shabanov, "Design of optical bandpass filters based on a two-material multilayer structure," Opt. Lett. 39, 3512-3515 (2014)