Gratings have been used as Bragg reflectors in integrated optics for a variety of the applications. We report here a method of forming novel curved-line gratings and analyze their use for imaging in optical circuits and as the resonators in diode lasers.
P. K. Tien, "Method of forming novel curved-line gratings and their use as reflectors and resonators in integrated optics," Opt. Lett. 1, 64-66 (1977)