Optical grating and method of fabricating an optical grating

摘要

PCT No. PCT/GB93/00043 Sec. 371 Date Jun. 15, 1994 Sec. 102(e) Date Jun. 15, 1994 PCT Filed Jan. 11, 1993 PCT Pub. No. WO93/14424 PCT Pub. Date Jul. 22, 1993An optical grating includes a sequence of grating lines, the sequence being such that each grating line is centered on a position which is an integer multiple of a line spacing distance from a datum position on the grating, the sequence of grating lines is non-periodic and the sequence of grating lines is formed from N concatenated subsequences. Each subsequence includes a series of one or more instances of a respective grating line pattern. Such an optical grating has a structure that is more amenable to calculation of the grating lines necessary to achieve a desired characteristic. A method of calculating and fabricating such a grating is also disclosed.