Holographic Diffraction Gratings Recorded in Photoresist

Abstract

Good quality diffraction gratings have been produced by recording straight, parallel interference fringes in positive-working photoresist. The interference fringes are formed by overlapping two collimated beams of light from an Argon Ion laser at an angle. The photoresist is coated onto glass blanks by spinning, and after exposure is processed to give a periodic film thickness variation corresponding to the grooves of a diffraction grating. Gratings up to 6 cm diameter and with up to 3000 lines per mm have been produced in this way.