Holographically recorded gratings on microlenses for a miniaturized spectrometer array

We report on the investigation of refractive microlens arrays with diffract ive grating surfaces in the context of a microspectrometer array system. Th e elements fabricated combine the fairly large dimensions of the refractive microlens (990-mu m diam, 60-mu m height) with the submicron features of t he diffraction grating (1-mu m grating period) on one transmitting surface. The fabrication process of these elements was studied, as well as their pe rformance with respect to resolution and stray-light suppression. The maxim um resolution was 3 nm, and the stray-light suppression 25 dB. We present a concept for a system of miniaturized spectrometer arrays for chemical anal ysis. (C) 2000 Society of Photo-Optical Instrumentation Engineers. [S0091-3 286(00)03001-4].