Light collection from fluorescence-based biochips by holographic diffractive optical elements

Abstract

A fluorescence-based biochip with an integrated holographic diffractive optical element on its underside is presented. The diffractive element is a thick volume hologram written into a layer of photopolymer recording material. The element acts as a collector of the spatially anisotropic fluorescence light emitted from surface-bound fluorophores and redirects the light to a CCD detector. The holographic lithography setup used to fabricate the diffractive elements is described. The performance of the diffractive elements to enhance the light collection is demonstrated.