Binary amplitude holograms made from dyed photoresist.

A method for fabricating binary amplitude holograms from a dyed photoresist is described. It is of particular interest for holograms that are used as null optics in the form metrology of aspheric surfaces and wavefronts. A pigment that strongly absorbs light near 633 nm was dissolved in a positive photoresist and the dyed resist was spun onto silica glass substrates. Stable resist layers were obtained that were essentially opaque at 633 nm with little effect on the transmittance of the resist in the UV. A Fresnel zone plate was fabricated from the dyed resist layer using contact lithography, and its performance was demonstrated at 633 nm.