Patent ID: 7522811

Claim:
A method comprising: producing an article that includes: a body with light-transmissive first and second wall parts; first and second inward surfaces on the first and second wall parts, respectively; the inward surfaces facing each other and being separated by a fluidic region that can contain fluid; first and second outward surfaces on the first and second wall parts, respectively; each outward surface facing away from the fluidic region; the inward and outward surfaces all being approximately parallel; and one or more light interface surfaces, each light interface surface being on one of the first and second wall parts and not being parallel to any of the inward and outward surfaces; the act of producing the article including: performing a complementary surface fabrication process to produce each of the inward and outward surfaces and a set of at least one of the light interface surfaces with a respective portion that has optical quality; the article being structured to operate as a sandwich waveguide with fluid in the fluidic region between the inward surfaces and with light entering the fluidic region through at least one of the set of light interface surfaces.