Beginning with a sheet of optically transparent material, one may fabricate a great many shaped optical wafers, each in the form of a thin and essentially flat piece of optical material having a narrow cross-sectional width relative to length, and a sharply narrowed tip at one end. The fabrication process involves passing a sheet of optically transparent material through one or more operational steps wherein cutting, shearing, embossing, microperforating, or a combination thereof is performed. The fabrication process may further include a cladding operation, a tip texturing operation, and an analyte-reactive reagent deposition operation. The completed optical wafers are separated and each may be mounted into a user-operated device along with systems for educing a fluid sample to be expressed from a living organism, for bringing the tip of the optical wafer into contact with the fluid sample, and for illuminating and assaying the fluid sample.