A microtiter stick for use in performing immunochemical tests has a solid plastic body and a row of shallow wells (26). Each well is in the form of a truncated hemisphere, the bottom of which is an optically clear, circular, transparent, concave lens surface (26'). The remainder of the truncated hemisphere...http://www.google.de/patents/US4956150?utm_source=gb-gplus-sharePatent US4956150 - Disposable microtiter stick
