An improved surgical cassette for controlling intraocular pressure during ophthalmic surgery. One illustrative application is in the context of authenticating the identity of a subject by verifying items of identifying information stored by, or accessible through, a plurality of data sources. The apparatus also includes a measuring device which is capable of continuously measuring the surface of the wafer during polishing of the surface of the wafer. In addition, the relay device determines whether data needed to be generated is required to be regenerated or not and, only when it is determined that the already stored data is old and regeneration of the data is needed, regenerates the data using the data that is calculation source data. The selected diameter of each annular ring member increases with distance from the neck portion.