A data card for storing individual data for the use of an exerciser, such as a stationary bicycle. The data card includes a base having a transparent plate and a photo intercepting film formed on the plate for intercepting light except for a plurality of portions. A plurality of removable light stopping...http://www.google.fr/patents/US5294786?utm_source=gb-gplus-shareBrevet US5294786 - Optical data card for an exerciser
