Data retrieval method and apparatus

Data storage and retrieval system employing balanced magnetic ci

Data storage card having a non-magnetic substrate and data...

Data storage card having both linear and annular data regions

Data storage card having both linear and annular data regions

Data structure encoded on a surface of an object

Data structure for an optical reader

Data symbol reader

Data symbol reader

Data symbol reader and method including data symbol position eva

Data symbol reader including adjustable trigger switch unit

Data symbol reader utilizing ambient light illumination

Data symbol reader with an observation window

Data symbol reader with observation window

Data symbol reading apparatus

Data symbol reading device

Data symbol reading device

Data system and method for accessing a computer network...

Data system employing wallet-size optical card

Data verification method and magnetic media therefor