Optical tape drive that includes redundant optical heads to perform failure recovery

• Main Authors: MASTERS; JOHN R, POLLOCK; KEITH, MARTINEZ; A. RENE, LUTTRALL; JAMES R
• Format: Patent
• Language: English
• Published: 02.05.2000
• Edition: 7
• Subjects: INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS

An optical tape drive including redundant optical heads to continue reading and writing data to an optical tape in the event of failure of one or more optical heads. The optical tape drive includes a plurality of optical heads, each capable of reading data from and writing data to an optical tape, detection logic that detects failure of any of the optical heads and control apparatus. The control apparatus positions each of the optical heads along the width of the optical tape, controls each of the optical heads to either read or write data, receives and moves the optical tape, detects failure of any of the optical heads and performs failure recovery by continuing to read and write data with remaining optical heads. The data throughput rate during failure recovery may be the same as the normal rate for some operations, such as direct read after write. Several different optical head configurations are contemplated. In respective embodiments, the optical tape drive includes two head systems, four head systems, eight head systems, etc., where each head system includes one or more optical head units.