Quantum DLT 2000 Handbook page 176

LGMR Technology
The cornerstone of the Super DLTtape technology platform is its use
of Laser Guided Magnetic Recording (LGMR). This unique technolo-
gy application will produce an advanced scalable platform designed to
meet an extraordinary range of storage requirements, and to support
multiple generations of products.
LGMR ensures higher cartridge capacities by allowing for the substan-
tial increase in the number of recording tracks and recording density
on the data surface of the media by servoing from optical targets on
the media's back side.
In the development of Super DLTtape technology, design engineers
aimed to advance the capabilities of many of the critical attributes of
magnetic recording. By using enhancements in tape formulations,
head designs, and recording channel technologies, they were able to
achieve increased recording densities and a substantial increase in
the number of tracks available for recording. However, by increasing
the number of tracks, more advanced servo techniques were
required to ensure efficiency. It was clear that all traditional magnet-
ic tape servo methods had a fundamental problem: they all used a
portion of the recording surface to store the servo track information.
The engineers created a design breakthrough: they designed and
developed technology to take advantage of the previously unused
backside of the media by laser-etching optically read servo tracks on
a specially formulated back coating. This design innovation – the
placing of magnetic data tracks on one side of the tape and indelible
optical guidance tracks on the other – provides increased storage
space on the magnetic side of the media. By introducing these
Quantum-refined optical tracking technologies, the servo tracking
capabilities of traditional magnetic systems have been greatly
improved. The result is the foundation of LGMR. (See Figure 17-2.)
17.8 SUPER DLTtape: THE FUTURE OF DLTtape TECHNOLOGY