A double-sided optical disc, such as a DVD-18 disc, is formed with data
tracks on each layer. The tracks on one side are oriented along one
spiral while the tracks on the other side are oriented along a second
spiral, the two spirals being oriented in opposite directions as viewed
from the respective sides. A player with two laser read heads is provided
for reading the disc. Each laser read head is disposed adjacent to a
respective disc side. The data is read from the two sides, either in
sequence from one side and then the other, simultaneously, or in some
alternating fashion.