Toshiba had to solve a difficult problem: the same laser had to be able to read signals from two discs with different pit widths. Several possible solutions were considered.

Among the candidate solutions are an integrated two-lens switching system which consists of two lenses, one for CD, and the other for DVD, and a dual-focus pickup system in which a single lens is used to achieve focus for both CD and DVD.

With the integrated two-lens switching system, two lenses, one for CD and the other for DVD, are switched by rotating the lenses horizontally to read signals for each disc. Due to the difference of the specification of the wave length, CD-R is unreadable.

With the dual-focus pickup system, thanks to the adoption of a hologram lens, a single lens can achieve focus for both CD and DVD without being realigned, and read the signals. Due to the difference of the specification of the wave length, CD-R is unreadable.