Further qualifications are imposed on the fluorescent material when a recordable (not just readable) system is contemplated. The fluorescence must be either capable of being switched on or off, or it must be susceptible to a threshold at which it stops changing once it is written on. Thermal bleaching techniques attempt to solve this problem by using a fluorescent substance that loses its fluorescence as soon as it's written on (becoming a permanent layer).

So far, much has been accomplished to meet all these criteria. The fluorescent material being produced today is stable, resulting in zero corruption during read-out. Lasers of 650nm are being used, with 680nm peaks in the fluorescent light. Conversion efficiency has hit more than 90%, and saturation levels are at 1MW/cm², which bests the intensity of the system's read power.

To date, Constellation 3D's research in this field has proven the viability of a 50-layer ClearCardTM ROM. Its storage capacity is one terabyte, and its access speed can reach 1 gigabit/second. Other products include a 10-layer, 1-gigabyte FMD ClearCard"!, designed for inclusion in laptops, hand-held computers, digital cameras, and cell phones, among other small-size, high-capacity devices. The 10-layer FMD ROM, on the other hand, would be capable of storing up to 140 gigabytes -- a major improvement on the current 18-gig capacity of DVD players. This technology would be able to store up to 20 hours of HDTV film.

As if that weren't enough, Constellation 3D plans to make all its new multilayer devices backward-compatible, so that your brand-new multilayer drive will have no trouble reading your old CDs and DVDs. As conventional, magnetic-disk technology runs into its own data-corrupting limitations, fluorescent multilayer systems are likely to step in and revolutionize the market with technology that is not only more stable than its forerunner -- but also boasts much greater, faster storage capacities.