Line Width and Write Speed

Systems using YAG lasers are reported to have scan speeds of 40 cm/s [35] (using a 300 mW laser) He-Ne laser-addressed systems can provide about 40 mm/s (using an 8 mW laser) and 8 mW GaAs lasers also provide about 40 mm/s. 

In the earlier work with YAG lasers, line widths of 15-20 ftm were typical [6, 28, 35] (25 line pairs/mm), while in later work, line widths down to 3 io,m have been reported [23] in 9 pm thick films using a 12 mW He-Ne laser and a dye dissolved in the liquid crystal. However, 10 pm line widths are more typical [29]. 

A total erasure cycle, by electrical heating of the cell, is often accomplished in about 20 s [6, 35]. 

On screen, projected image contrast ratios of 8-20 1 have been reported [6, 28, 29, 35]. The contrast of scattering systems is critically dependent on the collection angle of the optics used, and so comparing data 

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