Holographic disk scanners for bow-free scanning.

Scan loci of holographic disk scanners are investigated. Bow-free scanning conditions are derived for holographic disk scanners employing generalized holographic zone plates. Hologram disk design and a holographic technique to generate the generalized holographic zone plates are described. Experimentally, scanning with less than ±100-μm bow deviation is demonstrated for a 40-cm scan length by using this disk design method.