Rockwell Automation 2755 StrataScan Bar Code Readers - Manual (Page 14)

2–2 Hardware Features
Publication 2755-6.13
Holographic Scanning Disc
The rotating holographic disc takes the place of a focusing lens, light
collection lens, and a rotating mirror. The disc contains 15 to 21
separate holographic sectors. Each sector has its own focal distance,
light collection aperture, and mirror scan angle. As the disc rotates,
each sector is operational, providing the reader an excellent
opportunity to scan a bar code symbol.
Scanning Element Receiving Elements
Large Area Receiver
(for long focal length
holographic lens) Small Area Receiver
(for short focal length
holographic lens)
Scanning Element