Holographic scanning system
Holographic disk scanner
Holographic scanner disc with different facet areas
Light-beam scanning apparatus
Trifocal lens for a laser instrument
Multidirectional holographic scanner
Optical scanning system for a bar code reader Patent #: 4999482
ApplicationNo. 562865 filed on 08/06/1990
US Classes:235/462.34, Hologram235/462.06, Light level adaptation235/462.43Specified housing or mounting detail
ExaminersPrimary: Shepperd, John W.
Attorney, Agent or Firm
Foreign Patent References
International ClassG06K 007/10
Foreign Application Priority Data1989-08-04 JP
AbstractA bar code reader includes a hologram receiving a scanning light beam in sequence from a scanning light beam source for directing the scanning light beam to a bar code to be read along one path so that the bar code is scanned with the scanning laser beam in two-dimensional directions, and for guiding the scanning light beam to a photo-detector along the same path after the scanning light beam is reflected from the bar code, a condenser lens disposed in an optical system between the photo-detector and the hologram for collecting the reflected scanning light beam into the photo-detector, and a light blocking member disposed in an optical system between the condenser lens and the hologram for blocking unwanted light from the photo-detector, which unwanted light advances toward an incident side of the hologram on which the scanning light beam is directed.