Holographic laser scanner and rangefinder
US5471326A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1993 |
| Grant date | Nov 28, 1995 |
| Priority date | — |
| Expiry date | Apr 30, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03H2270/22
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A holographic optical element (HOE) includes a substrate structure having rotational symmetry with respect to a rotational axis for rotatively supporting at least two holograms. A first hologram on the substrate structure in the path of a normally incident beam diffracts the beam by a first acute angle and in a first radial direction from the rotational axis to a first redirected path. A second hologram on the substrate structure in the first redirected path diffracts the beam by a different second acute angle and in an opposite second radial direction from the rotational axis to a second redirected path. As a result, the two holograms may be used to achieve a second redirected path at an angle to the rotational axis that has a size which is the difference between the size of the first angle and the size of the second angle. The substrate structure may include first, second, and third disc-shaped substrates bonded together so that the third substrate is in between the first and second substrates, and a thin-film interference filter may be included on the third substrate to suppress zero-order leakage through the first hologram. The filter element may include one of a dielectric sta…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.