发明授权
- 专利标题: Holographic laser scanner and rangefinder
- 专利标题(中): 全息激光扫描仪和测距仪
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申请号: US56218申请日: 1993-04-30
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公开(公告)号: US5471326A公开(公告)日: 1995-11-28
- 发明人: James T. Hall , Arthur B. O'Connor , Susan M. Raffensperger , Seymour Levine
- 申请人: James T. Hall , Arthur B. O'Connor , Susan M. Raffensperger , Seymour Levine
- 申请人地址: CA Los Angeles
- 专利权人: Northrop Grumman Corporation
- 当前专利权人: Northrop Grumman Corporation
- 当前专利权人地址: CA Los Angeles
- 主分类号: B64D45/08
- IPC分类号: B64D45/08 ; G02B26/10 ; G02B5/32 ; G02B5/28 ; G02B27/42
摘要:
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 stack, a transmission hologram, or a reflectance hologram. The first hologram may be imprinted to achieve total internal reflection of zero-order leakage through the second hologram. An additional interference filter may be included on either the output face of the HOE or on a separate window element in order to reflects any zero-order leakage from the second hologram. The HOE may also have Schmidt-type aberration correction superimposed on at least one of the holograms to compensate for spherical aberrations from an all spherical Cassegrain type of telescope.
公开/授权文献
- US6108603A Navigation system using position network for map matching 公开/授权日:2000-08-22
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