Patents Assigned to Hughes Aircraft Company now known as Ragtheon Company
  • Patent number: 5825553
    Abstract: An improved eyepiece for an optical system. In general, the inventive eyepiece (10) includes a refractive element (16) and an optical arrangement for relaying the entrance pupil of the system to the refractive element. In a specific implementation, the optical arrangement includes a concave primary mirror (12) and a secondary mirror (14). The mirrors are mounted to communicate an image from the refractive element (16) to the entrance pupil (40). In the specific implementation, the refractive element (16) is one or more refractive lenses. The use of a reflective optical arrangement allows for the long eye relief. The placement of the entrance pupil close to the pupil of the lens allows for the use of a compact optical arrangement with high ratio of eye relief to effective focal length with a compact optical arrangement. The system affords minimal lateral chromatic aberration and good image quality.
    Type: Grant
    Filed: November 29, 1993
    Date of Patent: October 20, 1998
    Assignee: Hughes Aircraft Company now known as Ragtheon Company
    Inventor: Chungte W. Chen