Observation port assembly
Patent 4050792 Issued on September 27, 1977. Estimated Expiration Date: 
September 27, 1994. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
September 27, 1994. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 1708746 2491758 3526452 3910676 InventorAssigneeApplicationNo. 05/653609 filed on 01/29/1976US Classes:359/504, Wide angle (e.g., door peep)359/819, Lens mounts359/894OPTICAL APERTURE OR TUBE, OR TRANSPARENT CLOSUREExaminersPrimary: Corbin, John K.Assistant: de los Reyes, B. W. Attorney, Agent or FirmForeign Application Priority Data1975-03-12 SWAbstractAn observation port assembly, arranged to be attached to a door and to permit a panoramic view with a maximum field of view of the area outside the door, including a boxshaped part, attachable to the outside surface of the door, having at least two optical viewing elements with wide angle properties arranged with the viewing oculars adjacent to each other and viewable from the inside of the door, the optical axis of said elements being arranged in a predetermined angle relationship between to adjacently arranged elements. | |
