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AssigneeThe United States of America as represented by the Secretary of the Army
InventorsMichael M. McDonnell, Donald P. Dere
Estimating the term…
A reticle plate provided with a reticle and three concentric circles of ving diameter and methods of use thereof, the invention allows a user to establish a north-oriented or south-oriented line by alignment of selected circumpolar stars with the circles. The circles are located on the reticle plate in positions determined by angles which exist between the celestial north (or south) pole and the particular low-magnitude circumpolar stars chosen as sighting points, the radii of the circles being directly proportional to the objective lens focal length of the theodolite or optical instrument within which the plate is used. A first method of the invention allows unambiguous location of the north or south pole by alignment of each of three selected stars with one each of the three circles. A second method provides data to a user sufficient to locate the pole by alignment of innermost and outermost circles respectively with one each of two of the selected stars.
In an optical aiming apparatus, a transparent reticle disc having visible indicia carried by the disc, the indicia comprising:
A method for location of a direction having a predetermined relationship to selected visual objects using an optical aiming reticle including intersecting hairline elements in a plurality of circles having the intersection of the hairline elements as a common center, each circle being disposed on the reticle in a location alignable with one of the visible objects, comprising:
Dependencies are inferred from the claim text.