초록 ▼

A reticle plate provided with a reticle and three concentric circles of varying 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 pl

A reticle plate provided with a reticle and three concentric circles of varying 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.

대표청구항 ▼

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 th

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: orientation of the reticle generally in the direction to be established; aligning each one of the circles with one each of the visible objects to cause the objects to be simultaneously disposed on the circumference of the respective circles; and, marking the direction sought as being coincident with the intersection of the hairline elements.