ASTRO POSITION COORDINATOR Russian patent published in 1998 - IPC

FIELD: observation of heavenly bodies on board ships for determination of geographic coordinates. SUBSTANCE: telescope has illuminated field of view with reticule and two optical channels created by beam splitters before objective; one channel is provided with measuring prism fitted with read-off device; telescope is provided with two Dove prisms (reversing prisms) arranged in second optical channel. One prism is rigidly connected with body of instrument and its reflecting face is parallel to one of cross-hairs in field of view of telescope; second prism provided with plumb bob is free to turn about optical axis of channel by gravity. When vertical of plumb bob lies in sighting plane, images produced by both channels coincide, sighting plane of instrument lies in plane of vertical of heavenly body whose images is located on vertical cross-hairs in field of vies of instrument. EFFECT: simplification of observation at sea; effective determination of navigational parameters without angular measurements. 1 dwg