DEVICE OF ANGLE MEASURING INSTRUMENT FOR READING BY LIMBS Russian patent published in 1995 - IPC

FIELD: optical instrumentation engineering. SUBSTANCE: device includes microscope, two objective lenses with common focal plane, three reflecting elements located in vertexes of right-angled isosceles triangle and diaphragm. Objective lenses are put on leg of triangle. Plane of diaphragm is matched with common focal plane of objective lenses. Two reflecting elements in the form of right-angled prisms with one reflecting face are arranged either on one of legs or on hypotenuse of triangle and third reflecting element has even number of reflecting faces. If first two reflecting elements are placed on leg of triangle then third element is manufactured in the form of pentaprism with optical length of path of rays equal to optical length of path of rays in one of right-angled prisms located at vertex of triangle. Diaphragm is positioned on other leg of triangle. If first two reflecting elements are located on hypotenuses of triangle then third reflecting element is fabricated in the form of two similar hemipentaprisms mounted in symmetry in vertex of right angle of triangle and diaphragm is put in vertex of right angle and is located between hemipentaprisms. EFFECT: improved authenticity of measurements. 4 cl, 3 dwg