EYE-PIECE OPTICAL DEVICE Russian patent published in 1995 - IPC

FIELD: optical instrument engineering. SUBSTANCE: eye-piece of optical device has element made of light-refracting material. The first flat surface of the element is perpendicular to axis of sight of the eye-piece. The second flat surface is inclined to the first one at an angle which excesses over critical angle for total reflection. The third surface has shape of a sphere and is turned with its concavity to image. Holographic optical element is covered onto the spherical surface. The element is made in form of a set of quazieliptical rings with different optical densities. Shapes of the rings are defined by the relation given in the description of the invention. EFFECT: improved precision. 1 dwg