Reflex copier lens

An optical system of a reflex copier lens including a combination of glass and plastic elements, at least one of the elements being plastic and having aspheric surfaces, the system having substantially the following specifications:

• ______________________________________ EFL = 7.5436 inches (191.61mm) Half Angle of Field = 25.34 degrees Aperture = f/5.03 (All dimensions in Inches) Lens Radii Thickness Spacing N.sub.D V ______________________________________ L.sub.1 R.sub.1 = INF. T.sub.1 = .2350 1.522 59.5 R.sub.2 = INF. S.sub.1 = .0100 L.sub.2 R.sub.3 = +2.3490 T.sub.2 = .4046 1.522 59.5 R.sub.4 = -6.3260 S.sub.2 = .0100 L.sub.3 *R.sub.5 = +2.52189 T.sub.3 = .3197 1.592 30.4 *R.sub.6 = -1.72278 S.sub.3 = .8906 L.sub.4 R.sub.7 = -55.9411 MIRROR STOP S.sub.4 = .8966 L.sub.3R *R.sub.8 = -1.72278 T.sub.4 = .3197 1.592 30.4 *R.sub.9 = + 2.52189 S.sub.5 = .0100 L.sub.2R R.sub.10 = -6.3260 T.sub.5 = .4046 1.522 59.5 R.sub.11 = +2.3490 S.sub.6 = 13.3206 BFL ______________________________________
• wherein the first column lists the lens elements numerically, the second column lists the respective radii and vertex radii of the aspheric surfaces *R.sub.5, *R.sub.6, *R.sub.7, and *R.sub.8 of the elements, using the convention that convex surfaces have positive radii and concave surfaces have negative radii, the third column lists the respective thickness of the elements, the fourth column lists the axial spacings between adjacent elements and the film plane, and the fifth and sixth columns list respectively the refractive and dispersive indices of the optical materials of the lens system.