Ultra wide-angle eyepiece

Claim 2

An ultra wide-angle eyepiece having six lens elements in the positive power group arranged in a 2-1-2-1 format and two lens elements in the negative power group with the internal focal plane of the eyepiece lying between the two groups in which the lens surface of the positive group closest to the internal focal plane is convex or plano, said lens elements for a 10 mm. focal length eyepiece having parameters substantially as set forth in the following table wherein lens curvatures, lens thicknesses, and lens separations are given in millimeters, and N is the refractive index and V is the Abbe number of the glass used for a lens element: ______________________________________ Lens Radius Thickness Aperture Glass N V ______________________________________ r1=-18.56 L1 t1=1.65 8.24 SF5 1.6727 32.2 r2=+44.30 L2 t2=7.83 12.36 SK16 1.6204 60.3 r3=-18.56 s1=0.41 r4=plano L3 t3=4.53 15.66 SK16 1.6204 60.3 r5=-44.30 s2=0.41 r6=+82.40 L4 t4=14.01 17.30 SK16 1.6204 60.3 r7=-20.59 L5 t5=2.47 19.77 SF1 1.7174 29.5 r8=-82.40 s3=0.41 r9=+40.14 L6 t6=9.06 19.77 SK16 1.6204 60.3 r10=-82.40 s4=36.26 r11=-20.59 L7 t7=2.06 9.89 LAK8 1.7130 53.8 r12=+15.57 L8 t8=4.94 10.71 SF1 1.7174 29.5 r13=+168.59 ______________________________________

Claim 3

An ultra wide-angle eyepiece having six lens elements in the positive power group arranged in a 2-1-2-1 format and two lens elements in the negative power group with the internal focal plane of the eyepiece lying between the two groups in which the lens surface of the positive group closest to the internal focal plane is convex or plano, said lens elements for a 10 mm. focal length eyepiece having parameters substantially as set forth in the following table wherein lens curvatures, lens thicknesses, and lens separations are given in millimeters, and N is the refractive index and V is the Abbe number of the glass used for a lens element: ______________________________________ Ap- er- Lens Radius Thickness ture Glass N V ______________________________________ r1 = -12.94 L1 t1 = 0.94 5.46 SF5 1.6727 32.2 r2 = +17.67 L2 t2 = 6.38 9.10 SK16 1.6204 60.3 r3 = -12.94 s1 = 0.44 r4 = -58.39 L3 t3 = 3.63 11.38 SK16 1.6204 60.3 r5 = -22.15 s2 = 0.44 r6 = +73.57 L4 t4 = 9.57 13.65 SK16 1.6204 60.3 r7 = -17.67 L5 t5 = 1.38 13.65 SF1 1.7174 29.5 r8 = -58.39 s3 = 0.44 r9 = +27.95 L6 t6 = 6.82 15.02 SK16 1.6204 60.3 r10 = -73.57 s4 = 22.84 r11 = -14.09 L7 t7 = 1.88 6.83 LAF21 1.7883 47.4 r12 = +33.63 L8 t8 = 6.88 9.10 SF4 1.7552 27.6 r13 = -46.46 ______________________________________

Claim 4

An ultra wide-angle eyepiece having six lens elements in the positive power group arranged in a 2-1-2-1 format and two lens elements in the negative power group with the internal focal plane of the eyepiece lying between the two groups in which the lens surface of the positive group closest to the internal focal plane is convex or plano, said lens elements for a 10 mm. focal length eyepiece having parameters substantially as set forth in the following table wherein lens curvatures, lens thicknesses, and lens separations are given in millimeters, and N is the refractive index and V is the Abbe number of the glass used for a lens element: ______________________________________ Ap- er- Lens Radius Thickness ture Glass N V ______________________________________ r1 = -12.94 L1 t1 = 0.94 5.46 SF5 1.6727 32.2 r2 = +17.67 L2 t2 = 6.38 9.10 SK16 1.6204 60.3 r3 = -12.94 s1 = 0.44 r4 = -58.39 L3 t3 = 3.63 11.38 SK16 1.6204 60.3 r5 = -22.15 s2 = 0.44 r6 = +73.57 L4 t4 = 9.57 13.65 SK16 1.6204 60.3 r7 = -17.67 L5 t5 = 1.38 13.65 SF1 1.7174 29.5 r8 = -58.39 s3 = 0.44 r9 = +27.95 L6 t6 = 6.82 15.02 SK16 1.6204 60.3 r10 = -73.57 s4 = 22.84 r11 = -14.09 L7 t7 = 1.88 6.83 LAF21 1.7883 47.4 r12 = +33.63 L8 t8 = 6.88 9.10 SF4 1.7552 27.6 r13 = -46.46 ______________________________________

Claim 5

An ultra wide-angle eyepiece having six lens elements in the positive power group arranged in a 2-1-1-2 format and two lens elements in the negative power group with the internal focal plane of the eyepiece lying between the two groups in which the lens surface of the positive group closest to the internal focal plane is convex or plano, said lens elements for a 10 mm. focal length eyepiece having parameters substantially as set forth in the following table wherein lens curvatures, lens thicknesses, and lens separations are given in millimeters, and N is the refractive index and V is the Abbe number of the glass used for a lens element: ______________________________________ Ap- er- Lens Radius Thickness ture Glass N V ______________________________________ r1 = -24.25 L1 t1 = 1.89 9.33 SF1 1.7174 29.5 r2 = +44.45 L2 t2 = 9.25 13.33 SK16 1.6204 60.3 r3 = -19.99 s1 = 0.16 r4 = +130.93 L3 t3 = 5.43 20.00 SK16 1.6204 60.3 r5 = -69.51 s2 = 0.16 r6 = +48.50 L4 t4 = 8.15 20.00 SK16 1.6204 60.3 r7 = -146.71 s3 = 0.16 r8 = +88.33 L5 t5 = 11.28 20.00 SK16 1.6204 60.3 r9 = -32.88 L6 t6 = 2.35 20.00 SF1 1.7174 29.5 r10 = -103.48 s4 = 39.83 r11 = -20.64 L7 t7 = 1.59 9.33 LAK8 1.7130 53.8 r12 = +17.52 L8 t8 = 4.25 9.33 SF1 1.7174 29.5 r13 = + 1144.93 ______________________________________

Claim 6

An ultra wide-angle eyepiece having six lens elements in the positive power group arranged in a 2-1-1-2 format and two lens elements in the negative power group with the internal focal plane of the eyepiece lying between the two groups in which the lens surface of the positive group closest to the internal focal plane is convex or plano, said lens elements for a 10 mm. focal length eyepiece having parameters substantially as set forth in the following table wherein lens curvatures, lens thicknesses, and lens separations are given in millimeters, and N is the refractive index and V is the Abbe number of the glass used for a lens element: ______________________________________ Ap- er- Lens Radius Thickness ture Glass N V ______________________________________ r1 = -24.25 L1 t1 = 1.89 9.33 SF1 1.7174 29.5 r2 = +44.45 L2 t2 = 9.25 13.33 SK16 1.6204 60.3 r3 = -19.99 s1 = 0.16 r4 = +130.93 L3 t3 = 5.43 20.00 SK16 1.6204 60.3 r5 = -69.51 s2 = 0.16 r6 = +48.50 L4 t4 = 8.15 20.00 SK16 1.6204 60.3 r7 = -146.71 s3 = 0.16 r8 = +88.33 L5 t5 = 11.28 20.00 SK16 1.6204 60.3 r9 = -32.88 L6 t6 = 2.35 20.00 SF1 1.7174 29.5 r10 = -103.48 s4 = 39.83 r11 = -20.64 L7 t7 = 1.59 9.33 LAK8 1.7130 53.8 r12 = +17.52 L8 t8 = 4.25 9.33 SF1 1.7174 29.5 r13 = + 1144.93 ______________________________________

Claim 7

An ultra wide-angle eyepiece having six lens elements in the positive power group arranged in a 2-1-2-1 format and two lens elements in the negative power group with the internal focal plane of the eyepiece lying between the two groups in which the lens surface of the positive group closest to the internal focal plane is convex or plano, said lens elements for a 10 mm. focal length eyepiece having parameters substantially as set forth in the following table wherein lens curvatures, lens thicknesses, and lens separations are given in millimeters, and N is the refractive index and V is the Abbe number of the glass used for a lens element: ______________________________________ Ap- er- Lens Radius Thickness ture Glass N V ______________________________________ r1 = -10.23 L1 t1 = 0.79 4.75 SF5 1.6727 32.2 r2 = +14.02 L2 t2 = 5.94 7.53 SK16 1.6204 60.3 r3 = -10.23 s1 = 0.28 r4 = -46.05 L3 t3 = 2.77 9.51 SK16 1.6204 60.3 r5 = -17.62 s2 = 0.28 r6 = +59.09 L4 t4 = 7.13 10.89 SK16 1.6204 60.3 r7 = -14.02 L5 t5 = 1.19 10.89 SF1 1.7174 29.5 r8 = -46.05 s3 = 0.28 r9 = +22.31 L6 t6 = 5.94 12.28 SK16 1.6204 60.3 r10 = -59.09 s4 = 19.03 r11 = -7.61 L7 t7 = 1.98 5.15 LAF2 1.7440 44.9 r12 = +56.61 s5 = 6.93 r13 = -82.46 L8 t8 = 4.36 9.31 FK5 1.4875 70.4 r14 = -12.63 ______________________________________

Claim 8

An ultra wide-angle eyepiece having six lens elements in the positive power group arranged in a 2-1-2-1 format and two lens elements in the negative power group with the internal focal plane of the eyepiece lying between the two groups in which the lens surface of the positive group closest to the internal focal plane is convex or plano, said lens elements for a 10 mm. focal length eyepiece having parameters substantially as set forth in the following table wherein lens curvatures, lens thicknesses, and lens separations are given in millimeters, and N is the refractive index and V is the Abbe number of the glass used for a lens element: ______________________________________ Ap- er- Lens Radius Thickness ture Glass N V ______________________________________ r1 = -10.23 L1 t1 = 0.79 4.75 SF5 1.6727 32.2 r2 = +14.02 L2 t2 = 5.94 7.53 SK16 1.6204 60.3 r3 = -10.23 s1 = 0.28 r4 = -46.05 L3 t3 = 2.77 9.51 SK16 1.6204 60.3 r5 = -17.62 s2 = 0.28 r6 = +59.09 L4 t4 = 7.13 10.89 SK16 1.6204 60.3 r7 = -14.02 L5 t5 = 1.19 10.89 SF1 1.7174 29.5 r8 = -46.05 s3 = 0.28 r9 = +22.31 L6 t6 = 5.94 12.28 SK16 1.6204 60.3 r10 = -59.09 s4 = 19.03 r11 = -7.61 L7 t7 = 1.98 5.15 LAF2 1.7440 44.9 r12 = +56.61 s5 = 6.93 r13 = -82.46 L8 t8 = 4.36 9.31 FK5 1.4875 70.4 r14 = -12.63 ______________________________________