Scanning objective

Claim 2

A scanning objective characterized by two lens means with positive power of refraction, of which the first lens means, as viewed in the direction of incidence of the beam includes an aspherical surface which is so constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside and wherein the following values of curvatures φ 1 , φ 2 , φ 3 , and φ 4 of the lens surface and of the air spacing (l 2 ) of the two lens means as function of the intercept length s' with a focal distance f normalized to 1 ______________________________________ s'0.2 0.30.4 0.50.6 0.7 0.8 0.9 φ1 0.85 0.80.75 0.70.65 0.6 0.55 0.47 φ2 -0.25 -.012 -0.06 -0.04 -0.05 -0.04 0.04 0.35 φ3 1.15 1.11.0 0.80.6 0.35 0.27 0.25 φ4 -0.3 -0.2-0.22 -0.33 -0.5 -0.68 -0.85 -1.04 φ2 0.86 0.80.69 0.570.47 0.36 0.24 0.14 ______________________________________ whereby the tolerances of the curvatures and of the air spacing amount each to about ±0.25 (l 2 >0) and by the following values of the thickness l 1 of the first lens means: l 1 =0.35 with tolerances of +0.3 and 0.2 of the thickness l 3 of the second lens means: l 2 =0.25 with tolerances of +0.3 and -0.2, and of the indices of refraction n1, n3=1, 7±0.2.

Claim 3

A scanning objective according to claim 1, characterized in that an outer diameter of the first lens is reduced by about one-half, the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature ( surface distance measured in the direction of the optical axis) is reduced by more than a factor of 4, and in that this factor decreases from the outside toward the inside.

Claim 4

A scanning objective according to claim 2, characterized in that the factor by which the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature is reduced lies for a space between an edge and half-diameter of the first lens between about 8 and 80 and for a space between a half and quarter diameter of the first lens between 5 and 50.

Claim 5

A scanning objective according to claim 3, characterized by the following values for the relative deviation Δz of the aspherical surface from a spherical surface with the same vertex radius of curvature: ______________________________________ h 0.1 0.2 0.3 0.4 0.5 0.6 Δz 0.005 0.03 0.11 0.4 1.0 2.2 ______________________________________ whereby the focal distance f as well as the relative deviation Δz ( surface distance measured in the direction of the optical axis) is normalized to 1 with a distance h from the optical axis of 0.5.

Claim 6

A scanning objective according to claim 4, characterized in that the first surface of the first lens means is the aspherical surface.

Claim 7

A scanning objective according to claim 5, characterized in that the first lens means has a second aspherical surface, of which at least one of said first and second aspherical surfaces of said first lens is so constructed that in comparison with a spherical surface having the same vertex radius of curvature, the thickness of the lens means increases toward the outside.

Claim 8

A scanning objective according to claim 6, characterized in that the objective has the data of one of the four following embodiments: ______________________________________ R1 R2 R3 R4 l1 l2 l3 s' n1 n3 ______________________________________ 11.97 1048.1 9.52 -46.56 3.5 7.4 2.5 3.9 1.61 1.79 9.64 29.41 12.5 -28.51 3.5 5. 2.5 5.19 1.61 1.79 7.07 12.12 15.87 -22.22 3.5 2.8 2.5 5.77 1.61 1.79 10.32 145.09 9.09 -60.43 3.5 7.4 2.5 5.82 1.61 1.79 ______________________________________ as- pheric sur- face R K AC4 AC6 AC8 AC10 ______________________________________ 1 -0.001 0 0 0 0 2 0 0.18 E-3 -0.9375 E-05 0.399 E-07 0 1 0.026 0 0 0 0 2 0 0.30 E-3 0.1800 E-05 0.313 E-07 0 1 -0.169 0 0 0 0 2 0 0.50 E-3 0.5970 E-05 0.143 E-06 0 1 -0.00286 0 0 0 0 2 0 0.26 E-3 0.5400 E-06 0.143 E-07 0 4 0 0.2 E-3 0 0 0 ______________________________________ wherein R equals the radius of curvature of the lens surface with the numerals thereafter denoting which surface in said direction of incidence; l indicating the spacing between lens surfaces along a center line in said direction of incidences with the numeral 1 being the distance between the first and second lens surface, numeral 2 between the second and third lens surfaces, and numeral 3 between the third and fourth lens surface; s' being the intercept length; n is the index of refraction of the lens material with the numeral 1 designating the lens material between lens surfaces 1 and 2, and numeral 3 designating the lens material between lens surfaces 3 and 4; and wherein K, AC4, AC6, AC8 and AC10 are aspherical coefficients used to determine a meniscus height of an aspherical surface represented by the follwing equation wherein ##EQU2## and wherein h is a distance of a surface point from an optical axis and φ is a surface vertex.

Claim 9

A scanning objective characterized by two lens means with positive power of refraction, of which the first lens means, as viewed in the direction of incidence of the beam includes an aspherical surface which is so constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside and wherein an outer diameter of the first lens is reduced by about one-half, the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature (surface distance measured in the direction of the optical axis) is reduced by more than a factor of 4, and in that this factor decreases from the outside toward the inside.

Claim 10

A scanning objective characterized by two lens means with positive power of refraction, of which the first lens means, as viewed in the direction of incidence of the beam includes an aspherical surface which is so constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside and wherein an outer diameter of the first lens is reduced by about one-half, the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature (surface distance measured in the direction of the optical axis) is reduced by more than a factor of 4, and in that this factor decreases from the outside toward the inside.

Claim 11

A scanning objective according to claim 8, characterized in that the factor by which the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature is reduced lies for a space between an edge and half-diameter of the first lens between about 8 and 80 and for a space between half and quarter diameter of the first lens between 5 and 50.

Claim 12

A scanning objective according to claim 9, characterized by the following values for the relative deviation Δz of the aspherical surface from a spherical surface with the same vertex radius of curvature: ______________________________________ h 0.1 0.2 0.3 0.4 0.5 0.6 Δz 0.005 0.03 0.11 0.4 1.0 2.2 ______________________________________ whereby the focal distance f as well as the relative deviation Δz ( surface distance measured in the direction of the optical axis) is normalized to 1 with a distance h from the optical axis of 0.5.

Claim 13

A scanning objective characterized by two lens means with positive power of refraction, of which the first lens means, as viewed in the direction of incidence of the beam includes an aspherical surface which is so constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside and wherein the first surface of the first lens means is the aspherical surface and wherein the first lens means has a second aspherical surface, of which at least one of said first and second aspherical surface of said first lens is so constructed that in comparison with a spherical surface having the same vertex of curvature, the thickness of the lens means increases toward the outside.

Claim 14

A scanning objective characterized by two lens means with positive power of refraction, of which the first lens means, as viewed in the direction of incidence of the beam includes an aspherical surface which is so constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside and wherein the first surface of the first lens means is the aspherical surface and wherein the first lens means has a second aspherical surface, of which at least one of said first and second aspherical surface of said first lens is so constructed that in comparison with a spherical surface having the same vertex of curvature, the thickness of the lens means increases toward the outside.

Claim 15

A scanning objective characterized by two lens means with positive power of refraction, of which the first lens means, as viewed in the direction of incidence of the beam includes an aspherical surface which is to constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside and wherein the objective has the data of one of the embodiments according to the following Tables 1-3, TABLE 1 __________________________________________________________________________ aspher surface Example R1 R2 R3 R4 l1 l2 l3 s' n1 n3 R __________________________________________________________________________ 1 12.82 -335.05 9.52 -206.94 3.5 7.28 4.0 4.0 1.51 1.89 1 2 12.82 -61.57 9.52 -50.66 3.5 7.94 1.0 4.0 1.61 1.79 1 3 12.2 -419.27 9.52 -55.87 1.5 8.25 2.5 4.0 1.61 1.78 1 4 11.49 -42.56 9.52 -24.30 3.5 6.48 2.5 4.0 1.51 1.61 1 5 14.29 410.64 11.76 -46.65 3.5 7.04 2.5 4.0 1.78 1.89 1 6 13.89 -65.76 11.76 -41.99 3.5 7.4 2.5 4.0 1.61 1.89 1 7 11.76 51.12 6.9 29.92 3.5 8.31 2.5 4.0 1.61 1.89 1 8 12.82 -178.88 9.52 -58.61 3.5 7.27 2.5 4.0 1.61 1.79 1 9 17.09 -51.18 66.67 -12.51 3.5 3.14 2.5 7.0 1.61 1.79 1 10 14.93 61.09 16.67 -18.49 3.5 3.57 2.5 7.0 1.61 1.79 1 11 17.24 -99.39 28.57 -17.24 3.5 4.66 1.0 7.0 1.61 1.89 1 12 17.24 -272.17 28.57 -16.35 1.5 4.99 2.5 7.0 1.61 1.89 1 13 16.67 -63.99 28.57 -16.72 3.5 3.85 2.5 7.0 1.51 1.89 1 14 13.51 -57.53 28.57 -11.13 3.5 2.49 2.5 7.0 1.51 1.60 1 15 16.67 -165.71 28.57 -14.44 3.5 3.41 2.5 7.0 1.61 1.79 1 16 8.33 22.65 12.5 -39.13 3.5 4.32 2.5 5 1.61 1.79 2 17 9.70 26.73 10.0 -54.65 3.5 5.49 2.5 5 1.61 1.79 2 18 9.71 53.47 12.5 -24.42 4.5 5.08 2.5 5.0 1.51 1.79 2 19 9.71 49.64 12.5 -49.7 3.5 6.10 1.0 5.0 1.61 1.89 2 20 9.71 34.59 12.5 -29.75 3.5 5.15 2.5 5.0 1.61 1.79 2 21 11.97 1048.1 9.52 -46.56 3.5 7.4 2.5 3.9 1.61 1.79 1 2 22 9.64 29.41 12.5 -28.51 3.5 5. 2.5 5.19 1.61 1.79 1 2 23 7.07 12.12 15.87 -22.22 3.5 2.8 2.5 5.77 1.61 1.79 1 2 __________________________________________________________________________ Example K AC4 AC6 AC8 AC10 __________________________________________________________________________ 1 -1.817 0 -0.7964 E-06 0 0 2 -2.104 0 -0.926 E-06 0 0 3 -1.594 0 -0.742 E-06 0 0 4 -2.033 0 -0.137 E-05 0 0 5 -1.912 0 -0.620 E-06 0 0 6 -2.550 0 -0.997 E-06 0 0 7 -0.937 0 -0.338 E-06 0 0 8 -1.796 0 -0.766 E-06 0 0 9 -0.911 -0.3 E-3 -0.269 E-05 -0.709 E-07 0 10 1.801 -0.30 E-3 -0.247 E-05 -0.464 E-07 0 11 1.688 -0.30 E-3 -0.2155 E-05 -0.417 E-07 0 12 1.505 -0.30 E-3 -0.2256 E-05 -0.456 E-07 0 13 0.518 -0.30 E-3 -0.228 E-05 -0.476 E-07 0 14 -1.799 -0.30 E-3 -0.445 E.05 -0.286 E-07 -0.200 E-08 15 0.977 -0.30 E-3 -0.309 E-05 -0.400 E-07 0 16 4.922 0.30 E-3 0.176 E.05 0.39 E.07 0 17 -7.96 0.30 E-3 0.12 E-5 0.218 E-7 0 18 98.434 0.30 E-3 0.73 E-6 -0.224 E-7 0 19 -30.32 0.30 E-3 0.567 E-6 0.195 E-7 0 20 -6.708 0.30 E-3 0.13 E-5 0.277 E-7 0 21 -0.001 0 0 0 0 0.18 E-3 -0.9375 E-05 0.399 E-07 0 22 0.026 0 0 0 0 0.30 E-3 0.18 E-05 0.313 E-07 0 23 -0.169 0 0 0 0 0.50 E-3 0.597 E-05 0.143 E-06 0 __________________________________________________________________________ TABLE 2 aspher surface Example R1 R2 R3 R4 l1 l2 l3 s' n1 n3 R K AC4 AC6 AC8 AC10 1 12.82 -30.85 9.52 -64.06 3.5 7.9 2.5 5.0 1.61 1.79 1 0 -0.17 E-3 -0.155 E-6 -0.97 E-8 0 3 0 -0.11 E-3 0.665 E-6 0 0 2 12.82 -27.92 9.52 -26.15 3.5 8.32 2.5 8.0 1.61 1.79 1 0 -0.137 E-3 -0.635 E-6 -0.202 E-7 0 3 0 -0.236 E-3 -0.168 E-5 0 0 3 12.82 -51.2 9.52 -49.25 5.0 6.79 4.0 5.0 1.61 1.79 1 0 -0.136 E-3 -0.104 E-6 -0.106 E-7 0 3 0 -0.133 E-3 -0.103 E-5 0 0 4 12.82 -28.07 9.52 -42.23 1.5 9.23 1.5 5.0 1.61 1.79 1 0 -0.196 E-3 -0.100 E-6 -0.997 E-8 0 3 0 -0.14 E-3 -0.315 E-7 0 0 5 20.00 -13.64 25.0 -11.9 3.5 7.92 2.5 5.0 1.61 1.79 1 0 -0.3 E-3 -0.227 E-6 -0.113 E-7 0 3 0 -0.293 E-3 -0.163 E-5 0 0 6 12.82 -90.1 6.67 -399.43 3.5 9.56 2.5 5.0 1.61 1.79 1 0 -0.132 E-3 0.309 E-6 -0.213 E-7 0 3 0 -0.24 E-3 -0.673 E-5 0 0 7 8.33 1008.7 9.52 38.34 3.5 6.17 2.5 5.0 1.61 1.79 1 0 -0.18 E-3 -0.10 E-5 -0.305 E-7 0 3 0 -0.27 E-3 -0.23 E-5 0 0 8 50.0 -12.83 9.52 -18.45 3.5 10.33 2.5 5.0 1.61 1.79 1 0 -0.27 E-3 0.65 E-7 -0.20 E-7 0 3 0 -0.237 E-3 -0.603 E-5 0 0 9 12.5 -98.95 9.52 -52.28 3.5 7.57 2.5 3.5 1.61 1.79 1 0 -0.115 E-3 -0.432 E-6 -0.877 E-8 0 3 0 0.974 E-5 -0.50 E-6 0 0 10 20.0 -13.96 9.52 -20.26 3.5 9.24 2.5 4. 1.61 1.79 1 0 -0.27 E-3 0.116 E-6 -0.113 E-7 0 3 0 -0.186 E-3 -0.433 E-5 0 0 11 12.82 -270.55 9.52 493.87 3.5 7.7 2.5 5.0 1.79 1.89 1 0 -0.101 E-3 -0.112 E-6 -0.725 E-8 0 3 0 -0.113 E-3 0.587 E-6 0 0 12 12.82 -16.01 9.52 -13.04 3.5 7.39 2.5 5.0 1.51 1.51 1 0 -0.28 E-3 -0.529 E-6 -0.124 E-7 0 3 0 -0.325 E-3 -0.287 E-5 0 0 13 12.82 -30.85 9.52 -64.05 3.5 7.9 2.5 5.0 1.61 1.79 1 0 -0.17 E-3 -0.155 E-6 -0.972 E-8 0 3 0 -0.113 E-3 0.666 E-6 0 0 14 12.82 -20.67 9.52 -43.78 3.5 8.32 2.5 4.0 1.61 1.79 1 0 -0.223 E-3 -0.778 E-7 -0.832 E-8 0 4 0 0.175 E-3 -0.793 E-5 0 0 15 8.33 15.44 7.69 27.97 3.5 5.94 2.5 6.0 1.79 1.89 1 0 -0.13 E-3 -0.499 E-6 -0.245 E-7 0 4 0 0.46 E-3 0.14 E-5 0 0 16 50.00 -15.77 9.52 -25.22 3.5 10.1 2.5 6.0 1.61 1.79 1 0 -0.219 E-3 0.247 E-6 -0.112 E-7 0 4 0 0.25 E-3 -0.15 E-5 0 0 17 25.00 -42.63 9.52 -49.87 3.5 9.43 2.5 6.0 1.79 1.89 1 0 -0.112 E-3 0.184 E-6 -0.80 E-8 0 4 0 0.19 E-3 -0.14 E-5 0 0 18 20.00 -13.59 11.11 -10.72 3.5 7.44 2.5 6.0 1.51 1.51 1 0 -0.339 E-3 -0.119 E-6 -0.14 E-7 0 4 0 0.434 E-3 -0.319 E-5 0 0 19 12.82 -199.77 9.52 -54.97 3.5 7.33 2.5 4.0 1.61 1.79 1 0 -0.114 E-3 -0.441 E-6 -0.937 E-8 0 4 0 0.773 E-5 0.695 E-6 0 0 20 20.00 -22.32 11.11 -26.51 3.5 8.26 2.5 6.0 1.61 1.79 1 0 -0.19 E-3 0.178 E-6 -0.12 E-7 0 4 0 0.179 E-3 -0.178 E-5 0 0 21 9.09 14.15 12.5 -21.4 3.5 4.0 2.5 8.78 1.61 1.79 1 0.12212 -0.25 E-3 -0.727 E-6 -0.46 E-7 0 4 3.12615 0.26 E-3 -0.2 E-5 0 0 22 10.00 76.69 9.09 -68.03 3.5 7.16 2.5 6.00 1.61 1.79 2 0 0.264 E-3 -0.377 E-6 0.122 E-7 0 4 0 0.217 E-3 -0.559 E-6 0 0 23 8.33 430.61 7.14 27.95 3.5 7.65 2.5 4.00 1.61 1.79 2 0 0.349 E-3 -0.874 E-6 0.17 E-7 0 4 0 0.270 E-3 0.554 E-4 0 0 24 10.00 23.03 9.09 -54.17 3.5 6.34 2.5 5.0 1.61 1.79 2 0 0.234 E-3 0.59 E-6 0.34 E-7 0 4 0 0.77 E-4 -0.24 E-6 0 0 25 10.32 145.69 9.09 -60.43 3.5 7.4 2.5 5.82 1.61 1.79 1 -0.00286 0 0 0 0 2 0 0.26 E-3 -0.54 E-6 0.143 E-7 0 4 0 0.2 E-3 0 0 0 26 9.43 23.52 9.09 -35.01 5.0 5.62 4.0 6.0 1.61 1.79 2 0 0.379 E-3 0.929 E-6 0.419 E-7 0 4 0 0.286 E-3 -0.182 E-5 0 0 27 9.43 367.44 9.09 542.83 1.5 8.08 1.5 6.0 1.61 1.79 2 0 0.214 E-3 -0.807 E-6 0.678 E-8 0 4 0 0.215 E-3 0.152 E-5 0 0 28 9.43 -414.55 7.14 -19.9 3.5 6.77 2.5 6.0 1.51 1.51 2 0 0.33 E-3 -0.667 E-6 0.105 E-7 0 4 0 0.54 E-3 -0.306 E-5 0 0 29 12.5 68.56 6.67 -194.68 3.5 10.05 2.5 6.0 1.61 1.79 2 0 0.182 E-3 -0.122 E-5 0.185 E-7 0 4 0 0.519 E-3 -0.445 E-5 0 0 30 8.33 31.4 9.09 -284.31 3.5 6.27 2.5 6.0 1.61 1.79 2 0 0.349 E-3 0.687 E-7 0.224 E-7 0 4 0 0.246 E-3 0.323 E-5 0 0 31 50.00 -17.32 9.09 -21.92 3.5 10.88 2.5 6.0 1.61 1.79 2 0 0.204 E-3 0.113 E-6 0.561 E-8 0 4 0 0.335 E-3 -0.197 E-5 0 0 32 10.00 76.69 9.09 -68.03 3.5 7.16 2.5 6.0 1.61 1.79 2 0 0.264 E-3 -0.377 E-6 0.122 E-7 0 4 0 0.217 E-3 -0.56 E-6 0 0 33 20.00 -43.51 20.0 -14.05 3.5 6.66 2.5 8.0 1.61 1.79 2 0 0.295 E-3 0.680 E-6 0.288 E-7 0 4 0 0.141 E-3 -0.339 E-6 0 0 34 8.7 28.09 9.09 -177.9 3.5 6.07 2.5 4.0 1.61 1.79 2 0 0.264 E-3 -0.24 E-6 0.388 E-7 -0.2 E-9 3 0 -0.293 E-4 -0.442 E-5 0 0 35 9.43 -55.23 9.09 -90.43 3.5 7.78 2.5 4.0 1.61 1.79 2 0 0.322 E-3 -0.177 E-5 0.25 E-7 -0.1 E-9 3 0 -0.910 E-4 -0.153 E-7 0 0 36 14.29 82.09 10.0 -28.32 1.5 9.63 1.5 8.0 1.61 1.79 2 0 0.170 E-3 0.423 E-6 0.161 E-7 0 3 0 -0.192 E-3 -0.149 E-5 0 0 37 11.11 -141.85 9.09 -71.37 1.5 8.87 1.5 6.0 1.61 1.79 2 0 0.19 E-3 -0.635 E-6 0.1 E-7 0 3 0 -0.148 E-3 -0.341 E-5 0 0 38 8.33 89.51 16.67 -26.6 3.5 5.48 2.5 6.0 1.61 1.79 2 0 0.348 E-3 -0.111 E-5 0.328 E-7 -0.3 E-9 3 0 -0.17 E-3 -0.635 E-5 0 0 39 20.00 -34.29 9.09 -23.23 3.5 9.87 2.5 6.0 1.61 1.79 2 0 0.178 E-3 0.134 E-6 0.209 E-7 0 3 0 -0.221 E-3 -0.397 E-5 0 0 40 9.43 25.15 11.11 -82.02 3.5 6.21 2.5 6.0 1.79 1.89 2 0 0.236 E-3 -0.452 E-8 0.178 E-7 0 3 0 -0.14 E-3 -0.238 E-5 0 0 41 9.43 -33.61 9.09 -12.56 3.5 7.06 2.5 5.0 1.51 1.51 2 0 0.387 E-3 -0.15 E-5 0.27 E-7 0 3 0 -0.349 E-3 -0.185 E-4 0 0 42 9.43 46.17 9.09 -55.72 3.5 7.15 2.5 6.0 1.61 1.79 2 0 0.276 E-3 -0.123 E-6 0.223 E-7 0 3 0 -0.161 E-3 -0.342 E-5 0 0 TABLE 3 __________________________________________________________________________ Example 1 2 3 4 5 6 __________________________________________________________________________ R1 22.19 20.00 19.23 20.00 33.33 20.83 R2 -16.39 -27.10 -20.61 -18.09 -11.61 -16.82 R3 16.67 16.67 16.67 12.5 100.00 16.67 R4 -22.0 -18.57 -17.17 -61.03 -13.15 -17.07 R5 12.5 12.5 8.33 12.5 12.5 12.5 R6 -88.05 45.56 21.47 -39.96 -39.96 61.08 l1 3.5 3.5 3.5 3.5 3.5 3.5 l2 7.4 6.14 7.72 7.38 7.3 7.27 l3 2.5 2.5 2.5 2.5 2.5 2.5 l4 0.2 0.2 0.2 0.2 0.2 0.2 l5 2.0 2.0 2.0 2.0 2.0 2.0 s' 4.57 6.0 4.5 4.5 4.5 4.5 n1 1.61 1.61 1.61 1.61 1.61 1.61 n3 1.51 1.51 1.51 1.51 1.51 1.51 n5 1.51 1.51 1.51 1.51 1.51 1.51 aspher. 1 1 1 1 1 1 surface R K -20.318 -20.0 -20.0 -20.0 -20.0 -20.0 AC4 0 0.116 E-3 0.15 E-3 0.11 E-3 -0.284 E-3 0.461 E-3 AC6 -0.359 E-5 -0.545 E-5 - 0.679 E-5 -0.61 E-5 -0.706 E-6 -0.511 E-5 AC8 0.33 E-7 0.485 E-7 0.769 E-7 0.76 E-7 -0.397 E-8 0.569 E-7 AC10 0 0 0 0 0 0 __________________________________________________________________________ Example 7 8 9 10 11 12 __________________________________________________________________________ R1 28.46 20.46 28.46 16.13 16.67 20.00 R2 -16.98 -14.17 -35.61 195.38 -35.03 -13.77 R3 16.67 16.67 16.67 16.67 16.67 16.67 R4 -19.72 -23.48 -46.27 -15.05 -21.4 -406.33 R5 12.5 12.5 12.5 12.5 12.50 10.0 R6 327.48 -39.96 38.95 41.36 -62.16 -18.38 l1 5.0 3.5 3.5 3.5 3.5 3.5 l2 5.93 7.76 8.8 4.79 6.91 7.44 l3 4.0 2.5 2.5 2.5 2.5 2.5 l4 0.2 0.2 0.2 0.2 0.2 0.2 l5 3.0 2.0 2.0 2.0 2.0 2.0 s' 4.5 4.5 4.5 5.0 3.0 3.7 n1 1.61 1.61 1.79 1.61 1.61 1.61 n3 1.51 1.51 1.79 1.51 1.51 1.51 n5 1.51 1.51 1.79 1.51 1.51 1.51 aspher. 1 1 1 1 1 1 surface R K -20.0 - 20.0 -20.0 0 0 -20.0 AC4 -0.101 E-3 -0.149 E-3 -0.218 E-3 -0.169 E-3 -0.135 E-3 0.428 E-3 AC6 -0.119 E-5 -0.107 E-5 -0.108 E-5 -0.11 E-5 -0.418 E-6 -0.619 E-5 AC8 0.249 E-9 0.669 E-9 0.314 E-8 -0.215 E-7 -0.685 E-8 0.8 E-7 AC10 0 0 0 0 0 0 __________________________________________________________________________ E-3 means 10.sup.-3 wherein R equals the radius of curvature of the lens surface with the numerals thereafter denoting which surface in said direction of incidence; l indicating the spacing between lens surfaces along a center line in said direction of incidences with the numeral 1 being the distance between the first and second lens surface, numeral 2 between the second and third lens surfaces, and numeral 3 between the third and fourth lens surface; s' being the intercept length; n is the index of refraction of the lens material with the numeral 1 designating the lens material between lens surfaces 1 and 2, and numeral 3 designating the lens material between lens surfaces 3 and 4; and wherein K, AC4, AC6, AC8 and AC10 are spherical coefficients used to determine a meniscus height of an aspherical surface represented by the following equation wherein ##EQU3## and wherein h is a distance of a surface point from an optical axis and is φ a surface vertex.

Claim 16

A scanning objective characterized by two lens means with positive power of refraction, of which the first lens means, as viewed in the direction of incidence of the beam includes an aspherical surface which is to constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside and wherein the objective has the data of one of the embodiments according to the following Tables 1-3, TABLE 1 __________________________________________________________________________ aspher surface Example R1 R2 R3 R4 l1 l2 l3 s' n1 n3 R __________________________________________________________________________ 1 12.82 -335.05 9.52 -206.94 3.5 7.28 4.0 4.0 1.51 1.89 1 2 12.82 -61.57 9.52 -50.66 3.5 7.94 1.0 4.0 1.61 1.79 1 3 12.2 -419.27 9.52 -55.87 1.5 8.25 2.5 4.0 1.61 1.78 1 4 11.49 -42.56 9.52 -24.30 3.5 6.48 2.5 4.0 1.51 1.61 1 5 14.29 410.64 11.76 -46.65 3.5 7.04 2.5 4.0 1.78 1.89 1 6 13.89 -65.76 11.76 -41.99 3.5 7.4 2.5 4.0 1.61 1.89 1 7 11.76 51.12 6.9 29.92 3.5 8.31 2.5 4.0 1.61 1.89 1 8 12.82 -178.88 9.52 -58.61 3.5 7.27 2.5 4.0 1.61 1.79 1 9 17.09 -51.18 66.67 -12.51 3.5 3.14 2.5 7.0 1.61 1.79 1 10 14.93 61.09 16.67 -18.49 3.5 3.57 2.5 7.0 1.61 1.79 1 11 17.24 -99.39 28.57 -17.24 3.5 4.66 1.0 7.0 1.61 1.89 1 12 17.24 -272.17 28.57 -16.35 1.5 4.99 2.5 7.0 1.61 1.89 1 13 16.67 -63.99 28.57 -16.72 3.5 3.85 2.5 7.0 1.51 1.89 1 14 13.51 -57.53 28.57 -11.13 3.5 2.49 2.5 7.0 1.51 1.60 1 15 16.67 -165.71 28.57 -14.44 3.5 3.41 2.5 7.0 1.61 1.79 1 16 8.33 22.65 12.5 -39.13 3.5 4.32 2.5 5 1.61 1.79 2 17 9.70 26.73 10.0 -54.65 3.5 5.49 2.5 5 1.61 1.79 2 18 9.71 53.47 12.5 -24.42 4.5 5.08 2.5 5.0 1.51 1.79 2 19 9.71 49.64 12.5 -49.7 3.5 6.10 1.0 5.0 1.61 1.89 2 20 9.71 34.59 12.5 -29.75 3.5 5.15 2.5 5.0 1.61 1.79 2 21 11.97 1048.1 9.52 -46.56 3.5 7.4 2.5 3.9 1.61 1.79 1 2 22 9.64 29.41 12.5 -28.51 3.5 5. 2.5 5.19 1.61 1.79 1 2 23 7.07 12.12 15.87 -22.22 3.5 2.8 2.5 5.77 1.61 1.79 1 2 __________________________________________________________________________ Example K AC4 AC6 AC8 AC10 __________________________________________________________________________ 1 -1.817 0 -0.7964 E-06 0 0 2 -2.104 0 -0.926 E-06 0 0 3 -1.594 0 -0.742 E-06 0 0 4 -2.033 0 -0.137 E-05 0 0 5 -1.912 0 -0.620 E-06 0 0 6 -2.550 0 -0.997 E-06 0 0 7 -0.937 0 -0.338 E-06 0 0 8 -1.796 0 -0.766 E-06 0 0 9 -0.911 -0.3 E-3 -0.269 E-05 -0.709 E-07 0 10 1.801 -0.30 E-3 -0.247 E-05 -0.464 E-07 0 11 1.688 -0.30 E-3 -0.2155 E-05 -0.417 E-07 0 12 1.505 -0.30 E-3 -0.2256 E-05 -0.456 E-07 0 13 0.518 -0.30 E-3 -0.228 E-05 -0.476 E-07 0 14 -1.799 -0.30 E-3 -0.445 E.05 -0.286 E-07 -0.200 E-08 15 0.977 -0.30 E-3 -0.309 E-05 -0.400 E-07 0 16 4.922 0.30 E-3 0.176 E.05 0.39 E.07 0 17 -7.96 0.30 E-3 0.12 E-5 0.218 E-7 0 18 98.434 0.30 E-3 0.73 E-6 -0.224 E-7 0 19 -30.32 0.30 E-3 0.567 E-6 0.195 E-7 0 20 -6.708 0.30 E-3 0.13 E-5 0.277 E-7 0 21 -0.001 0 0 0 0 0.18 E-3 -0.9375 E-05 0.399 E-07 0 22 0.026 0 0 0 0 0.30 E-3 0.18 E-05 0.313 E-07 0 23 -0.169 0 0 0 0 0.50 E-3 0.597 E-05 0.143 E-06 0 __________________________________________________________________________ TABLE 2 aspher surface Example R1 R2 R3 R4 l1 l2 l3 s' n1 n3 R K AC4 AC6 AC8 AC10 1 12.82 -30.85 9.52 -64.06 3.5 7.9 2.5 5.0 1.61 1.79 1 0 -0.17 E-3 -0.155 E-6 -0.97 E-8 0 3 0 -0.11 E-3 0.665 E-6 0 0 2 12.82 -27.92 9.52 -26.15 3.5 8.32 2.5 8.0 1.61 1.79 1 0 -0.137 E-3 -0.635 E-6 -0.202 E-7 0 3 0 -0.236 E-3 -0.168 E-5 0 0 3 12.82 -51.2 9.52 -49.25 5.0 6.79 4.0 5.0 1.61 1.79 1 0 -0.136 E-3 -0.104 E-6 -0.106 E-7 0 3 0 -0.133 E-3 -0.103 E-5 0 0 4 12.82 -28.07 9.52 -42.23 1.5 9.23 1.5 5.0 1.61 1.79 1 0 -0.196 E-3 -0.100 E-6 -0.997 E-8 0 3 0 -0.14 E-3 -0.315 E-7 0 0 5 20.00 -13.64 25.0 -11.9 3.5 7.92 2.5 5.0 1.61 1.79 1 0 -0.3 E-3 -0.227 E-6 -0.113 E-7 0 3 0 -0.293 E-3 -0.163 E-5 0 0 6 12.82 -90.1 6.67 -399.43 3.5 9.56 2.5 5.0 1.61 1.79 1 0 -0.132 E-3 0.309 E-6 -0.213 E-7 0 3 0 -0.24 E-3 -0.673 E-5 0 0 7 8.33 1008.7 9.52 38.34 3.5 6.17 2.5 5.0 1.61 1.79 1 0 -0.18 E-3 -0.10 E-5 -0.305 E-7 0 3 0 -0.27 E-3 -0.23 E-5 0 0 8 50.0 -12.83 9.52 -18.45 3.5 10.33 2.5 5.0 1.61 1.79 1 0 -0.27 E-3 0.65 E-7 -0.20 E-7 0 3 0 -0.237 E-3 -0.603 E-5 0 0 9 12.5 -98.95 9.52 -52.28 3.5 7.57 2.5 3.5 1.61 1.79 1 0 -0.115 E-3 -0.432 E-6 -0.877 E-8 0 3 0 0.974 E-5 -0.50 E-6 0 0 10 20.0 -13.96 9.52 -20.26 3.5 9.24 2.5 4. 1.61 1.79 1 0 -0.27 E-3 0.116 E-6 -0.113 E-7 0 3 0 -0.186 E-3 -0.433 E-5 0 0 11 12.82 -270.55 9.52 493.87 3.5 7.7 2.5 5.0 1.79 1.89 1 0 -0.101 E-3 -0.112 E-6 -0.725 E-8 0 3 0 -0.113 E-3 0.587 E-6 0 0 12 12.82 -16.01 9.52 -13.04 3.5 7.39 2.5 5.0 1.51 1.51 1 0 -0.28 E-3 -0.529 E-6 -0.124 E-7 0 3 0 -0.325 E-3 -0.287 E-5 0 0 13 12.82 -30.85 9.52 -64.05 3.5 7.9 2.5 5.0 1.61 1.79 1 0 -0.17 E-3 -0.155 E-6 -0.972 E-8 0 3 0 -0.113 E-3 0.666 E-6 0 0 14 12.82 -20.67 9.52 -43.78 3.5 8.32 2.5 4.0 1.61 1.79 1 0 -0.223 E-3 -0.778 E-7 -0.832 E-8 0 4 0 0.175 E-3 -0.793 E-5 0 0 15 8.33 15.44 7.69 27.97 3.5 5.94 2.5 6.0 1.79 1.89 1 0 -0.13 E-3 -0.499 E-6 -0.245 E-7 0 4 0 0.46 E-3 0.14 E-5 0 0 16 50.00 -15.77 9.52 -25.22 3.5 10.1 2.5 6.0 1.61 1.79 1 0 -0.219 E-3 0.247 E-6 -0.112 E-7 0 4 0 0.25 E-3 -0.15 E-5 0 0 17 25.00 -42.63 9.52 -49.87 3.5 9.43 2.5 6.0 1.79 1.89 1 0 -0.112 E-3 0.184 E-6 -0.80 E-8 0 4 0 0.19 E-3 -0.14 E-5 0 0 18 20.00 -13.59 11.11 -10.72 3.5 7.44 2.5 6.0 1.51 1.51 1 0 -0.339 E-3 -0.119 E-6 -0.14 E-7 0 4 0 0.434 E-3 -0.319 E-5 0 0 19 12.82 -199.77 9.52 -54.97 3.5 7.33 2.5 4.0 1.61 1.79 1 0 -0.114 E-3 -0.441 E-6 -0.937 E-8 0 4 0 0.773 E-5 0.695 E-6 0 0 20 20.00 -22.32 11.11 -26.51 3.5 8.26 2.5 6.0 1.61 1.79 1 0 -0.19 E-3 0.178 E-6 -0.12 E-7 0 4 0 0.179 E-3 -0.178 E-5 0 0 21 9.09 14.15 12.5 -21.4 3.5 4.0 2.5 8.78 1.61 1.79 1 0.12212 -0.25 E-3 -0.727 E-6 -0.46 E-7 0 4 3.12615 0.26 E-3 -0.2 E-5 0 0 22 10.00 76.69 9.09 -68.03 3.5 7.16 2.5 6.00 1.61 1.79 2 0 0.264 E-3 -0.377 E-6 0.122 E-7 0 4 0 0.217 E-3 -0.559 E-6 0 0 23 8.33 430.61 7.14 27.95 3.5 7.65 2.5 4.00 1.61 1.79 2 0 0.349 E-3 -0.874 E-6 0.17 E-7 0 4 0 0.270 E-3 0.554 E-4 0 0 24 10.00 23.03 9.09 -54.17 3.5 6.34 2.5 5.0 1.61 1.79 2 0 0.234 E-3 0.59 E-6 0.34 E-7 0 4 0 0.77 E-4 -0.24 E-6 0 0 25 10.32 145.69 9.09 -60.43 3.5 7.4 2.5 5.82 1.61 1.79 1 -0.00286 0 0 0 0 2 0 0.26 E-3 -0.54 E-6 0.143 E-7 0 4 0 0.2 E-3 0 0 0 26 9.43 23.52 9.09 -35.01 5.0 5.62 4.0 6.0 1.61 1.79 2 0 0.379 E-3 0.929 E-6 0.419 E-7 0 4 0 0.286 E-3 -0.182 E-5 0 0 27 9.43 367.44 9.09 542.83 1.5 8.08 1.5 6.0 1.61 1.79 2 0 0.214 E-3 -0.807 E-6 0.678 E-8 0 4 0 0.215 E-3 0.152 E-5 0 0 28 9.43 -414.55 7.14 -19.9 3.5 6.77 2.5 6.0 1.51 1.51 2 0 0.33 E-3 -0.667 E-6 0.105 E-7 0 4 0 0.54 E-3 -0.306 E-5 0 0 29 12.5 68.56 6.67 -194.68 3.5 10.05 2.5 6.0 1.61 1.79 2 0 0.182 E-3 -0.122 E-5 0.185 E-7 0 4 0 0.519 E-3 -0.445 E-5 0 0 30 8.33 31.4 9.09 -284.31 3.5 6.27 2.5 6.0 1.61 1.79 2 0 0.349 E-3 0.687 E-7 0.224 E-7 0 4 0 0.246 E-3 0.323 E-5 0 0 31 50.00 -17.32 9.09 -21.92 3.5 10.88 2.5 6.0 1.61 1.79 2 0 0.204 E-3 0.113 E-6 0.561 E-8 0 4 0 0.335 E-3 -0.197 E-5 0 0 32 10.00 76.69 9.09 -68.03 3.5 7.16 2.5 6.0 1.61 1.79 2 0 0.264 E-3 -0.377 E-6 0.122 E-7 0 4 0 0.217 E-3 -0.56 E-6 0 0 33 20.00 -43.51 20.0 -14.05 3.5 6.66 2.5 8.0 1.61 1.79 2 0 0.295 E-3 0.680 E-6 0.288 E-7 0 4 0 0.141 E-3 -0.339 E-6 0 0 34 8.7 28.09 9.09 -177.9 3.5 6.07 2.5 4.0 1.61 1.79 2 0 0.264 E-3 -0.24 E-6 0.388 E-7 -0.2 E-9 3 0 -0.293 E-4 -0.442 E-5 0 0 35 9.43 -55.23 9.09 -90.43 3.5 7.78 2.5 4.0 1.61 1.79 2 0 0.322 E-3 -0.177 E-5 0.25 E-7 -0.1 E-9 3 0 -0.910 E-4 -0.153 E-7 0 0 36 14.29 82.09 10.0 -28.32 1.5 9.63 1.5 8.0 1.61 1.79 2 0 0.170 E-3 0.423 E-6 0.161 E-7 0 3 0 -0.192 E-3 -0.149 E-5 0 0 37 11.11 -141.85 9.09 -71.37 1.5 8.87 1.5 6.0 1.61 1.79 2 0 0.19 E-3 -0.635 E-6 0.1 E-7 0 3 0 -0.148 E-3 -0.341 E-5 0 0 38 8.33 89.51 16.67 -26.6 3.5 5.48 2.5 6.0 1.61 1.79 2 0 0.348 E-3 -0.111 E-5 0.328 E-7 -0.3 E-9 3 0 -0.17 E-3 -0.635 E-5 0 0 39 20.00 -34.29 9.09 -23.23 3.5 9.87 2.5 6.0 1.61 1.79 2 0 0.178 E-3 0.134 E-6 0.209 E-7 0 3 0 -0.221 E-3 -0.397 E-5 0 0 40 9.43 25.15 11.11 -82.02 3.5 6.21 2.5 6.0 1.79 1.89 2 0 0.236 E-3 -0.452 E-8 0.178 E-7 0 3 0 -0.14 E-3 -0.238 E-5 0 0 41 9.43 -33.61 9.09 -12.56 3.5 7.06 2.5 5.0 1.51 1.51 2 0 0.387 E-3 -0.15 E-5 0.27 E-7 0 3 0 -0.349 E-3 -0.185 E-4 0 0 42 9.43 46.17 9.09 -55.72 3.5 7.15 2.5 6.0 1.61 1.79 2 0 0.276 E-3 -0.123 E-6 0.223 E-7 0 3 0 -0.161 E-3 -0.342 E-5 0 0 TABLE 3 __________________________________________________________________________ Example 1 2 3 4 5 6 __________________________________________________________________________ R1 22.19 20.00 19.23 20.00 33.33 20.83 R2 -16.39 -27.10 -20.61 -18.09 -11.61 -16.82 R3 16.67 16.67 16.67 12.5 100.00 16.67 R4 -22.0 -18.57 -17.17 -61.03 -13.15 -17.07 R5 12.5 12.5 8.33 12.5 12.5 12.5 R6 -88.05 45.56 21.47 -39.96 -39.96 61.08 l1 3.5 3.5 3.5 3.5 3.5 3.5 l2 7.4 6.14 7.72 7.38 7.3 7.27 l3 2.5 2.5 2.5 2.5 2.5 2.5 l4 0.2 0.2 0.2 0.2 0.2 0.2 l5 2.0 2.0 2.0 2.0 2.0 2.0 s' 4.57 6.0 4.5 4.5 4.5 4.5 n1 1.61 1.61 1.61 1.61 1.61 1.61 n3 1.51 1.51 1.51 1.51 1.51 1.51 n5 1.51 1.51 1.51 1.51 1.51 1.51 aspher. 1 1 1 1 1 1 surface R K -20.318 -20.0 -20.0 -20.0 -20.0 -20.0 AC4 0 0.116 E-3 0.15 E-3 0.11 E-3 -0.284 E-3 0.461 E-3 AC6 -0.359 E-5 -0.545 E-5 - 0.679 E-5 -0.61 E-5 -0.706 E-6 -0.511 E-5 AC8 0.33 E-7 0.485 E-7 0.769 E-7 0.76 E-7 -0.397 E-8 0.569 E-7 AC10 0 0 0 0 0 0 __________________________________________________________________________ Example 7 8 9 10 11 12 __________________________________________________________________________ R1 28.46 20.46 28.46 16.13 16.67 20.00 R2 -16.98 -14.17 -35.61 195.38 -35.03 -13.77 R3 16.67 16.67 16.67 16.67 16.67 16.67 R4 -19.72 -23.48 -46.27 -15.05 -21.4 -406.33 R5 12.5 12.5 12.5 12.5 12.50 10.0 R6 327.48 -39.96 38.95 41.36 -62.16 -18.38 l1 5.0 3.5 3.5 3.5 3.5 3.5 l2 5.93 7.76 8.8 4.79 6.91 7.44 l3 4.0 2.5 2.5 2.5 2.5 2.5 l4 0.2 0.2 0.2 0.2 0.2 0.2 l5 3.0 2.0 2.0 2.0 2.0 2.0 s' 4.5 4.5 4.5 5.0 3.0 3.7 n1 1.61 1.61 1.79 1.61 1.61 1.61 n3 1.51 1.51 1.79 1.51 1.51 1.51 n5 1.51 1.51 1.79 1.51 1.51 1.51 aspher. 1 1 1 1 1 1 surface R K -20.0 - 20.0 -20.0 0 0 -20.0 AC4 -0.101 E-3 -0.149 E-3 -0.218 E-3 -0.169 E-3 -0.135 E-3 0.428 E-3 AC6 -0.119 E-5 -0.107 E-5 -0.108 E-5 -0.11 E-5 -0.418 E-6 -0.619 E-5 AC8 0.249 E-9 0.669 E-9 0.314 E-8 -0.215 E-7 -0.685 E-8 0.8 E-7 AC10 0 0 0 0 0 0 __________________________________________________________________________ E-3 means 10.sup.-3 wherein R equals the radius of curvature of the lens surface with the numerals thereafter denoting which surface in said direction of incidence; l indicating the spacing between lens surfaces along a center line in said direction of incidences with the numeral 1 being the distance between the first and second lens surface, numeral 2 between the second and third lens surfaces, and numeral 3 between the third and fourth lens surface; s' being the intercept length; n is the index of refraction of the lens material with the numeral 1 designating the lens material between lens surfaces 1 and 2, and numeral 3 designating the lens material between lens surfaces 3 and 4; and wherein K, AC4, AC6, AC8 and AC10 are spherical coefficients used to determine a meniscus height of an aspherical surface represented by the following equation wherein ##EQU3## and wherein h is a distance of a surface point from an optical axis and is φ a surface vertex.

Claim 17

A scanning objective characterized by two lens means with positive power of refraction which both have an aspherical surface which are so constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside, and in which the respective surface on the side of the larger intercept length is more strongly curved and wherein an outer diameter of the first lens is reduced by about one-half, the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature ( surface distance measured in the direction of the optical axis) is reduced by more than a factor of 4, and in that this factor decreases from the outside toward the inside.

Claim 18

A scanning objective characterized by two lens means with positive power of refraction which both have an aspherical surface which are so constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside, and in which the respective surface on the side of the larger intercept length is more strongly curved and wherein an outer diameter of the first lens is reduced by about one-half, the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature ( surface distance measured in the direction of the optical axis) is reduced by more than a factor of 4, and in that this factor decreases from the outside toward the inside.

Claim 19

A scanning objective according to claim 13, characterized in that the factor by which the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature is reduced lies for a space between an edge and half-diameter of the first lens between about 8 and 80 and for a space between a half and quarter diameter of the first lens between 5 and 50.

Claim 20

A scanning objective characterized by two lens means with positive power of refraction which both have an aspherical surface which are so constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside, and in which the respective surface on the side of the larger intercept length is more strongly curved and wherein the following values for the relative deviation Δz of the aspherical surface from a spherical surface with the same vertex radius of curvature: ______________________________________ h 0.1 0.2 0.3 0.4 0.5 0.6 Δz 0.005 0.03 0.11 0.4 1.0 2.2 ______________________________________ whereby the focal distance f as well as the relative deviation Δz ( surface distance measured in the direction of the optical axis) is normalized to 1 with a distance h from the optical axis of 0.5.

Claim 21

A scanning objective characterized by two lens means with positive power of refraction which both have an aspherical surface which are so constructed that in comparison with a spherical surface with the same vertex radius of curvature, the thickness of the lens means increases toward the outside, and in which the respective surface on the side of the larger intercept length is more strongly curved and wherein the following values for the relative deviation Δz of the aspherical surface from a spherical surface with the same vertex radius of curvature: ______________________________________ h 0.1 0.2 0.3 0.4 0.5 0.6 Δz 0.005 0.03 0.11 0.4 1.0 2.2 ______________________________________ whereby the focal distance f as well as the relative deviation Δz ( surface distance measured in the direction of the optical axis) is normalized to 1 with a distance h from the optical axis of 0.5.

Claim 22

A scanning objective characterized by two optical members with positive power of refraction, of which the first member as viewed in the direction of incidence of the beam consists of a lens means which has an aspherical surface so constructed that in comparison with a spherical surface having the same vertex radius of curvature, the thickness of the lens means increases toward the outside, and in that the second optical element consists of two lens means and wherein an outer diameter of the first lens is reduced by about one-half, the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature (Δ surface distance measured in the direction of the optical axis) is reduced by more than a factor of 4, and in that this factor decreases from the outside toward the inside.

Claim 23

A scanning objective characterized by two optical members with positive power of refraction, of which the first member as viewed in the direction of incidence of the beam consists of a lens means which has an aspherical surface so constructed that in comparison with a spherical surface having the same vertex radius of curvature, the thickness of the lens means increases toward the outside, and in that the second optical element consists of two lens means and wherein an outer diameter of the first lens is reduced by about one-half, the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature (Δ surface distance measured in the direction of the optical axis) is reduced by more than a factor of 4, and in that this factor decreases from the outside toward the inside.

Claim 24

A scanning objective according to claim 16, characterized in that the factor by which the deviation of the aspherical surface from a spherical surface with the same vertex radius of curvature is reduced lies for a space between an edge and half-diameter of the first lens between about 8 and 80 and for a space between a half and quarter diameter of the first lens between 5 and 50.

Claim 25

A scanning objective characterized by two optical members with positive power of refraction, of which the first member as viewed in the direction of incidence of the beam consists of a lens means which has an aspherical surface so constructed that in comparison with a spherical surface having the same vertex radius of curvature, the thickness of the lens means increases toward the outside, and in the second optical element consists of two lens means and wherein the following values for the relative deviation Δz of the aspherical surface from a spherical surface with the same vertex radius of curvature: ______________________________________ h 0.1 0.2 0.3 0.4 0.5 0.6 Δz 0.005 0.03 0.11 0.4 1.0 2.2 ______________________________________ whereby the focal distance f as well as the relative deviation Δz ( surface distance measured in the direction of the optical axis) is normalized to 1 with a distance h from the optical axis of 0.5.

Claim 26

A scanning objective characterized by two optical members with positive power of refraction, of which the first member as viewed in the direction of incidence of the beam consists of a lens means which has an aspherical surface so constructed that in comparison with a spherical surface having the same vertex radius of curvature, the thickness of the lens means increases toward the outside, and in the second optical element consists of two lens means and wherein the following values for the relative deviation Δz of the aspherical surface from a spherical surface with the same vertex radius of curvature: ______________________________________ h 0.1 0.2 0.3 0.4 0.5 0.6 Δz 0.005 0.03 0.11 0.4 1.0 2.2 ______________________________________ whereby the focal distance f as well as the relative deviation Δz ( surface distance measured in the direction of the optical axis) is normalized to 1 with a distance h from the optical axis of 0.5.