Constant-speed scanning lens system

Claim 2

A constant-speed scanning lens system comprising a first, second, third, fourth and fifth lens components, said first lens component being a positive meniscus lens arranged concave toward the incident side, said second lens component being a negative lens, said third lens component being a positive meniscus lens arranged concave toward the incident side, said fourth lens component being a positive meniscus lens arranged concave toward the incident side, said fifth lens component being a positive meniscus lens arranged concave toward the incident side, said constant-speed scanning lens system satisfying the following conditions: (1) 1.02<|r 2 /r 3 |<1.12 (2) 0.013f<d 4 <0.016f (3) -0.245f<r 1 <-0.185f (4) -6.8f<r 5 <-1.7f wherein reference symbols r 1 , r 2 , r 3 and r 5 respectively represent radii of curvature of respective surfaces of the first lens component, surface on the incident side of the second lens component and surface on the incident side of the third lens component, reference symbol d 4 represents the airspace between the second and third lens components, and reference symbol f represents the focal length of the lens systems as a whole.

Claim 3

A constant-speed scanning lens system according to claim 1, in which said constant-speed scanning lens system has the following numerical data: ______________________________________ r.sub.1 = -0.2012 d.sub.1 = 0.0171 n.sub.1 = 1.63612 ν.sub.1 = 55.4 r.sub.2 = -0.1583 d.sub.2 = 0.0191 r.sub.3 = -0.1501 d.sub.3 = 0.0163 n.sub.2 = 1.56459 ν.sub.2 = 42.8 r.sub.4 = 39.1220 d.sub.4 = 0.0138 r.sub.5 = -3.5473 d.sub.5 = 0.0298 n.sub.3 = 1.61985 ν.sub.3 = 53.2 r.sub.6 = -0.6373 d.sub.6 = 0.0008 r.sub.7 = -1.0971 d.sub.7 = 0.0420 n.sub.4 = 1.61985 ν.sub.4 = 53.2 r.sub.8 = -0.3136 d.sub.8 = 0.0008 r.sub.9 = -1.2448 d.sub.9 = 0.0393 n.sub.5 = 1.61985 ν.sub.5 = 53.2 r.sub. 10 = -0.4265 f = 1 F/23.7 y = 0.589 |r.sub.2 /r.sub.3 | = 1.054 λ = 632.8 nm ______________________________________ wherein reference symbols r 1 through r 10 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 through d 9 respectively represent thicknesses of respective lenses and airspaces between lenses, reference symbols n 1 through n 5 respectively represent refractive indices of respective lenses at the wavelength of 632.8 nm, reference symbols ν 1 through ν 5 respectively represent Abbe's numbers of respective lenses for d-line, reference symbol f represents the focal length of the lens system as a whole, reference symbol F represents the F number, and reference symbol y represents the image height.

Claim 4

A constant-speed scanning lens system according to claim 1, in which said constant-speed scanning lens system has the following numerical data: ______________________________________ r.sub.1 =-0.2037 d.sub.1 = 0.0171 n.sub.1 = 1.63612 ν.sub.1 = 55.4 r.sub.2 = -0.1573 d.sub.2 = 0.0191 r.sub.3 = -0.1479 d.sub.3 = 0.0163 n.sub.2 = 1.56459 ν.sub.2 = 42.8 r.sub.4 = 5.4560 d.sub.4 = 0.0138 r.sub.5 = -6.1854 d.sub.5 = 0.0298 n.sub.3 = 1.61985 ν.sub.3 = 53.2 r.sub.6 =-0.5090 d.sub.6 = 0.0008 r.sub.7 =-1.0001 d.sub.7 = 0.0420 n.sub.4 = 1.61985 ν.sub.4 = 53.2 r.sub.8 = -0.3543 d.sub.8 = 0.0008 r.sub.9 = -0.9159 d.sub.9 = 0.0393 n.sub.5 = 1.61985 ν.sub.5 = 53.2 r.sub.10 = -0.3684 f = 1 F/23.7 y = 0.589 |r.sub.2 /r.sub.3 | = 1.064 λ= 632.8 nm ______________________________________ wherein reference symbols r 1 through r 10 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 through d 9 respectively represent thicknesses of respective lenses and airspaces between lenses, reference symbols n 1 through n 5 respectively represent refractive indices of respective lenses at the wavelength of 632.8 nm, reference symbols ν 1 through ν 5 respectively represent Abbe's numbers of respective lenses for d-line, reference symbol f represents the focal length of the lens system as a whole, reference symbol F represents the F number, and reference symbol y represents the image height.

Claim 5

A constant-speed scanning lens system according to claim 1, in which said constant-speed scanning lens system has the following numerical data: ______________________________________ r.sub.1 = -0.1993 d.sub.1 = 0.0171 n.sub.1 = 1.63612 ν.sub.1 = 55.4 r.sub.2 = -0.1565 d.sub.2 = 0.0191 r.sub.3 = -0.1488 d.sub.3 = 0.0163 n.sub.2 = 1.56459 ν.sub.2 = 42.8 r.sub.4 = ∞ d.sub.4 = 0.0138 r.sub.5 = -3.3866 d.sub.5 = 0.0298 n.sub.3 = 1.61985 ν.sub.3 = 53.2 r.sub.6 = -0.5834 d.sub.6 = 0.0008 r.sub.7 = -1.0150 d.sub.7 = 0.0420 n.sub.4 = 1.61985 ν.sub.4 = 53.2 r.sub.8 = -0.3194 d.sub.8 = 0.0008 r.sub.9 = -1.1748 d.sub.9 = 0.0393 n.sub.5 = 1.61985 ν.sub.5 = 53.2 r.sub.10 = -0.4171 d.sub.10 = 1.2166 r.sub.11 = ∞ d.sub.11 = 0.0135 n.sub.6 = 1.51462 ν.sub.6 = 64.1 r.sub.12 = ∞ f = 1 F/23.7 y = 0.555 |r.sub.2 /r.sub.3 | = 1.052 λ = 632.8nm ______________________________________ wherein reference symbols r 1 through r 12 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 through d 11 respectively represent thicknesses of respective lenses and airspaces between lenses, reference symbols n 1 through n 6 respectively represent refractive indices of respective lenses at the wavelength of 632.8 nm, reference symbols ν 1 through ν 6 respectively represent Abbe's numbers of respective lenses for d-line, reference symbol f represents the focal length of the lens sytstem as a whole, reference symbol F represents the F number, and reference symbol y represents the image height.

Claim 6

A constant-speed scanning lens system according to claim 1, in which said constant-speed scanning lens system has the following numerical data: ______________________________________ r.sub.1 = -0.2023 d.sub.1 = 0.0171 n.sub.1 = 1.63612 ν.sub.1 = 55.4 r.sub.2 = -0.1586 d.sub.2 = 0.0191 r.sub.3 = -0.1500 d.sub.3 = 0.0163 n.sub.2 = 1.56459 ν.sub.2 = 42.8 r.sub.4 = 78.8505 d.sub.4 = 0.0145 r.sub.5 = -3.3040 d.sub.5 = 0.0298 n.sub.3 = 1.61985 ν.sub.3 = 53.2 r.sub.6 = -0.6149 d.sub.6 = 0.0008 r.sub.7 = -1.1101 d.sub.7 = 0.0420 n.sub.4 = 1.61985 ν.sub.4 = 53.2 r.sub.8 = -0.3137 d.sub.8 = 0.0008 r.sub.9 = -1.1696 d.sub.9 = 0.0393 n.sub.5 = 1.61985 ν.sub.5 = 53.2 r.sub.10 = -0.4282 f = 1 F/23.7 y = 0.589 |r.sub.2 /r.sub.3 | = 1.058 λ = 632.8 nm ______________________________________ wherein reference symbols r 1 through r 10 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 through d 9 respectively represent thicknesses of respective lenses and airspaces between lenses, reference symbols n 1 through n 5 respectively represent refractive indices of respective lenses at the wavelength of 632.8 nm, reference symbols ν 1 through ν 5 respectively represent Abbe's numbers of respective lenses for d-line, reference symbol f represents the focal length of the lens system as a whole, reference symbol F represents the F number, and reference symbol y represents the image height.

Claim 7

A constant-speed scanning lens system according to claim 1, in which said constant-speed scanning lens system has the following numerical data: ______________________________________ r.sub.1 = -0.1932 d.sub.1 = 0.0171 n.sub.1 = 1.63612 ν.sub.1 = 55.4 r.sub.2 = -0.1525 d.sub.2 = 0.0191 r.sub.3 = -0.1472 d.sub.3 = 0.0163 n.sub.2 = 1.56459 ν.sub.2 = 42.8 r.sub.4 = -4.0709 d.sub.4 = 0.0133 r.sub.5 = -2.2468 d.sub.5 = 0.0298 n.sub.3 = 1.61985 ν.sub.3 = 53.2 r.sub.6 = -0.5051 d.sub.6 = 0.0008 r.sub.7 = -0.7321 d.sub.7 = 0.0420 n.sub.4 = 1.61985 ν.sub.4 = 53.2 r.sub.8 = -0.3286 d.sub.8 = 0.0008 r.sub.9 = -1.4918 d.sub.9 = 0.0393 n.sub.5 = 1.61985 ν.sub.5 = 53.2 r.sub. 10 = -0.4171 d.sub.10 = 1.2166 r.sub.11 = ∞ d.sub.11 = 0.0135 n.sub.6 = 1.51462 ν.sub.6 = 64.1 r.sub.12 = ∞ f = 1 F/23.7 y = 0.555 |r.sub.2 /r.sub.3| = 1.036 λ = 632.8 nm ______________________________________ wherein reference symbols r 1 through r 12 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 through d 11 respectively represent thicknesses of respective lenses and airspaces between lenses, reference symbols n 1 through n 6 respectively represent refractive indices of respective lenses at the wavelength of 632.8 nm, reference symbols ν 1 through ν 6 respectively represent Abbe's numbers of respective lenses for d-line, reference symbol f represents the focal length of the lens system as a whole, reference symbol F represents the F number, and reference symbol y represents the image height.

Claim 8

A constant-speed scanning lens system according to claim 1, in which said constant-speed scanning lens system has the following numerical data: ______________________________________ r.sub.1 = -0.2104 d.sub.1 = 0.0200 n.sub.1 = 1.64488 ν.sub.1 = 60.1 r.sub.2 = -0.1608 d.sub.2 = 0.0184 r.sub.3 = -0.1498 d.sub.3 = 0.0195 n.sub.2 = 1.57343 ν.sub.2 = 42.8 r.sub.4 = 7.7024 d.sub.4 = 0.0154 r.sub.5 = -4.4646 d.sub.5 = 0.0274 n.sub.3 = 1.62791 ν.sub.3 = 58.2 r.sub.6 = -0.5157 d.sub.6 = 0.0022 r.sub.7 = -1.1407 d.sub.7 = 0.0362 n.sub.4 = 1.62791 ν.sub.4 = 58.2 r.sub.8 = -0.3560 d.sub.8 = 0.0022 r.sub.9 = -0.8187 d.sub.9 = 0.0350 n.sub.5 = 1.62791 ν.sub.5 = 58.2 r.sub.10 = - 0.3713 d.sub.10 = 1.2153 r.sub.11 = ∞ d.sub.11 = 0.0135 n.sub.6 = 1.52002 ν.sub.6 = 64.1 r.sub.12 = ∞ f = 1 F/29.15 y = 0.555 |r.sub.2 /r.sub.3 | = 1.073 λ = 514.5 nm ______________________________________ wherein reference symbols r 1 through r 12 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 through d 11 respectively represent thicknesses of respective lenses and airspaces between lenses, reference symbols n 1 through n 6 respectively represent refractive indices of respective lenses at the wavelength of 514.5 nm, reference symbols ν 1 through ν 6 respectively represent Abbe's numbers of respective lenses for d-line, reference symbol f respresents the focal length of the lens system as a whole, reference symbol F represents the F number, and reference symbol y represents the image height.

Claim 9

A constant-speed scanning lens system according to claim 1, in which said constant-speed scanning lens system has the following numerical data: ______________________________________ r.sub.1 = -0.2138 d.sub.1 = 0.0198 n.sub.1 = 1.64384 ν.sub.1 = 55.4 r.sub.2 = -0.1614 d.sub.2 = 0.0193 r.sub.3 = -0.1497 d.sub.3 = 0.0190 n.sub.2 = 1.57343 ν.sub.2 = 42.8 r.sub.4 = 26.5199 d.sub.4 = 0.0153 r.sub.5 = -3.3375 d.sub.5 = 0.0271 n.sub.3 = 1.62768 ν.sub.3 = 53.2 r.sub.6 = -0.5019 d.sub.6 = 0.0027 r.sub.7 = -1.1722 d.sub.7 = 0.0371 n.sub.4 = 1.62768 ν.sub.4 = 53.2 r.sub.8 = -0.3583 d.sub.8 = 0.0027 r.sub.9 = -0.7758 d.sub.9 = 0.0342 n.sub.5 = 1.62768 ν.sub.5 = 53.2 r.sub. 10 = -0.3722 f = 1 F/24.77 ν = 0.555 |r.sub.2 /r.sub.3 | = 1.078 λ = 514.5 nm ______________________________________ wherein reference symbols r 1 through r 10 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 through d 9 respectively represent thicknesses of respective lenses and airspaces between lenses, reference symbols n 1 through n 5 respectively represent refractive indices of respective lenses at the wavelength of 514.5 nm, reference symbols ν 1 through ν 5 respectively represent Abbe's numbers of respective lenses for d-line, reference symbol f represents the focal length of the lens system as a whole, reference symbol F represents the F number, and reference symbol y represents the image height.

Claim 10

A constant-speed scanning lens system according to claim 1, in which said constant-speed scanning lens system has the following numerical data: ______________________________________ r.sub.1 = -0.2216 d.sub.1 = 0.0190 n.sub.1 = 1.64384 ν.sub.1 = 55.4 r.sub.2 = -0.1656 d.sub.2 = 0.0200 r.sub.3 = -0.1511 d.sub.3 = 0.0244 n.sub.2 = 1.57343 ν.sub.2 = 42.8 r.sub.4 = 6.8525 d.sub.4 = 0.0153 r.sub.5 = -4.7140 d.sub.5 = 0.0271 n.sub.3 = 1.62768 ν.sub.3 = 53.2 r.sub.6 = -0.4990 d.sub.6 = 0.0081 r.sub.7 = -1.2190 d.sub.7 = 0.0298 n.sub.4 = 1.62768 ν.sub.4 = 53.2 r.sub.8 = -0.3637 d.sub.8 = 0.0081 r.sub.9 = -0.7141 d.sub.9 = 0.0298 n.sub.5 = 1.62768 ν.sub.5 = 53.2 r.sub. 10 = -0.3638 f = 1 F/35 y = 0.589 |r.sub.2 /r.sub.3 | = 1.096 λ = 514.5 nm ______________________________________ wherein reference symbols r 1 through r 10 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 through d 9 respectively represent thicknesses of respective lenses and airspaces between lenses, reference symbols n 1 through n 5 respectively represent refractive indices of respective lenses at the wavelength of 514.5 nm, reference symbols ν 1 through ν 5 respectively represent Abbe's numbers of respective lenses for d-line, reference symbol f represents the focal length of the lens system as a whole, reference symbol F represents the F number, and reference symbol y represents the image height.

Claim 11

A constant-speed scanning lens system according to claim 1, in which said constant-speed scanning lens system has the following numerical data: ______________________________________ r.sub.1 = -0.2354 d.sub.1 = 0.0187 n.sub.1 = 1.64384 ν.sub.1 = 55.4 r.sub.2 = -0.1691 d.sub.2 = 0.0183 r.sub.3 = -0.1525 d.sub.3 = 0.0279 n.sub.2 = 1.57343 ν.sub.2 = 42.8 r.sub.4 = 5.1238 d.sub.4 = 0.0153 r.sub.5 = -5.8207 d.sub.5 = 0.0271 n.sub.3 = 1.62768 ν.sub.3 = 53.2 r.sub.6 = -0.6053 d.sub.6 = 0.0081 r.sub.7 = -1.2320 d.sub.7 = 0.0298 n.sub.4 = 1.62768 ν.sub.4 = 53.2 r.sub.8 = -0.3855 d.sub.8 = 0.0081 r.sub.9 = -0.8546 d.sub.9 = 0.0298 n.sub.5 = 1.62768 ν.sub.5 = 53.2 r.sub. 10 = -0.3529 f = 1 F/35 y = 0.589 |r.sub.2 /r.sub.3 | = 1.109 λ = 514.5 nm ______________________________________ wherein reference symbols r 1 through r 10 respectively represent radii of curvature of respective lens surfaces, reference symbols d 1 through d 9 respectively represent thicknesses of respective lenses and airspaces between lenses, reference symbols n 1 through n 5 respectively represent refractive indices of respective lenses at the wavelength of 514.5 nm, reference symbols ν 1 through ν 5 respectively represent Abbe's numbers of respective lenses for d-line, reference symbol f represents the focal length of the lens system as a whole, reference symbol F represents the F number, and reference symbol y represents the image height.