US3773402A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pancratic lens
Assignee: Individual
•
Filing: 1970-09-15
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Granted: 1973-11-20
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Expires: 1990-09-15
Abstract
Abstract The lens comprises a rear lens unit having a fixed focal length and a pancratic lens supplement having a variable magnification factor. The pancratic lens supplement comprises a stationary, positive first lens unit, an axially displaceable, negative second lens unit succeeding the first lens unit, an axially displaceable, positive third lens unit succeeding the second lens unit, and a stationary, negative fourth lens unit succeeding the third lens unit. The second and third lens units are adjustable to a first position, in which the lens has a smallest focal length fGmin, and to a second position in which said lens has a largest focal length fmax. The third lens unit has in both the first and second positions a magnification factor Beta 3 meeting the following conditions:
Inventors
- 👤 H Gela
- 👤 T Muszumanski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:51
CPC Classifications
G; G02; G02B; G02B15/00; G02B15/14; G02B15/22
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
637 words
A pancratic lens supplement having a continuously variable magnification factor and designed like a Galilean telescope, said pancratic lens supplement comprising a stationary, positive first lens unit, an axially displaceable, negative second lens unit succeeding said first lens unit, an axially displaceable, positive third lens unit succeeding said second lens unit, and a stationary, negative fourth lens unit succeeding said third lens unit, said first lens unit consisting of a negative first lens component and a positive second lens component spaced behind said first lens component, said first and second lens components having focal lengths of about -420%fI and about 90%fI, respectively, where fI is the focal length of said first lens unit, said second lens unit consisting of third and fourth lens components, said third lens component consisting of a negative meniscus convexly curved toward the light-receiving side and consisting of a biconvex lens element and a biconcave lens element cemented to said biconvex lens element, said fourth lens component consisting of a biconcave lens element having almost equal sides, said third lens unit consisting of a biconvex lens component anD a positive meniscus having about the same refractive power, said fourth lens unit consisting of a single biconcave lens element having a less steeply curved surface facing said third lens unit, said first lens component consists of a biconcave lens element and a biconvex lens element, which define between them a rearwardly concave, negative air meniscus, said second lens component consists of a biconvex lens element having equal sides and a positive meniscus having rearwardly concave surfaces and said biconvex lens component of said third lens unit consists of a negative meniscus which is convexly curved toward said second lens unit and a biconvex lens element having substantially equal sides and which has the following data: r1-67.2 d1 1.9/nd1 1.805 vd1 25.4 r2+105 d2 1.9 r3+116 d3 8.3/nd3 1.574 vd3 56.4 r4-60.8 d4 4.9 r5+187 d5 4.4/nd5 1.643 vd5 48.0 r6-187 d6 0.1 r7+45.4 d7 5.7/nd7 1.658 vd7 50.9 r8+166 d8 0.8/nd8 -29.3 r9+93.2 d9 3.8/nd9 1.805 vd9 25.4 r10-52.2 d10 1.0/nd10 1.620 vd10 60.3 phi 10 0.00354 r11+16.6 d11 4.9 phi 11 -0.03746 r12-37.9 d12 1.0/nd12 1.744 vd12 44.8 r13+41.2 d13 41.8/nd13 -2.0 r14+77.7 d14 0.8/nd14 1.741 vd14 27.6 r15+30.0 d15 3.8/nd15 1.652 vd15 44.9 r16-30.0 d16 0.1 r17+19.9 d17 2.7/nd17 1.720 vd17 50.4 r18+78.2 d18 2.8/nd18 -14.1 r19-41.1 d19 0.9/nd19 1.620 vd19 60.3 r20+17.4 fI 61.174 phi I 0.00686 phi I 0.01074 phi II 0.02493 phi II -0.03789 phi III -0.01499 phi III 0.02787 phi III 0.04230 phi III 0.05515 phi III 0.02749 wherein r1, r2, ... r20 are in millimeters the radii of curvature of successive boundary surfaces of lens elements, d1, d2, ... d19 are in millimeters the center distances between successive boundary surfaces of lens elements, nd1, nd3, ... nd19 are the indices of refraction of media having center thicknesses d1, d3, ... d19, respectively, vd1, vd3, ... vd19 are the Abbe numbers of lens elements having center thicknesses d1, d3, ... d19, fI is the focal length of the first lens unit, phi 10 and phi 11 are, respectively, the refractive powers of the forward and rear surfaces of said biconvex lens element of said third lens component, phi I and phi I are, respectively, the refractive powers of the biconvex lens element and of the meniscus of said second lens component, phi II and phi II are, respectively, the refractive powers of said third and fourth lens components, wherein phi III and phi III are, Respectively, the refractive powers of said meniscus and said biconvex lens element of said biconvex lens component, phi III and phi III are, respectively, the refractive powers of said biconvex lens component and said positive meniscus of said third lens unit, and phi III is the refractive power of said third lens unit.
Claim 2
Dependent Claim
637 words
A pancratic lens supplement having a continuously variable magnification factor and designed like a Galilean telescope, said pancratic lens supplement comprising a stationary, positive first lens unit, an axially displaceable, negative second lens unit succeeding said first lens unit, an axially displaceable, positive third lens unit succeeding said second lens unit, and a stationary, negative fourth lens unit succeeding said third lens unit, said first lens unit consisting of a negative first lens component and a positive second lens component spaced behind said first lens component, said first and second lens components having focal lengths of about -420%fI and about 90%fI, respectively, where fI is the focal length of said first lens unit, said second lens unit consisting of third and fourth lens components, said third lens component consisting of a negative meniscus convexly curved toward the light-receiving side and consisting of a biconvex lens element and a biconcave lens element cemented to said biconvex lens element, said fourth lens component consisting of a biconcave lens element having almost equal sides, said third lens unit consisting of a biconvex lens component anD a positive meniscus having about the same refractive power, said fourth lens unit consisting of a single biconcave lens element having a less steeply curved surface facing said third lens unit, said first lens component consists of a biconcave lens element and a biconvex lens element, which define between them a rearwardly concave, negative air meniscus, said second lens component consists of a biconvex lens element having equal sides and a positive meniscus having rearwardly concave surfaces and said biconvex lens component of said third lens unit consists of a negative meniscus which is convexly curved toward said second lens unit and a biconvex lens element having substantially equal sides and which has the following data: r1-67.2 d1 1.9/nd1 1.805 vd1 25.4 r2+105 d2 1.9 r3+116 d3 8.3/nd3 1.574 vd3 56.4 r4-60.8 d4 4.9 r5+187 d5 4.4/nd5 1.643 vd5 48.0 r6-187 d6 0.1 r7+45.4 d7 5.7/nd7 1.658 vd7 50.9 r8+166 d8 0.8/nd8 -29.3 r9+93.2 d9 3.8/nd9 1.805 vd9 25.4 r10-52.2 d10 1.0/nd10 1.620 vd10 60.3 phi 10 0.00354 r11+16.6 d11 4.9 phi 11 -0.03746 r12-37.9 d12 1.0/nd12 1.744 vd12 44.8 r13+41.2 d13 41.8/nd13 -2.0 r14+77.7 d14 0.8/nd14 1.741 vd14 27.6 r15+30.0 d15 3.8/nd15 1.652 vd15 44.9 r16-30.0 d16 0.1 r17+19.9 d17 2.7/nd17 1.720 vd17 50.4 r18+78.2 d18 2.8/nd18 -14.1 r19-41.1 d19 0.9/nd19 1.620 vd19 60.3 r20+17.4 fI 61.174 phi I 0.00686 phi I 0.01074 phi II 0.02493 phi II -0.03789 phi III -0.01499 phi III 0.02787 phi III 0.04230 phi III 0.05515 phi III 0.02749 wherein r1, r2, ... r20 are in millimeters the radii of curvature of successive boundary surfaces of lens elements, d1, d2, ... d19 are in millimeters the center distances between successive boundary surfaces of lens elements, nd1, nd3, ... nd19 are the indices of refraction of media having center thicknesses d1, d3, ... d19, respectively, vd1, vd3, ... vd19 are the Abbe numbers of lens elements having center thicknesses d1, d3, ... d19, fI is the focal length of the first lens unit, phi 10 and phi 11 are, respectively, the refractive powers of the forward and rear surfaces of said biconvex lens element of said third lens component, phi I and phi I are, respectively, the refractive powers of the biconvex lens element and of the meniscus of said second lens component, phi II and phi II are, respectively, the refractive powers of said third and fourth lens components, wherein phi III and phi III are, Respectively, the refractive powers of said meniscus and said biconvex lens element of said biconvex lens component, phi III and phi III are, respectively, the refractive powers of said biconvex lens component and said positive meniscus of said third lens unit, and phi III is the refractive power of said third lens unit.
Claim 3
Dependent Claim
628 words
A pancratic lens supplement having a continuously variable magnification factor and designed like a Galilean telescope, said pancratic lens supplement comprising a stationary, positive first lens unit, an axially displaceable, negative second lens unit succeeding said first lens unit, an axially displaceable, positive third lens unit succeeding said second lens unit, and a stationary, negative fourth lens unit succeeding said third lens unit, said first lens unit consisting of a negative first lens component and a positive second lens component spaced behind said first lens component, said first and second lens components having focal lengths of about -420%fI and about 90%fI, respectively, where fI is the focal length of said first lens unit, said second lens unit consisting of third and fourth lens components, said third lens component consisting of a negative meniscus convexly curved toward the light-receiving side and consisting of a biconvex lens element and a biconcave lens element cemented to said biconvex lens element, said fourth lens component consisting of a biconcave lens element having almost equal sides, said third lens unit consisting of a biconvex lens component and a positive meniscus having about the same refractive power, said fourth lens unit consisting of a single biconcave lens element having a less steeply curved surface facing said third lens unit, said first lens component consists of a biconcave lens element and a biconvex lens element, which define between them a rearwardly concave, negative air meniscus, said second lens component consists of a biconvex lens element having equal sides and a positive meniscus having rearwardly concave surfaces and said biconvex lens component of said third lens unit consists of a negative meniscus which is convexly curved toward said second lens unit and a biconvex lens element having substantially equal sides and which has the following data: r1-67.2 d1 1.9/nd1 1.805 vd1 25.4 r2+105 d2 1.9 r3+116 d3 8.3/nd3 1.574 vd3 56.4 r4-60.8 d4 4.9 r5+187 d5 4.4/nd5 1.643 vd5 48.0 r6-187 d6 0.1 r7+45.4 d7 5.7/nd7 1.658 vd7 50.9 r8+166 d8 0.8/nd8 -29.3 r9+93.2 d9 3.8/nd9 1.805 vd9 25.4 r10-52.2 d10 1.0/nd10 1.620 vd10 60.3 phi 10 0.00354 r11+16.6 d11 4.9 phi 11 -0.03746 r12-37.9 d12 1.0/nd12 1.744 vd12 44.8 r13+41.2 d13 41.8/nd13 -2.0 r14+77.7 d14 0.8/nd14 1.741 vd14 27.6 r15+30.0 d15 3.8/nd15 1.652 vd15 44.9 r16-30.0 d16 0.1 r17+19.9 d17 2.7/nd17 1.717 vd17 48.0 r18+78.7 d18 2.8/nd18 -14.1 r19-40.0 d19 0.9/nd19 1.620 vd19 60.3 r20+17.6 fI 61.174 phi I 0.00686 phi I 0.01074 phi II -0.02493 phi II -0.03789 phi III -0.01499 phi III 0.02787 phi III 0.04230 phi III 0.05515 phi III 0.02749 wherein r1, r2, ... r20 are in millimeters the radii of curvature of successive boundary surfaces of lens elements, d1, d2, ... d19 are in millimeters the center distances between successive boundary surfaces of lens elements, nd1, nd3, ... nd19 are the indices of refraction of media having center thicknesses d1, d3, ... d19, respectively, vd1, vd3, ... vd19 are the Abbe numbers of lens elements having center thicknesses d1, d3, ... d19, fI is the focal length of the first lens unit, phi 10 and phi 11 are, respectively, the refractive powers of the forward and rear surfaces of said biconvex lens element of said third lens component, phi I and phi I are, respectively, the refractive powers of said second lens component, phi II and phi II are, respectively, the refractive powers of said third and fourth lens components, wherein phi III and phi III are, respectively, the refractive powers of said meniscus and said biconvex lens element of said biconvex lens component, phi III and phi III are, respectively, the refractive powers of said biconvex lens component and said positive meniscus of said third lens unit, and phi III is the refractive power of said third lens unit.
Claim 4
Dependent Claim
628 words
A pancratic lens supplement having a continuously variable magnification factor and designed like a Galilean telescope, said pancratic lens supplement comprising a stationary, positive first lens unit, an axially displaceable, negative second lens unit succeeding said first lens unit, an axially displaceable, positive third lens unit succeeding said second lens unit, and a stationary, negative fourth lens unit succeeding said third lens unit, said first lens unit consisting of a negative first lens component and a positive second lens component spaced behind said first lens component, said first and second lens components having focal lengths of about -420%fI and about 90%fI, respectively, where fI is the focal length of said first lens unit, said second lens unit consisting of third and fourth lens components, said third lens component consisting of a negative meniscus convexly curved toward the light-receiving side and consisting of a biconvex lens element and a biconcave lens element cemented to said biconvex lens element, said fourth lens component consisting of a biconcave lens element having almost equal sides, said third lens unit consisting of a biconvex lens component and a positive meniscus having about the same refractive power, said fourth lens unit consisting of a single biconcave lens element having a less steeply curved surface facing said third lens unit, said first lens component consists of a biconcave lens element and a biconvex lens element, which define between them a rearwardly concave, negative air meniscus, said second lens component consists of a biconvex lens element having equal sides and a positive meniscus having rearwardly concave surfaces and said biconvex lens component of said third lens unit consists of a negative meniscus which is convexly curved toward said second lens unit and a biconvex lens element having substantially equal sides and which has the following data: r1-67.2 d1 1.9/nd1 1.805 vd1 25.4 r2+105 d2 1.9 r3+116 d3 8.3/nd3 1.574 vd3 56.4 r4-60.8 d4 4.9 r5+187 d5 4.4/nd5 1.643 vd5 48.0 r6-187 d6 0.1 r7+45.4 d7 5.7/nd7 1.658 vd7 50.9 r8+166 d8 0.8/nd8 -29.3 r9+93.2 d9 3.8/nd9 1.805 vd9 25.4 r10-52.2 d10 1.0/nd10 1.620 vd10 60.3 phi 10 0.00354 r11+16.6 d11 4.9 phi 11 -0.03746 r12-37.9 d12 1.0/nd12 1.744 vd12 44.8 r13+41.2 d13 41.8/nd13 -2.0 r14+77.7 d14 0.8/nd14 1.741 vd14 27.6 r15+30.0 d15 3.8/nd15 1.652 vd15 44.9 r16-30.0 d16 0.1 r17+19.9 d17 2.7/nd17 1.717 vd17 48.0 r18+78.7 d18 2.8/nd18 -14.1 r19-40.0 d19 0.9/nd19 1.620 vd19 60.3 r20+17.6 fI 61.174 phi I 0.00686 phi I 0.01074 phi II -0.02493 phi II -0.03789 phi III -0.01499 phi III 0.02787 phi III 0.04230 phi III 0.05515 phi III 0.02749 wherein r1, r2, ... r20 are in millimeters the radii of curvature of successive boundary surfaces of lens elements, d1, d2, ... d19 are in millimeters the center distances between successive boundary surfaces of lens elements, nd1, nd3, ... nd19 are the indices of refraction of media having center thicknesses d1, d3, ... d19, respectively, vd1, vd3, ... vd19 are the Abbe numbers of lens elements having center thicknesses d1, d3, ... d19, fI is the focal length of the first lens unit, phi 10 and phi 11 are, respectively, the refractive powers of the forward and rear surfaces of said biconvex lens element of said third lens component, phi I and phi I are, respectively, the refractive powers of said second lens component, phi II and phi II are, respectively, the refractive powers of said third and fourth lens components, wherein phi III and phi III are, respectively, the refractive powers of said meniscus and said biconvex lens element of said biconvex lens component, phi III and phi III are, respectively, the refractive powers of said biconvex lens component and said positive meniscus of said third lens unit, and phi III is the refractive power of said third lens unit.
Claim 5
Dependent Claim
533 words
A pancratic lens, which comprises a rear lens unit having a fixed focal length and a pancratic lens supplement having a continuously variable magnification factor and designed like a Galilean telescope, said pancratic lens supplement comprising a stationary, positive first lens unit, an axially displaceable, negative second lens unit succeeding said first lens unit, an axially displaceable, positive third lens unit succeeding said second lens unit and a stationary, negative fourth lens unit succeeding said third lens unit, said first lens unit consisting of a negative first lens component and a positive second lens component spaced behind said first lens component, said first and second lens components having focal lengths of about -420%fI and about 90%fI, respectively, where fI is the focal length of said first lens unit, said second lens unit consisting of third and fourth lens components, said third lens component consisting of a negative meniscus convexly curved toward the light-receiving side and consisting of a biconvex lens element and a biconcave lens element cemented to said biconvex lens element, said fourth lens component consisting of a biconcave lens element having almost equal sides, said third lens unit consisting of a biconvex lens component and a positive meniscus having about the same refractive power, said fourth lens unit consisting of a single biconcave lens element having a less steeply curved surface facing said third lens unit, said second and third lens units being adjustable to a first position in which said lens has a smallest focal length fmin, and to a second position in which said lens has a largest focal length fmax, said pancratic lens supplement further comprising means for displacing said second and third lens units to said first and second positions through a first range in accordance with a first function selected to maintain the object focal plane of the lens constant anD through a second range in accordance with a second function selected to vary the distance from the object focal plane to said first lens unit, said rear lens unit constitutes an extended triplet consisting of a biconvex lens element, a biconcave lens element and two positive single lens elements, said biconcave lens element of said rear lens unit has equal sides and meets the condition: d24>d25>d26 wherein d25 is the center thickness of said biconcave lens element and d24 and d26 are the vertex distances from said biconcave lens element to adjacent lens elements, said rear lens unit has the following data: r23+17.8 d23 4.2/nd23 1.570 vd23 49.5 r24-49.7 d24 3.5 r25-16.5 d25 2.4/nd25 1.847 vd25 23.8 fV 17.769 r26+16.5 d26 1.35 r27-585 d27 3.8/nd27 1.569 vd27 63.1 r28-12.4 d28 0.2 r29+18.9 d29 3.1/nd29 1.620 vd29 60.3 r30-23.3 in which r23, r24, ... r30 are in millimeters the radii of curvature of successive boundary surfaces of lens elements, d23, d25, ... d29 are in millimeters the center distances between successive boundary surfaces of lens elements, nd23, nd25, ... nd29 are the indices of refraction of media having center thicknesses d23, d25, ... d29, respectively, vd23, vd25, ... vd29 are the Abbe numbers of lens elements having center thicknesses d23, d25, ... d29 and fV is the focal length of said rear lens unit in millimeters.
Claim 6
Dependent Claim
533 words
A pancratic lens, which comprises a rear lens unit having a fixed focal length and a pancratic lens supplement having a continuously variable magnification factor and designed like a Galilean telescope, said pancratic lens supplement comprising a stationary, positive first lens unit, an axially displaceable, negative second lens unit succeeding said first lens unit, an axially displaceable, positive third lens unit succeeding said second lens unit and a stationary, negative fourth lens unit succeeding said third lens unit, said first lens unit consisting of a negative first lens component and a positive second lens component spaced behind said first lens component, said first and second lens components having focal lengths of about -420%fI and about 90%fI, respectively, where fI is the focal length of said first lens unit, said second lens unit consisting of third and fourth lens components, said third lens component consisting of a negative meniscus convexly curved toward the light-receiving side and consisting of a biconvex lens element and a biconcave lens element cemented to said biconvex lens element, said fourth lens component consisting of a biconcave lens element having almost equal sides, said third lens unit consisting of a biconvex lens component and a positive meniscus having about the same refractive power, said fourth lens unit consisting of a single biconcave lens element having a less steeply curved surface facing said third lens unit, said second and third lens units being adjustable to a first position in which said lens has a smallest focal length fmin, and to a second position in which said lens has a largest focal length fmax, said pancratic lens supplement further comprising means for displacing said second and third lens units to said first and second positions through a first range in accordance with a first function selected to maintain the object focal plane of the lens constant anD through a second range in accordance with a second function selected to vary the distance from the object focal plane to said first lens unit, said rear lens unit constitutes an extended triplet consisting of a biconvex lens element, a biconcave lens element and two positive single lens elements, said biconcave lens element of said rear lens unit has equal sides and meets the condition: d24>d25>d26 wherein d25 is the center thickness of said biconcave lens element and d24 and d26 are the vertex distances from said biconcave lens element to adjacent lens elements, said rear lens unit has the following data: r23+17.8 d23 4.2/nd23 1.570 vd23 49.5 r24-49.7 d24 3.5 r25-16.5 d25 2.4/nd25 1.847 vd25 23.8 fV 17.769 r26+16.5 d26 1.35 r27-585 d27 3.8/nd27 1.569 vd27 63.1 r28-12.4 d28 0.2 r29+18.9 d29 3.1/nd29 1.620 vd29 60.3 r30-23.3 in which r23, r24, ... r30 are in millimeters the radii of curvature of successive boundary surfaces of lens elements, d23, d25, ... d29 are in millimeters the center distances between successive boundary surfaces of lens elements, nd23, nd25, ... nd29 are the indices of refraction of media having center thicknesses d23, d25, ... d29, respectively, vd23, vd25, ... vd29 are the Abbe numbers of lens elements having center thicknesses d23, d25, ... d29 and fV is the focal length of said rear lens unit in millimeters.
Claim 7
Dependent Claim
522 words
A pancratic lens, which comprises a rear lens unit having a fixed focal length and a pancratic lens supplement having a continuously variable magnification factor and designed like a Galilean telescope, said pancratic lens supplement comprising a stationary, positive first lens unit, an axially displaceable, negative second lens unit succeeding said first lens unit, an axially displaceable, positive third lens unit succeeding said second lens unit, and a stationary, negative fourth lens unit succeeding said third lens unit, said first lens unit consisting of a negative first lens component and a positive second lens component spaced behind said first lens component, said first and second lens components having focal lengths of about -420%fI and about 90%fI, respectively, where fI is the focal length of said first lens unit, said second lens unit consisting of third and fourth lens components, said third lens component consisting of a negative meniscus convexly curved toward the light-receiving side and consisting of a biconvex lens element and a biconcave lens element cemented to said biconvex lens element, said fourth lens component consisting of a biconcave lens element having almost equal sides, said third lens unit consisting of a biconvex lens component and a positive meniscus having about the same refractive power, said fourth lens unit consisting of a single biconcave lens element having a less steeply curved surface facing said third lens unit, said second and third lens units being adjustable to a first position in which said lens has a smallest focal length fmin, and to a second position in which said lens has a largest focal length fmax, said pancratic lens supplement further comprising means for displacing said second and third lens units to said first and second positions through a first range in accordance with a first function selected to maintain the object focal plane of the lens constant and through a second range in accordance with a second function selected to vary the distance from the object focal plane to said first lens unit, said rear lens unit constitutes an extended triplet consisting of a biconvex lens element, a biconcave lens element and two positive single lens elements, said biconcave lens element of said rear lens unit has equal sides and meets the condition: d24>d25>d26 wherein d25 is the center thickness of said biconcave lens element and d24 and d26 are the vertex distances from said biconcave lens element to adjacent lens elements, r23+20.0 d23 4.2/nd23 1.569 vd23 56.1 r24-49.7 d24 3.5 r25-19.1 d25 2.8/nd25 1.847 vd25 23.8 r26+19.1 d26 1.35 r27-585 d273.8/nd27 1.569 vd27 63.1 r28-12.4 d28 0.2 r29+16.4 d29 3.1/nd29 1.641 vd29 60.1 r30-45.9 in which r23, r24, ... r30 are in millimeters the radii of curvature of successive boundary surfaces of lens elements, d23, d25, ... d29 are in millimeters the center distances between successive boundary surfaces of lens elements, nd23, nd25, ... nd29 are the indices of refraction of media having center thicknesses d23, d25, ... d29, respectively, vd23, vd25, ... vd29 are the Abbe numbers of lens elements having center thicknesses d23, d25, ... d29 and fV is the focal length of said rear lens unit in millimeters.
Claim 8
Dependent Claim
522 words
A pancratic lens, which comprises a rear lens unit having a fixed focal length and a pancratic lens supplement having a continuously variable magnification factor and designed like a Galilean telescope, said pancratic lens supplement comprising a stationary, positive first lens unit, an axially displaceable, negative second lens unit succeeding said first lens unit, an axially displaceable, positive third lens unit succeeding said second lens unit, and a stationary, negative fourth lens unit succeeding said third lens unit, said first lens unit consisting of a negative first lens component and a positive second lens component spaced behind said first lens component, said first and second lens components having focal lengths of about -420%fI and about 90%fI, respectively, where fI is the focal length of said first lens unit, said second lens unit consisting of third and fourth lens components, said third lens component consisting of a negative meniscus convexly curved toward the light-receiving side and consisting of a biconvex lens element and a biconcave lens element cemented to said biconvex lens element, said fourth lens component consisting of a biconcave lens element having almost equal sides, said third lens unit consisting of a biconvex lens component and a positive meniscus having about the same refractive power, said fourth lens unit consisting of a single biconcave lens element having a less steeply curved surface facing said third lens unit, said second and third lens units being adjustable to a first position in which said lens has a smallest focal length fmin, and to a second position in which said lens has a largest focal length fmax, said pancratic lens supplement further comprising means for displacing said second and third lens units to said first and second positions through a first range in accordance with a first function selected to maintain the object focal plane of the lens constant and through a second range in accordance with a second function selected to vary the distance from the object focal plane to said first lens unit, said rear lens unit constitutes an extended triplet consisting of a biconvex lens element, a biconcave lens element and two positive single lens elements, said biconcave lens element of said rear lens unit has equal sides and meets the condition: d24>d25>d26 wherein d25 is the center thickness of said biconcave lens element and d24 and d26 are the vertex distances from said biconcave lens element to adjacent lens elements, r23+20.0 d23 4.2/nd23 1.569 vd23 56.1 r24-49.7 d24 3.5 r25-19.1 d25 2.8/nd25 1.847 vd25 23.8 r26+19.1 d26 1.35 r27-585 d273.8/nd27 1.569 vd27 63.1 r28-12.4 d28 0.2 r29+16.4 d29 3.1/nd29 1.641 vd29 60.1 r30-45.9 in which r23, r24, ... r30 are in millimeters the radii of curvature of successive boundary surfaces of lens elements, d23, d25, ... d29 are in millimeters the center distances between successive boundary surfaces of lens elements, nd23, nd25, ... nd29 are the indices of refraction of media having center thicknesses d23, d25, ... d29, respectively, vd23, vd25, ... vd29 are the Abbe numbers of lens elements having center thicknesses d23, d25, ... d29 and fV is the focal length of said rear lens unit in millimeters.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |