US5995295A
Expired / Lapsed
US
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Lens system
Assignee: Olympus Corp
•
Filing: 1996-12-12
•
Granted: 1999-11-30
•
Expires: 2016-12-12
Abstract
Abstract A lens system which is composed of at least one homogeneous lens element and at least one radial type gradient index lens element, to be used as a combination lens system or an image pickup lens system, and configured to favorably correct chromatic aberration, etc. by selecting an adequate value for a coefficient representing an Abbe's number.
Inventors
- 👤 Toshiyuki Nagaoka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:34
CPC Classifications
G; G02; G02B; G02B13/00; G02B13/001; G02B13/0015; G02B13/002; G02B13/0025; G02B13/003; G02B13/0045; G02B13/0055; G02B13/006; G02B13/009; G02B3/00; G02B3/0087
Claims Analysis
Total Claims: 44
Claim 1
Independent Claim
217 words
A combination lens system comprising: at least one homogeneous lens element; and at least one radial type gradient index lens element having refractive indices distributed from an optical axis in a radial direction, wherein at least one surface of said radial type gradient index lens element is partially or entirely planar and wherein said homogeneous lens element satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula; and said combination lens system satisfying the following condition (10): N.sub.00d >1.55 (10) wherein the reference symbol N 00d represents a refractive index of said gradient index lens element on the optical axis for the d-line.
Claim 2
Dependent Claim
217 words
A combination lens system comprising: at least one homogeneous lens element; and at least one radial type gradient index lens element having refractive indices distributed from an optical axis in a radial direction, wherein at least one surface of said radial type gradient index lens element is partially or entirely planar and wherein said homogeneous lens element satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula; and said combination lens system satisfying the following condition (10): N.sub.00d >1.55 (10) wherein the reference symbol N 00d represents a refractive index of said gradient index lens element on the optical axis for the d-line.
Claim 3
Dependent Claim
129 words
A lens system to be used as an image pickup lens system consisting of a homogeneous lens element having a negative refractive power; and a radial type gradient index lens element having refractive indices distributed from an optical axis in a radial direction, wherein said lens system satisfies the following condition (21): -0.5<1/V.sub.10 <0.015 (21) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 10d , N 10F and N 10C represent distribution coefficients of the second order for the d-line, F-line and C-line respectively when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 4
Dependent Claim
129 words
A lens system to be used as an image pickup lens system consisting of a homogeneous lens element having a negative refractive power; and a radial type gradient index lens element having refractive indices distributed from an optical axis in a radial direction, wherein said lens system satisfies the following condition (21): -0.5<1/V.sub.10 <0.015 (21) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 10d , N 10F and N 10C represent distribution coefficients of the second order for the d-line, F-line and C-line respectively when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 5
Dependent Claim
34 words
A lens system consisting of: a homogeneous lens element having a negative refractive power; and a gradient index lens element having a positive refractive power, wherein said homogeneous lens element has a meniscus shape.
Claim 6
Dependent Claim
34 words
A lens system consisting of: a homogeneous lens element having a negative refractive power; and a gradient index lens element having a positive refractive power, wherein said homogeneous lens element has a meniscus shape.
Claim 7
Dependent Claim
26 words
A lens system according to claim 3, said homogeneous lens element and said gradient index lens element are arranged from an object side in this order.
Claim 8
Dependent Claim
26 words
A lens system consisting of: a negative homogeneous lens element; and a positive gradient index lens element, wherein said homogeneous lens element has a biconcave shape.
Claim 9
Dependent Claim
26 words
A lens system consisting of: a negative homogeneous lens element; and a positive gradient index lens element, wherein said homogeneous lens element has a biconcave shape.
Claim 10
Dependent Claim
41 words
A lens system according to claim 2, 3, or 5 satisfying the following condition (10): N.sub.00d >1.55 (10) wherein the reference symbol N 00d represents a refractive index of said gradient index lens element on the optical axis for the d-line.
Claim 11
Dependent Claim
22 words
A lens system according to claim 2, 3, or 5 wherein said gradient index lens element has thickness not exceeding 40 mm.
Claim 12
Dependent Claim
26 words
A lens system according to claim 5, said homogeneous lens element and said gradient index lens element are arranged from an object side in this order.
Claim 13
Dependent Claim
194 words
A combination lens system comprising: at least one homogeneous lens element, and at least one radial type gradient index lens element having refractive indices distributed from an optical axis in a radial direction, wherein at least one surface of said radial type gradient index lens element is partially or entirely planar and wherein said homogeneous lens element satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i-1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.10 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively when the refractive index distribution of said gradient index lens element is expressed by a square formula; and said gradient index lens element has a thickness not exceeding 40 mm.
Claim 14
Dependent Claim
194 words
A combination lens system comprising: at least one homogeneous lens element, and at least one radial type gradient index lens element having refractive indices distributed from an optical axis in a radial direction, wherein at least one surface of said radial type gradient index lens element is partially or entirely planar and wherein said homogeneous lens element satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i-1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.10 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively when the refractive index distribution of said gradient index lens element is expressed by a square formula; and said gradient index lens element has a thickness not exceeding 40 mm.
Claim 15
Dependent Claim
19 words
A lens system according to claim 1, or 9 wherein said homogeneous lens element has a negative refractive power.
Claim 16
Dependent Claim
42 words
A lens system according to claim 1, 2, 5, 6 or 9 wherein an entire area of at least one surface of said homogeneous lens element or a partial area of at least one surface of said homogeneous lens element is planar.
Claim 17
Dependent Claim
52 words
A lens system according to claim 1, 2, 3, 5 or 9 wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is cemented or kept to or in close contact with a portion of said homogeneous lens element.
Claim 18
Dependent Claim
55 words
A lens system according to claim 1, 2, 3, 5, or 9 wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar is cemented or kept to or close contact with a portion of said homogeneous lens element by way of a spacer.
Claim 19
Dependent Claim
49 words
A lens system according to claim 1, 2, 3, 5, or 9 satisfying the following condition (3): 0.1<t.sub.G /f.sub.T <7 (3) wherein the reference symbol t G represents thickness of said gradient index lens element and the reference symbol f T designates a focal length of said lens system.
Claim 20
Dependent Claim
17 words
A lens system according to claim 9, wherein said homogeneous lens element has a negative refractive power.
Claim 21
Dependent Claim
34 words
A lens system according to claim 2, 10, 15 or 8 satisfying the following condition (29): 1/ν.sub.h <0.03 (29) wherein the reference symbol ν h represents an Abbe's number of said homogeneous lens element.
Claim 22
Dependent Claim
17 words
An image pickup system according to claim 1, 2, 3 5 or 9 comprising said lens system.
Claim 23
Dependent Claim
85 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element.
Claim 24
Dependent Claim
85 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element.
Claim 25
Dependent Claim
26 words
A lens system according to claim 18, said homogeneous lens element and said gradient index lens element are arranged from an object side in this order.
Claim 26
Dependent Claim
90 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element by way of a spacer, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element.
Claim 27
Dependent Claim
90 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element by way of a spacer, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element.
Claim 28
Dependent Claim
26 words
A lens system according to claim 20, said homogeneous lens element and said gradient index lens element are arranged from an object side in this order.
Claim 29
Dependent Claim
162 words
A lens system consisting of: a homogeneous lens element having a negative refractive power; and a gradient index lens element having a positive refractive power; and wherein said homogeneous lens element has a meniscus shape, wherein said system satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.10 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 30
Dependent Claim
162 words
A lens system consisting of: a homogeneous lens element having a negative refractive power; and a gradient index lens element having a positive refractive power; and wherein said homogeneous lens element has a meniscus shape, wherein said system satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.10 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 31
Dependent Claim
153 words
A lens system consisting of: a negative homogeneous lens element; and a positive gradient index lens element, wherein said homogeneous lens element has a biconcave shape, wherein said system satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.10 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 32
Dependent Claim
153 words
A lens system consisting of: a negative homogeneous lens element; and a positive gradient index lens element, wherein said homogeneous lens element has a biconcave shape, wherein said system satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.10 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 33
Dependent Claim
212 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element, wherein said system satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 34
Dependent Claim
212 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element, wherein said system satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 35
Dependent Claim
217 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element by way of a spacer, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element, wherein said system satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 36
Dependent Claim
217 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element by way of a spacer, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element, wherein said system satisfies the following condition (1): 1/V.sub.10 <1/ν.sub.h ( 1) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1 and the reference symbol ν h designates an Abbe's number of said homogeneous lens element: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 37
Dependent Claim
145 words
A lens system consisting of: a homogeneous lens element having a negative refractive power; and a gradient index lens element having a positive refractive power, wherein said homogeneous lens element has a meniscus shape, wherein said system satisfies the following condition (21): -0.5<1/V.sub.10 <0.015 (21) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 38
Dependent Claim
145 words
A lens system consisting of: a homogeneous lens element having a negative refractive power; and a gradient index lens element having a positive refractive power, wherein said homogeneous lens element has a meniscus shape, wherein said system satisfies the following condition (21): -0.5<1/V.sub.10 <0.015 (21) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 39
Dependent Claim
137 words
A lens system consisting of: a negative homogeneous lens element; and a positive gradient index lens element, wherein said homogeneous lens element has a biconcave shape, wherein said system satisfies the following condition (21): -0.5<1/V.sub.10 <0.015 (21) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 40
Dependent Claim
137 words
A lens system consisting of: a negative homogeneous lens element; and a positive gradient index lens element, wherein said homogeneous lens element has a biconcave shape, wherein said system satisfies the following condition (21): -0.5<1/V.sub.10 <0.015 (21) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 41
Dependent Claim
196 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element, wherein said system satisfies the following condition (21): -0.5<1/V.sub.10 <0.015 (21) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 42
Dependent Claim
196 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element, wherein said system satisfies the following condition (21): -0.5<1/V.sub.10 <0.015 (21) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 43
Dependent Claim
201 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element by way of a spacer, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element, wherein said system satisfies the following condition (21): -0.5<1/V.sub.10 <0.015 (21) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
Claim 44
Dependent Claim
201 words
A lens system comprising: at least one homogeneous lens element; and at least one gradient index lens element, wherein a partial or entire area of at least one surface of said gradient index lens element is planar and said planar area is in close contact with a portion of said homogeneous lens element by way of a spacer, and wherein said lens system is focused on an object located at an extremely short distance by varying an airspace reserved between said homogeneous lens element and said gradient index lens element, wherein said system satisfies the following condition (21): -0.5<1/V.sub.10 <0.015 (21) wherein the reference symbol V 10 represents a value which is given by the formula (c) shown below at i=1: V.sub.i0 =N.sub.i0d /(N.sub.i0F -N.sub.i0C) (i=1, 2, 3, . . . )(c) wherein the reference symbols N 00d , N 00F and N 00C represent refractive indices on an optical axis for the d-line, F-line and C-line, respectively, and the reference symbols N 10d , N 10F and N 10C designate distribution coefficients of the second order for the d-line, F-line and C-line, respectively, when the refractive index distribution of said gradient index lens element is expressed by a square formula.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-11-29 | 2003-05-31 | 2003-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-29 | 2007-05-31 | 2007-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-11-29 | 2011-05-31 | 2011-11-30 | $7700.00 | Window Closed / Lapsed |