1. A collapsible T-handle for use in cleaning the barrel of a firearm having a bore of a fixed internal diameter, said collapsible T-handle comprising:
a longitudinal body having first and second spaced-apart ears at a first end thereof, an attachment portion at a second and opposite end thereof, and a longitudinal well terminating at said spaced-apart ears; and
a handle disposed on a pivot pin between said first and second ears;
wherein said handle is rotatable on said pivot pin between a closed position wherein a portion of said handle occupies said longitudinal well and an open position wherein the longitudinal axis of said handle is substantially transverse to the longitudinal axis of said body; and wherein the outer diameter of said T-handle when in said closed position is less than the bore diameter of the firearm to be cleaned.
2. The collapsible T-handle of claim 1 wherein the thickness of each of said first and second ears is greater than the thickness of a wall of said longitudinal well.
3. The collapsible T-handle of claim 1 wherein said tool can withstand without failure a pull force on said handle of at least about 100 pounds when opposed by a like drag force on said longitudinal body.
4. The collapsible T-handle of claim 1 wherein the maximum overall outside diameter is less than about 0.30 inch.
5. A method for cleaning the bore of a firearm, comprising the steps of:
providing a tool having a longitudinal body having first and second spaced-apart ears at a first end thereof, an attachment portion at a second and opposite end thereof, and a longitudinal well terminating at said spaced-apart ears, and a handle disposed on a pivot pin between said first and second ears, wherein said handle is rotatable on said pivot pin between a closed position wherein a portion of said handle occupies said longitudinal well and an open position wherein the longitudinal axis of said handle is substantially transverse to the longitudinal axis of said body;
pivoting said handle in a first direction to place said tool in said closed position;
inserting said tool in said closed position into said firearm bore;
attaching a cleaning tool to said attachment portion;
passing said tool through said bore;
pivoting said handle in a second direction to place said tool in said open position; and
pulling on said handle to cause said cleaning tool to be passed through said bore.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A zoom lens system, in order from the object side to the image side, comprising a first lens unit having negative optical power, a second lens unit having positive optical power and a third lens unit having positive optical power, wherein
the first lens unit, in order from the object side to the image side, consists of a first lens element that has a concave surface at least on the image side and that has negative optical power and a second lens element that has a convex surface at least on the object side and that has positive optical power,
the second lens unit, in order from the object side to the image side, comprises a third lens element being one single lens element, a cemented lens element fabricated by cementing a fourth lens element and a fifth lens element having optical power of mutually different signs, and a sixth lens element being one single lens element,
in zooming from a wide-angle limit to a telephoto limit, all of the first lens unit, the second lens unit and the third lens unit move along an optical axis, and
the following conditions (1), (I-2) and (5) are satisfied:
5.0<\u03b1iW<20.0\u2003\u2003(1)
n11\u22671.9\u2003\u2003(I-2)
0.1<(n11\u22121)\xb7(n12\u22121)\xb7d\xb7fW(r12\xb7r21)<0.3\u2003\u2003(5)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
\u03b1iW is an incident angle of a principal ray to an image sensor at a maximum image height at a wide-angle limit (defined as positive when the principal ray is incident on a light acceptance surface of the image sensor in a state of departing from the optical axis),
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
2. The zoom lens system as claimed in claim 1, satisfying the following condition (I-3):
0.8<(n11\u22121)2<1.5\u2003\u2003(I-3)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
n11 is a refractive index of the first lens element to the d-line,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
3. The zoom lens system as claimed in claim 1, satisfying the following condition (I-4):
0.75<(n11\u22121)\xb7fWr12<1.2\u2003\u2003(I-4)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
r12 is a radius of curvature of the image side surface of the first lens element,
n11 is a refractive index of the first lens element to the d-line,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
4. The zoom lens system as claimed in claim 1, satisfying the following condition (6):
0.0001<(n11\u22121)\xb7(n12\u22121)\xb7d2\xb7fW(r12\xb7r21\xb7ft)<0.04\u2003\u2003(6)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
5. The zoom lens system as claimed in claim 1, satisfying the following condition (9):
2.4<|fG1|fW<4.0\u2003\u2003(9)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fG1 is a composite focal length of the first lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
6. The zoom lens system as claimed in claim 1, satisfying the following condition (10):
1.85<fG2fW<3.0\u2003\u2003(10)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fG2 is a composite focal length of the second lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
7. The zoom lens system as claimed in claim 1, satisfying the following condition (11):
2.5<fG3fW<6.0\u2003\u2003(11)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fG3 is a composite focal length of the third lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
8. The zoom lens system as claimed in claim 1, satisfying the following condition (12):
1.0<|fL1|fW<2.5\u2003\u2003(12)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL1 is a focal length of the first lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
9. The zoom lens system as claimed in claim 1, satisfying the following condition (13):
2.0<fL2fW<5.0\u2003\u2003(13)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL2 is a focal length of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
10. The zoom lens system as claimed in claim 1, satisfying the following condition (14):
0.4<|fL1||fG1|<0.8\u2003\u2003(14)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL1 is a focal length of the first lens element,
fG1 is a composite focal length of the first lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
11. The zoom lens system as claimed in claim 1, satisfying the following condition (15):
0.85<fL2|fG1|<2.0\u2003\u2003(15)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL2 is a focal length of the second lens element,
fG1 is a composite focal length of the first lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
12. The zoom lens system as claimed in claim 1, satisfying the following condition (16):
1.9<fL2|fL1|<3.0\u2003\u2003(16)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL1 is a focal length of the first lens element,
fL2 is a focal length of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
13. The zoom lens system as claimed in claim 1, wherein the second lens unit moves in a direction perpendicular to the optical axis.
14. An imaging device capable of outputting an optical image of an object as an electric image signal, comprising:
a zoom lens system that forms the optical image of the object; and
an image sensor that converts the optical image formed by the zoom lens system into the electric image signal, wherein
in the zoom lens system,
the system, in order from the object side to the image side, comprises a first lens unit having negative optical power, a second lens unit having positive optical power and a third lens unit having positive optical power, wherein
the first lens unit, in order from the object side to the image side, consists of a first lens element that has a concave surface at least on the image side and that has negative optical power and a second lens element that has a convex surface at least on the object side and that has positive optical power,
the second lens unit, in order from the object side to the image side, comprises a third lens element being one single lens element, a cemented lens element fabricated by cementing a fourth lens element and a fifth lens element having optical power of mutually different signs, and a sixth lens element being one single lens element,
in zooming from a wide-angle limit to a telephoto limit, all of the first lens unit, the second lens unit and the third lens unit move along an optical axis, and
the following conditions (1), (I-2) and (5) are satisfied:
5.0<\u03b1iW<20.0\u2003\u2003(1)
n11\u22671.9\u2003\u2003(I-2)
0.1<(n11\u22121)\xb7(n12\u22121)\xb7d\xb7fW(r12\xb7r21)<0.3\u2003\u2003(5)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
\u03b1iW is an incident angle of a principal ray to an image sensor at a maximum image height at a wide-angle limit (defined as positive when the principal ray is incident on a light acceptance surface of the image sensor in a state of departing from the optical axis),
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
15. A camera for converting an optical image of an object into an electric image signal and then performing at least one of displaying and storing of the converted image signal, comprising
an imaging device having a zoom lens system that forms the optical image of the object and an image sensor that converts the optical image formed by the zoom lens system into the electric image signal, wherein
in the zoom lens system,
the system, in order from the object side to the image side, comprises a first lens unit having negative optical power, a second lens unit having positive optical power and a third lens unit having positive optical power, wherein
the first lens unit, in order from the object side to the image side, consists of a first lens element that has a concave surface at least on the image side and that has negative optical power and a second lens element that has a convex surface at least on the object side and that has positive optical power,
the second lens unit, in order from the object side to the image side, comprises a third lens element being one single lens element, a cemented lens element fabricated by cementing a fourth lens element and a fifth lens element having optical power of mutually different signs, and a sixth lens element being one single lens element,
in zooming from a wide-angle limit to a telephoto limit, all of the first lens unit, the second lens unit and the third lens unit move along an optical axis, and
the following conditions (1), (I-2) and (5) are satisfied:
5.0<\u03b1iW<20.0\u2003\u2003(1)
n11\u22671.9\u2003\u2003(I-2)
0.1<(n11\u22121)\xb7(n12\u22121)\xb7d\xb7fW(r12\xb7r21)<0.3\u2003\u2003(5)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
\u03b1iW is an incident angle of a principal ray to an image sensor at a maximum image height at a wide-angle limit (defined as positive when the principal ray is incident on a light acceptance surface of the image sensor in a state of departing from the optical axis),
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
16. A zoom lens system, in order from the object side to the image side, comprising a first lens unit having negative optical power, a second lens unit having positive optical power and a third lens unit having positive optical power, wherein
the first lens unit, in order from the object side to the image side, consists of a first lens element that has a concave surface at least on the image side and that has negative optical power and a second lens element that has a convex surface at least on the object side and that has positive optical power,
the second lens unit, in order from the object side to the image side, comprises a third lens element being one single lens element, a cemented lens element fabricated by cementing a fourth lens element and a fifth lens element having optical power of mutually different signs, and a sixth lens element being one single lens element,
in zooming from a wide-angle limit to a telephoto limit, all of the first lens unit, the second lens unit and the third lens unit move along an optical axis, and
the following conditions (1), (II-2) and (5) are satisfied:
5.0<\u03b1iW<20.0\u2003\u2003(1)
(n11\u22121)\xb7(n12\u22121)\u22670.84\u2003\u2003(II-2)
0.1<(n11\u22121)\xb7(n12\u22121)\xb7d\xb7fW(r12\xb7r21)<0.3\u2003\u2003(5)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
\u03b1iW is an incident angle of a principal ray to an image sensor at a maximum image height at a wide-angle limit (defined as positive when the principal ray is incident on a light acceptance surface of the image sensor in a state of departing from the optical axis),
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
17. The zoom lens system as claimed in claim 16, satisfying the following condition (6):
0.0001<(n11\u22121)\xb7(n12\u22121)\xb7d2\xb7fW(r12\xb7r21\xb7ft)<0.04\u2003\u2003(6)
(wherein, 3.2<fTfW and \u03c9W>35) where,
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
18. The zoom lens system as claimed in claim 16, satisfying the following condition (9):
2.4<|fG1|fW<4.0\u2003\u2003(9)
(wherein, 3.2<fTfW and \u03c9W>35) where,
fG1 is a composite focal length of the first lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
19. The zoom lens system as claimed in claim 16, satisfying the following condition (10):
1.85<fG2fW<3.0\u2003\u2003(10)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fG2 is a composite focal length of the second lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
20. The zoom lens system as claimed in claim 16, satisfying the following condition (11):
2.5<fG3fW<6.0\u2003\u2003(11)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fG3 is a composite focal length of the third lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
21. The zoom lens system as claimed in claim 16, satisfying the following condition (12):
1.0<|fL1|fW<2.5\u2003\u2003(12)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL1 is a focal length of the first lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
22. The zoom lens system as claimed in claim 16, satisfying the following condition (13):
2.0<fL2fW<5.0\u2003\u2003(13)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL2 is a focal length of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
23. The zoom lens system as claimed in claim 16, satisfying the following condition (14):
0.4<|fL1||fG1|<0.8\u2003\u2003(14)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL1 is a focal length of the first lens element,
fG1 is a composite focal length of the first lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
24. The zoom lens system as claimed in claim 16, satisfying the following condition (15):
0.85<fL2|fG1|<2.0\u2003\u2003(15)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL2 is a focal length of the second lens element,
fG1 is a composite focal length of the first lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
25. The zoom lens system as claimed in claim 16, satisfying the following condition (16):
1.9<fL2|fL1|<3.0\u2003\u2003(16)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL1 is a focal length of the first lens element,
fL2 is a focal length of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
26. The zoom lens system as claimed in claim 16, wherein the second lens unit moves in a direction perpendicular to the optical axis.
27. An imaging device capable of outputting an optical image of an object as an electric image signal, comprising:
a zoom lens system that forms the optical image of the object; and
an image sensor that converts the optical image formed by the zoom lens system into the electric image signal, wherein
in the zoom lens system,
the system, in order from the object side to the image side, comprises a first lens unit having negative optical power, a second lens unit having positive optical power and a third lens unit having positive optical power, wherein
the first lens unit, in order from the object side to the image side, consists of a first lens element that has a concave surface at least on the image side and that has negative optical power and a second lens element that has a convex surface at least on the object side and that has positive optical power,
the second lens unit, in order from the object side to the image side, comprises a third lens element being one single lens element, a cemented lens element fabricated by cementing a fourth lens element and a fifth lens element having optical power of mutually different signs, and a sixth lens element being one single lens element,
in zooming from a wide-angle limit to a telephoto limit, all of the first lens unit, the second lens unit and the third lens unit move along an optical axis, and
the following conditions (1), (II-2) and (5) are satisfied:
5.0<\u03b1iW<20.0\u2003\u2003(1)
(n11\u22121)\xb7(n12\u22121)\u22670.84\u2003\u2003(II-2)
0.1<(n11\u22121)\xb7(n12\u22121)\xb7d\xb7fW(r12\xb7r21)<0.3\u2003\u2003(5)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
\u03b1iW is an incident angle of a principal ray to an image sensor at a maximum image height at a wide-angle limit (defined as positive when the principal ray is incident on a light acceptance surface of the image sensor in a state of departing from the optical axis),
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
28. A camera for converting an optical image of an object into an electric image signal and then performing at least one of displaying and storing of the converted image signal, comprising
an imaging device having a zoom lens system that forms the optical image of the object and an image sensor that converts the optical image formed by the zoom lens system into the electric image signal, wherein
in the zoom lens system,
the system, in order from the object side to the image side, comprises a first lens unit having negative optical power, a second lens unit having positive optical power and a third lens unit having positive optical power, wherein
the first lens unit, in order from the object side to the image side, consists of a first lens element that has a concave surface at least on the image side and that has negative optical power and a second lens element that has a convex surface at least on the object side and that has positive optical power,
the second lens unit, in order from the object side to the image side, comprises a third lens element being one single lens element, a cemented lens element fabricated by cementing a fourth lens element and a fifth lens element having optical power of mutually different signs, and a sixth lens element being one single lens element,
in zooming from a wide-angle limit to a telephoto limit, all of the first lens unit, the second lens unit and the third lens unit move along an optical axis, and
the following conditions (1), (II-2) and (5) are satisfied:
5.0<\u03b1iW<20.0\u2003\u2003(1)
(n11\u22121)\xb7(n12\u22121)\u22670.84\u2003\u2003(II-2)
0.1<(n11\u22121)\xb7(n12\u22121)\xb7d\xb7fW(r12\xb7r21)<0.3\u2003\u2003(5)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
\u03b1iW is an incident angle of a principal ray to an image sensor at a maximum image height at a wide-angle limit (defined as positive when the principal ray is incident on a light acceptance surface of the image sensor in a state of departing from the optical axis),
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
29. A zoom lens system, in order from the object side to the image side, comprising a first lens unit having negative optical power, a second lens unit having positive optical power and a third lens unit having positive optical power, wherein
the first lens unit, in order from the object side to the image side, consists of a first lens element that has a concave surface at least on the image side and that has negative optical power and a second lens element that has a convex surface at least on the object side and that has positive optical power,
the second lens unit, in order from the object side to the image side, comprises a third lens element being one single lens element, a cemented lens element fabricated by cementing a fourth lens element and a fifth lens element having optical power of mutually different signs, and a sixth lens element being one single lens element,
in zooming from a wide-angle limit to a telephoto limit, all of the first lens unit, the second lens unit and the third lens unit move along an optical axis, and
the following conditions (1), (III-2) and (5) are satisfied:
5.0<\u03b1iW<20.0\u2003\u2003(1)
n12\u22672.1\u2003\u2003(III-2)
0.1<(n11\u22121)\xb7(n12\u22121)\xb7d\xb7fW(r12\xb7r21)<0.3\u2003\u2003(5)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
\u03b1iW is an incident angle of a principal ray to an image sensor at a maximum image height at a wide-angle limit (defined as positive when the principal ray is incident on a light acceptance surface of the image sensor in a state of departing from the optical axis),
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
30. The zoom lens system as claimed in claim 29, satisfying the following condition (III-3):
0.8<(n12\u22121)2<1.5\u2003\u2003(III-3)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
n12 is a refractive index of the second lens element to the d-line,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
31. The zoom lens system as claimed in claim 29, satisfying the following condition (III-4):
0.4<(n12\u22121)\xb7fWr21<0.7\u2003\u2003(III-4)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
r21 is a radius of curvature of the object side surface of the second lens element,
n12 is a refractive index of the second lens element to the d-line,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
32. The zoom lens system as claimed in claim 29, satisfying the following condition (6):
0.0001<(n11\u22121)\xb7(n12\u22121)\xb7d2fW(r12\xb7r21\xb7ft)<0.04\u2003\u2003(6)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
33. The zoom lens system as claimed in claim 29, satisfying the following condition (9):
2.4<|fG1|fW<4.0\u2003\u2003(9)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fG1 is a composite focal length of the first lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
34. The zoom lens system as claimed in claim 29, satisfying the following condition (10):
1.85<fG2fW<3.0\u2003\u2003(10)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fG2 is a composite focal length of the second lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
35. The zoom lens system as claimed in claim 29, satisfying the following condition (11):
2.5<fG3fW<6.0\u2003\u2003(11)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fG3 is a composite focal length of the third lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
36. The zoom lens system as claimed in claim 29, satisfying the following condition (12):
1.0<|fL1|fW<2.5\u2003\u2003(12)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL1 is a focal length of the first lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
37. The zoom lens system as claimed in claim 29, satisfying the following condition (13):
2.0<fL2fW<5.0\u2003\u2003(13)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL2 is a focal length of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
38. The zoom lens system as claimed in claim 29, satisfying the following condition (14):
0.4<|fL1||fG1|<0.8\u2003\u2003(14)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL1 is a focal length of the first lens element,
fG1 is a composite focal length of the first lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
39. The zoom lens system as claimed in claim 29, satisfying the following condition (15):
0.85<fL2|fG1|<2.0\u2003\u2003(15)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL2 is a focal length of the second lens element,
fG1 is a composite focal length of the first lens unit,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
40. The zoom lens system as claimed in claim 29, satisfying the following condition (16):
1.9<fL2|fL1|<3.0\u2003\u2003(16)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
fL1 is a focal length of the first lens element,
fL2 is a focal length of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
41. The zoom lens system as claimed in claim 29, wherein the second lens unit moves in a direction perpendicular to the optical axis.
42. An imaging device capable of outputting an optical image of an object as an electric image signal, comprising:
a zoom lens system that forms the optical image of the object; and
an image sensor that converts the optical image formed by the zoom lens system into the electric image signal, wherein
in the zoom lens system,
the system, in order from the object side to the image side, comprises a first lens unit having negative optical power, a second lens unit having positive optical power and a third lens unit having positive optical power, wherein
the first lens unit, in order from the object side to the image side, consists of a first lens element that has a concave surface at least on the image side and that has negative optical power and a second lens element that has a convex surface at least on the object side and that has positive optical power,
the second lens unit, in order from the object side to the image side, comprises a third lens element being one single lens element, a cemented lens element fabricated by cementing a fourth lens element and a fifth lens element having optical power of mutually different signs, and a sixth lens element being one single lens element,
in zooming from a wide-angle limit to a telephoto limit, all of the first lens unit, the second lens unit and the third lens unit move along an optical axis, and
the following conditions (1), (III-2) and (5) are satisfied:
5.0<\u03b1iW<20.0\u2003\u2003(1)
n12\u22672.1\u2003\u2003(III-2)
0.1<(n11\u22121)\xb7(n12\u22121)\xb7d\xb7fW(r12\xb7r21)<0.3\u2003\u2003(5)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
\u03b1iW is an incident angle of a principal ray to an image sensor at a maximum image height at a wide-angle limit (defined as positive when the principal ray is incident on a light acceptance surface of the image sensor in a state of departing from the optical axis),
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.
43. A camera for converting an optical image of an object into an electric image signal and then performing at least one of displaying and storing of the converted image signal, comprising
an imaging device having a zoom lens system that forms the optical image of the object and an image sensor that converts the optical image formed by the zoom lens system into the electric image signal, wherein
in the zoom lens system,
the system, in order from the object side to the image side, comprises a first lens unit having negative optical power, a second lens unit having positive optical power and a third lens unit having positive optical power, wherein
the first lens unit, in order from the object side to the image side, consists of a first lens element that has a concave surface at least on the image side and that has negative optical power and a second lens element that has a convex surface at least on the object side and that has positive optical power,
the second lens unit, in order from the object side to the image side, comprises a third lens element being one single lens element, a cemented lens element fabricated by cementing a fourth lens element and a fifth lens element having optical power of mutually different signs, and a sixth lens element being one single lens element,
in zooming from a wide-angle limit to a telephoto limit, all of the first lens unit, the second lens unit and the third lens unit move along an optical axis, and
the following conditions (1), (III-2) and (5) are satisfied:
5.0<\u03b1iW<20.0\u2003\u2003(1)
n12\u22672.1\u2003\u2003(III-2)
0.1<(n11\u22121)\xb7(n12\u22121)\xb7d\xb7fW(r12\xb7r21)<0.3\u2003\u2003(5)
(wherein, 3.2<fTfW and \u03c9W>35)
where,
\u03b1iW is an incident angle of a principal ray to an image sensor at a maximum image height at a wide-angle limit (defined as positive when the principal ray is incident on a light acceptance surface of the image sensor in a state of departing from the optical axis),
n11 is a refractive index of the first lens element to the d-line,
n12 is a refractive index of the second lens element to the d-line,
r12 is a radius of curvature of the image side surface of the first lens element,
r21 is a radius of curvature of the object side surface of the second lens element,
d is an optical axial distance between the image side surface of the first lens element and the object side surface of the second lens element,
\u03c9W is a half view angle (\xb0) at a wide-angle limit,
fT is a focal length of the entire system at a telephoto limit, and
fW is a focal length of the entire system at a wide-angle limit.