JPWO2019220615A1 - Optical systems, optical instruments, and methods of manufacturing optical systems - Google Patents

Abstract

The optical system (LS) has a first lens group (G1) having a positive refractive power, a second lens group (G2) having a positive refractive power, and a negative refractive power arranged in order from the object side. It has a third lens group (G3), and at the time of focusing, the second lens group (G2) moves along the optical axis and satisfies the following conditional expression. -5.000 <(-G1R1) / f <500.0000.20 <f2 / (-f3) <1.20 However, f2: focal length of the second lens group (G2) f3: third lens group (G3) ) Focal length f: Focal length of the optical system (LS) G1R1: Radius of curvature of the lens surface on the object side in the lens component arranged on the most object side of the first lens group (G1).

Description

The present invention relates to optical systems, optical instruments, and methods for manufacturing optical systems.

Conventionally, an inner focus type single focus optical system (see, for example, Patent Document 1) has been proposed in which a group of positive lenses arranged on the image side of an aperture is extended toward an object side to focus. With such an optical system, it has been difficult to satisfactorily correct various aberrations when the diameter is increased.

Japanese Unexamined Patent Publication No. 2012-234169

The optical system according to the first aspect includes a first lens group having a positive refractive power, a second lens group having a positive refractive power, and a third lens having a negative refractive power arranged in order from the object side. It has a group, and at the time of focusing, the second lens group moves along the optical axis and satisfies the following conditional expression.
-5.000 <(-G1R1) / f <500.000
0.20 <f2 / (-f3) <1.20
However, f2: the focal length of the second lens group f3: the focal length of the third lens group f: the focal length of the optical system G1R1: the object side of the lens component arranged on the most object side of the first lens group. Radical length of the lens surface of

The optical device according to the second aspect includes the above optical system.

The method for manufacturing an optical system according to a third aspect has a first lens group having a positive refractive power, a second lens group having a positive refractive power, and a negative refractive power arranged in order from the object side. A method for manufacturing an optical system having a third lens group, in which the second lens group moves along an optical axis during focusing and is contained in a lens barrel so as to satisfy the following conditional expression. Place each lens.
-5.000 <(-G1R1) / f <500.000
0.20 <f2 / (-f3) <1.20
However, f2: the focal length of the second lens group f3: the focal length of the third lens group f: the focal length of the optical system G1R1: the object side of the lens component arranged on the most object side of the first lens group. Radical length of the lens surface of

It is a lens block diagram in the infinity focusing state of the optical system which concerns on 1st Example. FIG. 2A is a diagram of various aberrations of the optical system according to the first embodiment during infinity focusing, and FIG. 2B is a diagram of various aberrations of the optical system according to the first embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 2nd Example. FIG. 4A is a diagram of various aberrations of the optical system according to the second embodiment during infinity focusing, and FIG. 4B is a diagram of various aberrations of the optical system according to the second embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 3rd Example. FIG. 6A is a diagram of various aberrations of the optical system according to the third embodiment during infinity focusing, and FIG. 6B is a diagram of various aberrations of the optical system according to the third embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 4th Example. FIG. 8A is a diagram of various aberrations of the optical system according to the fourth embodiment during infinity focusing, and FIG. 8B is a diagram of various aberrations of the optical system according to the fourth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 5th Example. FIG. 10A is a diagram of various aberrations of the optical system according to the fifth embodiment during infinity focusing, and FIG. 10B is a diagram of various aberrations of the optical system according to the fifth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 6th Example. FIG. 12A is a diagram of various aberrations of the optical system according to the sixth embodiment during infinity focusing, and FIG. 12B is a diagram of various aberrations of the optical system according to the sixth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 7th Example. FIG. 14 (A) is a diagram of various aberrations of the optical system according to the seventh embodiment during infinity focusing, and FIG. 14 (B) is a diagram of various aberrations of the optical system according to the seventh embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 8th Example. FIG. 16A is a diagram of various aberrations of the optical system according to the eighth embodiment during infinity focusing, and FIG. 16B is a diagram of various aberrations of the optical system according to the eighth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 9th Example. FIG. 18A is a diagram of various aberrations of the optical system according to the ninth embodiment during infinity focusing, and FIG. 18B is a diagram of various aberrations of the optical system according to the ninth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 10th Example. FIG. 20A is a diagram of various aberrations of the optical system according to the tenth embodiment during infinity focusing, and FIG. 20B is a diagram of various aberrations of the optical system according to the tenth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on eleventh embodiment. FIG. 22 (A) is a diagram of various aberrations of the optical system according to the eleventh embodiment during infinity focusing, and FIG. 22 (B) is a diagram of various aberrations of the optical system according to the eleventh embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on a twelfth embodiment. FIG. 24 (A) is a diagram of various aberrations of the optical system according to the twelfth embodiment during infinity focusing, and FIG. 24 (B) is a diagram of various aberrations of the optical system according to the twelfth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 13th Example. FIG. 26A is a diagram of various aberrations of the optical system according to the thirteenth embodiment during infinity focusing, and FIG. 26B is a diagram of various aberrations of the optical system according to the thirteenth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 14th Example. FIG. 28 (A) is a diagram of various aberrations of the optical system according to the 14th embodiment during infinity focusing, and FIG. 28 (B) is a diagram of various aberrations of the optical system according to the 14th embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 15th Example. FIG. 30A is a diagram of various aberrations of the optical system according to the fifteenth embodiment during infinity focusing, and FIG. 30B is a diagram of various aberrations of the optical system according to the fifteenth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on the 16th Example. FIG. 32 (A) is a diagram of various aberrations of the optical system according to the 16th embodiment during infinity focusing, and FIG. 32 (B) is a diagram of various aberrations of the optical system according to the 16th embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 17th Example. FIG. 34 (A) is a diagram of various aberrations of the optical system according to the 17th embodiment during infinity focusing, and FIG. 34 (B) is a diagram of various aberrations of the optical system according to the 17th embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 18th Example. FIG. 36 (A) is a diagram of various aberrations of the optical system according to the eighteenth embodiment during infinity focusing, and FIG. 36 (B) is a diagram of various aberrations of the optical system according to the eighteenth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 19th Example. FIG. 38 (A) is a diagram of various aberrations of the optical system according to the 19th embodiment during infinity focusing, and FIG. 38 (B) is a diagram of various aberrations of the optical system according to the 19th embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 20th Example. FIG. 40 (A) is a diagram of various aberrations of the optical system according to the twentieth embodiment during infinity focusing, and FIG. 40 (B) is a diagram of various aberrations of the optical system according to the twentieth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 21st Example. FIG. 42 (A) is a diagram of various aberrations of the optical system according to the 21st embodiment during infinity focusing, and FIG. 42 (B) is a diagram of various aberrations of the optical system according to the 21st embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 22nd Example. FIG. 44 (A) is a diagram of various aberrations of the optical system according to the 22nd embodiment during infinity focusing, and FIG. 44 (B) is a diagram of various aberrations of the optical system according to the 22nd embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 23rd Example. FIG. 46 (A) is a diagram of various aberrations of the optical system according to the 23rd embodiment during infinity focusing, and FIG. 46 (B) is a diagram of various aberrations of the optical system according to the 23rd embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 24th Example. FIG. 48 (A) is a diagram of various aberrations of the optical system according to the 24th embodiment during infinity focusing, and FIG. 48 (B) is a diagram of various aberrations of the optical system according to the 24th embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on the 25th Example. FIG. 50 (A) is a diagram of various aberrations of the optical system according to the 25th embodiment during infinity focusing, and FIG. 50 (B) is a diagram of various aberrations of the optical system according to the 25th embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on the 26th Example. FIG. 52 (A) is a diagram of various aberrations of the optical system according to the 26th embodiment during infinity focusing, and FIG. 52 (B) is a diagram of various aberrations of the optical system according to the 26th embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 27th Embodiment. FIG. 54 (A) is a diagram of various aberrations of the optical system according to the 27th embodiment during infinity focusing, and FIG. 54 (B) is a diagram of various aberrations of the optical system according to the 27th embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 28th Example. FIG. 56 (A) is a diagram of various aberrations of the optical system according to the 28th embodiment during infinity focusing, and FIG. 56 (B) is a diagram of various aberrations of the optical system according to the 28th embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 29th Embodiment. FIG. 58 (A) is a diagram of various aberrations of the optical system according to the 29th embodiment during infinity focusing, and FIG. 58 (B) is a diagram of various aberrations of the optical system according to the 29th embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 30th Example. FIG. 60 (A) is a diagram of various aberrations of the optical system according to the thirtieth embodiment during infinity focusing, and FIG. 60 (B) is a diagram of various aberrations of the optical system according to the thirtieth embodiment during short-distance focusing. It is a figure. It is a lens block diagram in the infinity focusing state of the optical system which concerns on 31st Example. FIG. 62 (A) is a diagram of various aberrations of the optical system according to the 31st embodiment at infinity focusing, and FIG. 62 (B) shows various aberrations of the optical system according to the 31st embodiment at the time of short-distance focusing. It is a figure. It is a figure which shows the structure of the camera provided with the optical system which concerns on this embodiment. It is a flowchart which shows the manufacturing method of the optical system which concerns on this embodiment.

Hereinafter, the optical system and the optical device according to the present embodiment will be described with reference to the drawings. First, a camera (optical device) provided with an optical system according to the present embodiment will be described with reference to FIG. 63. As shown in FIG. 63, the camera 1 is a digital camera provided with an optical system according to the present embodiment as a photographing lens 2. In the camera 1, the light from an object (subject) (not shown) is collected by the photographing lens 2 and reaches the image sensor 3. As a result, the light from the subject is captured by the image sensor 3 and recorded as a subject image in a memory (not shown). In this way, the photographer can shoot the subject with the camera 1. This camera may be a mirrorless camera or a single-lens reflex type camera having a quick return mirror.

As shown in FIG. 1, the optical system LS (1) as an example of the optical system (photographing lens) LS according to the present embodiment includes a first lens group G1 having a positive refractive power arranged in order from the object side. It is composed of a second lens group G2 having a positive refractive power and a third lens group G3 having a negative refractive power. At the time of focusing, the second lens group G2 moves along the optical axis. This makes it possible to obtain good optical performance while suppressing changes in image magnification from the infinity focusing state to the short distance focusing state.

The optical system LS according to the present embodiment is not limited to the optical system LS (1) shown in FIG. 1, and may be the optical system LS (2) shown in FIG. Similarly, the optical system LS according to the present embodiment may be the optical systems LS (3) to LS (31) shown in FIGS. 5 and 5 and thereafter.

Under the above configuration, the optical system LS according to the present embodiment satisfies the following conditional expression.

-5.000 <(-G1R1) / f <500.000 ... (1)
0.20 <f2 / (-f3) <1.20 ... (2)
However, f2: the focal length of the second lens group G2 f3: the focal length of the third lens group G3 f: the focal length of the optical system LS G1R1: the object side of the lens component arranged on the most object side of the first lens group G1. Radical length of the lens surface of

The conditional expression (1) defines an appropriate range of the ratio between the radius of curvature of the lens surface on the most object side of the first lens group G1 and the focal length of the entire optical system LS. By satisfying the conditional expression (1), good optical performance can be ensured in the infinity in-focus state. In the present embodiment, the lens component indicates a single lens or a junction lens.

When the corresponding value of the conditional expression (1) exceeds the upper limit value, the radius of curvature of the lens surface on the most object side of the first lens group G1 becomes smaller, so that the amount of various aberrations generated increases and the coma at the time of focusing increases. The fluctuation of aberration becomes large. By setting the upper limit value of the conditional expression (1) to 400.000, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of this embodiment, the upper limit of the conditional expression (1) is set to 300.000, 200.000, 100.000, 85.000, 75.000, 60.000, 45.000. It is preferably 30.000, more preferably 20.000.

When the corresponding value of the conditional expression (1) is less than the lower limit value, the radius of curvature of the lens surface on the most object side of the first lens group G1 becomes large, so that it becomes difficult to correct coma. By setting the lower limit value of the conditional expression (1) to -4.00, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the lower limit of the conditional expression (1) is set to -3000, -2000, -1.00, 0.010, 0.100, 0.200, It is preferably 0.250, 0.300, 0.350, 0.400, 0.450, 0.500, 0.550, 0.600, 0.650, and further 0.700.

The conditional expression (2) defines an appropriate range of the ratio between the focal length of the second lens group G2 and the focal length of the third lens group G3. By satisfying the conditional expression (2), good optical performance can be ensured in a short-distance focusing state.

When the corresponding value of the conditional expression (2) exceeds the upper limit value, the focal length of the second lens group G2 becomes long, so that the amount of movement of the second lens group G2 during focusing increases, and the amount of movement during focusing increases. Fluctuations in spherical aberration and curvature of field increase. By setting the upper limit value of the conditional expression (2) to 1.00, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of this embodiment, the upper limit of the conditional expression (2) is set to 0.95, 0.90, 0.88, 0.85, 0.80, 0.77, 0.75. , 0.72, 0.70, and more preferably 0.68.

When the corresponding value of the conditional expression (2) is less than the lower limit value, the focal length of the second lens group G2 becomes short, so that the amount of various aberrations generated increases and the fluctuation of coma during focusing becomes large. Further, since the focal length of the third lens group G3 becomes longer on the minus side, it becomes difficult to correct various aberrations, and the curvature of field at the time of focusing becomes large. By setting the lower limit value of the conditional expression (2) to 0.23, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the lower limit of the conditional expression (2) is set to 0.29, 0.35, 0.37, 0.39, 0.40, 0.41, and further 0. It is preferably 42.

It is desirable that the optical system LS of the present embodiment satisfies the following conditional expression (3).
-5.000 <(-G1R1) / f1 <50.000 ... (3)
However, f1: the focal length of the first lens group G1

Conditional expression (3) defines an appropriate range of the ratio between the radius of curvature of the lens surface on the most object side of the first lens group G1 and the focal length of the first lens group G1. By satisfying the conditional expression (3), good optical performance can be ensured in the infinity in-focus state.

When the corresponding value of the conditional expression (3) exceeds the upper limit value, the radius of curvature of the lens surface on the most object side of the first lens group G1 becomes smaller, so that the amount of various aberrations generated increases and the coma at the time of focusing increases. The fluctuation of aberration becomes large. By setting the upper limit value of the conditional expression (3) to 40.000, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the upper limit of the conditional expression (3) is preferably 30.000, 20.000, 10.000, and further 5.000.

When the corresponding value of the conditional expression (3) is less than the lower limit value, the radius of curvature of the lens surface on the most object side of the first lens group G1 becomes large, so that it becomes difficult to correct coma. By setting the lower limit value of the conditional expression (3) to -4.00, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the lower limit of the conditional expression (3) is set to -3000, -2000, -1.00, 0.010, 0.050, 0.100, It is preferably 0.150, 0.200, 0.250, 0.300, 0.350, 0.400, 0.450, and more preferably 0.500.

The optical system LS of the present embodiment may satisfy the following conditional expression (3-1).
0.010 <(-G1R1) /f1 <1.10 ... (3-1)
However, f1: the focal length of the first lens group G1

The conditional expression (3-1) is the same expression as the conditional expression (3), and the same effect as the conditional expression (3) can be obtained. Within this range, various aberrations such as coma are satisfactorily corrected, which is preferable. In particular, by setting the lower limit value of the conditional expression (3-1) to 0.050, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of this embodiment, the lower limit of the conditional expression (3-1) is set to 0.100, 0.150, 0.200, 0.250, 0.300, 0.350, 0. It is preferably .400, 0.450, and more preferably 0.500.

The optical system LS of the present embodiment may satisfy the following conditional expression (3-2).
1.000 <(-G1R1) /f1 <50.000 ... (3-2)
However, f1: the focal length of the first lens group G1

The conditional expression (3-2) is the same expression as the conditional expression (3), and the same effect as the conditional expression (3) can be obtained. Within this range, various aberrations such as coma are satisfactorily corrected, which is preferable. In particular, by setting the upper limit value of the conditional expression (3-2) to 40.000, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the upper limit of the conditional expression (3-2) is preferably 30.000, 20.000, 10.000, and further 5.000.

In the optical system LS of the present embodiment, it is desirable that the first lens group G1 has an aperture. Thereby, various aberrations such as coma aberration and astigmatism in the short-distance focusing state can be satisfactorily corrected.

In the optical system LS of the present embodiment, it is desirable that the first lens group G1 is fixed. As a result, the entire optical system LS can be miniaturized.

It is desirable that the optical system LS of the present embodiment satisfies the following conditional expression (4).
0.010 <f / f1 <5.000 ... (4)
However, f1: the focal length of the first lens group G1

The conditional expression (4) defines an appropriate range of the ratio between the focal length of the entire optical system LS and the focal length of the first lens group G1. By satisfying the conditional expression (4), good optical performance can be ensured in the infinity in-focus state.

When the corresponding value of the conditional expression (4) exceeds the upper limit value, the focal length of the first lens group G1 becomes short, so that the amount of various aberrations generated increases and the fluctuation of coma during focusing becomes large. By setting the upper limit value of the conditional expression (4) to 4.500, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of this embodiment, the upper limit of the conditional expression (4) is set to 4.000, 3.500, 3.000, 2.500, 2.000, 1.500, 1.200. , Further preferably 1.000.

If the corresponding value of the conditional expression (4) is less than the lower limit value, the focal length of the first lens group G1 becomes long, and it becomes difficult to correct the coma aberration. By setting the lower limit value of the conditional expression (4) to 0.050, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the lower limit of the conditional expression (4) is set to 0.100, 0.150, 0.200, 0.250, 0.300, 0.350, 0.400. , 0.450, 0.500, and more preferably 0.550.

It is desirable that the optical system LS of the present embodiment satisfies the following conditional expression (5).
0.010 <f / f2 <5.000 ... (5)

The conditional expression (5) defines an appropriate range of the ratio between the focal length of the entire optical system LS and the focal length of the second lens group G2. By satisfying the conditional expression (5), good optical performance can be ensured in a short-distance focusing state.

When the corresponding value of the conditional expression (5) exceeds the upper limit value, the focal length of the second lens group G2 becomes short, so that the amount of various aberrations generated increases and the fluctuation of coma during focusing becomes large. By setting the upper limit value of the conditional expression (5) to 4.500, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of this embodiment, the upper limit of the conditional expression (5) is set to 4.000, 3.500, 3.000, 2.500, 2.000, 1.800, 1.500. , Further preferably 1.300.

When the corresponding value of the conditional expression (5) is less than the lower limit value, the focal length of the second lens group G2 becomes long, so that the amount of movement of the second lens group G2 during focusing increases, and the amount of movement during focusing increases. Fluctuations in spherical aberration and curvature of field increase. By setting the lower limit value of the conditional expression (5) to 0.050, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the lower limit of the conditional expression (5) is set to 0.100, 0.150, 0.200, 0.250, 0.300, 0.350, 0.400. , 0.450, 0.500, 0.550, 0.600, and more preferably 0.650.

It is desirable that the optical system LS of the present embodiment satisfies the following conditional expression (6).
0.010 <f1 / f2 <5.000 ... (6)
However, f1: the focal length of the first lens group G1

The conditional expression (6) defines an appropriate range of the ratio between the focal length of the first lens group G1 and the focal length of the second lens group G2. By satisfying the conditional expression (6), good optical performance can be ensured in the infinity focusing state and the short distance focusing state.

When the corresponding value of the conditional expression (6) exceeds the upper limit value, the focal length of the second lens group G2 becomes short, so that the amount of various aberrations generated increases and the fluctuation of coma during focusing becomes large. By setting the upper limit value of the conditional expression (6) to 4.000, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the upper limit of the conditional expression (6) is preferably 3.500, 3.000, 2.500, 2.000, and further 1.800.

When the corresponding value of the conditional expression (6) is less than the lower limit value, the focal length of the second lens group G2 becomes long, so that the amount of movement of the second lens group G2 during focusing increases, and the amount of movement during focusing increases. Fluctuations in spherical aberration and curvature of field increase. By setting the lower limit value of the conditional expression (6) to 0.100, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the lower limit of the conditional expression (6) is set to 0.200, 0.250, 0.300, 0.350, 0.400, 0.450, 0.500. , 0.600, 0.700, 0.800, and more preferably 0.900.

It is desirable that the optical system LS of the present embodiment satisfies the following conditional expression (7).
0.100 <BFa / f <0.500 ... (7)
However, Bfa: the air conversion distance on the optical axis from the lens surface on the image side to the image surface in the lens arranged on the most image side of the optical system LS.

The conditional expression (7) defines an appropriate range of the ratio between the focal length of the entire optical system LS and the back focus. By satisfying the conditional expression (7), astigmatism can be satisfactorily corrected.

If the corresponding value of the conditional expression (7) exceeds the upper limit value, it becomes difficult to correct the astigmatism. By setting the upper limit value of the conditional expression (7) to 0.450, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the upper limit of the conditional expression (7) is preferably 0.420, 0.400, 0.380, 0.350, and further 0.320.

Even if the corresponding value of the conditional expression (7) is less than the lower limit value, it becomes difficult to correct the astigmatism. By setting the lower limit value of the conditional expression (7) to 0.110, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the lower limit of the conditional expression (7) is set to 0.120, 0.130, 0.140, 0.150, 0.160, and further 0.170. Is preferable.

It is desirable that the optical system LS of the present embodiment satisfies the following conditional expression (8).
0.10 <fF / fR <3.00 ... (8)
However, fF: the combined focal length of the lens arranged on the object side of the aperture in the optical system LS fR: the combined focal length of the lens arranged on the image side of the aperture in the optical system LS.

Conditional expression (8) defines an appropriate range of the ratio between the combined focal length of the lens arranged on the object side of the aperture and the combined focal length of the lens arranged on the image side of the aperture. Each composite focal length is the composite focal length in the infinity in-focus state. By satisfying the conditional expression (8), astigmatism and distortion can be satisfactorily corrected.

If the corresponding value of the conditional expression (8) exceeds the upper limit value, it becomes difficult to correct astigmatism and distortion. By setting the upper limit value of the conditional expression (8) to 2.50, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the upper limit of the conditional expression (8) is preferably 2.00, 1.80, 1.50, 1.20, and further 1.10.

Even if the corresponding value of the conditional expression (8) is less than the lower limit value, it becomes difficult to correct astigmatism and distortion. By setting the lower limit value of the conditional expression (8) to 0.20, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, it is preferable that the lower limit of the conditional expression (8) is 0.25, 0.25, 0.30, 0.34, and further 0.35.

It is desirable that the optical system LS of the present embodiment satisfies the following conditional expression (9).
-10.0 <(G1R2 + G1R1) / (G1R2-G1R1) <10.0 ... (9)
However, G1R2: radius of curvature of the lens surface on the image side in the lens component arranged on the most object side of the first lens group G1.

The conditional expression (9) defines the shape factor of the lens component arranged on the most object side of the first lens group G1. By satisfying the conditional expression (9), good optical performance can be ensured in the infinity in-focus state.

When the corresponding value of the conditional expression (9) exceeds the upper limit value, the curvature of the lens surface on the object side in the lens component arranged on the most object side of the first lens group G1 becomes tight, so that the amount of various aberrations generated increases. However, the fluctuation of coma aberration during focusing becomes large. By setting the upper limit value of the conditional expression (9) to 8.0, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the upper limit of the conditional expression (9) is preferably 7.0, 6.0, 5.0, and further 4.0.

When the corresponding value of the conditional expression (9) is less than the lower limit value, the curvature of the lens surface on the object side in the lens component arranged on the most object side of the first lens group G1 becomes loose, and it becomes difficult to correct the coma aberration. Become. By setting the lower limit value of the conditional expression (9) to −8.0, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of this embodiment, the lower limit of the conditional expression (9) is set to -7.0, -6.0, -5.0, -4.0, -3.0, and further-. It is preferably 2.0.

It is desirable that the optical system LS of the present embodiment satisfies the following conditional expression (10).
0.30 << {1- (β2) ² } × (β3) ² <2.00 ... (10)
However, β2: lateral magnification of the second lens group G2 in the infinity focusing state β3: lateral magnification of the third lens group G3

The conditional expression (10) defines the amount of displacement of the focal position with respect to the movement of the second lens group G2. By satisfying the conditional expression (10), good optical performance can be ensured on-axis and off-axis in a short-distance focusing state.

If the corresponding value of the conditional expression (10) exceeds the upper limit value, it becomes difficult to correct coma and astigmatism in the short-distance focusing state. By setting the upper limit value of the conditional expression (10) to 1.80, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the upper limit of the conditional expression (10) is set to 1.60, 1.40, 1.20, 1.00, 0.95, 0.91, and further 0. It is preferably 89.

Even if the corresponding value of the conditional expression (10) is less than the lower limit value, it becomes difficult to correct coma and astigmatism in the short-distance focusing state. By setting the lower limit value of the conditional expression (10) to 0.35, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the lower limit of the conditional expression (10) is preferably 0.40, 0.45, 0.48, and further 0.50.

It is desirable that the optical system LS of the present embodiment satisfies the following conditional expression (11).
0.50 <FNO × (f1 / f) <5.50 ... (11)
However, FNO: F number of the optical system LS f1: Focal length of the first lens group G1

The conditional expression (11) defines a value corresponding to the F number of the first lens group G1. By satisfying the conditional expression (11), various aberrations such as coma can be satisfactorily corrected.

If the corresponding value of the conditional expression (11) exceeds the upper limit value, it becomes difficult to correct coma and astigmatism. By setting the upper limit value of the conditional expression (11) to 5.00, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the upper limit of the conditional expression (11) is preferably 4.50, 4.00, 3.50, 3.20, and further 3.00.

Even if the corresponding value of the conditional expression (11) is less than the lower limit value, it becomes difficult to correct the spherical aberration and the coma aberration. By setting the lower limit value of the conditional expression (11) to 0.80, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, it is preferable that the lower limit of the conditional expression (11) is 1.00, 1.40, 1.60, 1.80, and further 1.95.

It is desirable that the optical system LS of the present embodiment satisfies the following conditional expression (12).
15.0 ° <2ω <85.0 ° ・ ・ ・ (12)
However, 2ω: angle of view of the optical system LS

The conditional expression (12) defines the angle of view of the optical system LS. By satisfying the conditional expression (12), various aberrations can be satisfactorily corrected while having a wide angle of view. By setting the upper limit value of the conditional expression (12) to 80.0 °, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the upper limit of the conditional expression (12) is preferably 75.0 °, 70.0 °, 68.0 °, and further 65.0 °. By setting the lower limit value of the conditional expression (12) to 17.0 °, the effect of the present embodiment can be made more reliable. In order to further ensure the effect of the present embodiment, the lower limit of the conditional expression (12) is preferably set to 18.0 °, 20.0 °, 22.0 °, and further 25.0 °.

In the optical system LS of the present embodiment, the lens arranged on the object side of the first lens group G1 may be a negative lens. As a result, coma aberration can be satisfactorily corrected.

In the optical system LS of the present embodiment, the lens arranged on the object side of the second lens group G2 may be a negative lens. Thereby, the curvature of field can be satisfactorily corrected.

In the optical system LS of the present embodiment, the second lens group G2 may have at least one positive lens and at least one negative lens. Thereby, various aberrations such as chromatic aberration can be satisfactorily corrected.

In the optical system LS of the present embodiment, the third lens group G3 may have at least one positive lens and at least one negative lens. Thereby, various aberrations such as chromatic aberration can be satisfactorily corrected.

Subsequently, the method for manufacturing the above-mentioned optical system LS will be outlined with reference to FIG. 64. First, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the third lens group G3 having a negative refractive power are arranged in order from the object side (). Step ST1). Then, at the time of focusing, the second lens group G2 is configured to move along the optical axis (step ST2). Further, each lens is arranged in the lens barrel so as to satisfy at least the above conditional expressions (1) and (2) (step ST3). According to such a manufacturing method, it is possible to manufacture an optical system capable of obtaining good optical performance while suppressing a change in image magnification from an infinity focusing state to a short distance focusing state.

Hereinafter, the optical system LS according to the embodiment of the present embodiment will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing the configuration and refractive power distribution of the optical system LS {LS (1)} according to the first embodiment. Similarly, FIGS. 3, 5, 7, 9, 9, 11, 13, 15, 17, 17, 19, and 21 show the optical system LS {LS (2) according to the second to eleventh embodiments. ) To LS (11)} and a cross-sectional view showing the refractive power distribution. 23, 25, 27, 29, 31, 33, 35, 37, 39, 41 are optical systems LS {LS (12) to LS according to the twelfth to twenty-first embodiments. It is sectional drawing which shows the structure of (21)} and the refractive power distribution. 43, 45, 47, 49, 51, 53, 55, 57, 59, 61 are optical systems LS {LS (22) to LS according to the 22nd to 31st embodiments. It is sectional drawing which shows the structure of (31)} and the refractive power distribution. In each cross-sectional view, the direction of movement when the focusing lens group focuses on a short-range object from infinity is indicated by an arrow together with the word "focus".

In these figures, each lens group is represented by a combination of reference numerals G and numbers, and each lens is represented by a combination of reference numerals L and numbers. In this case, in order to prevent the types and numbers of the symbols and numbers from becoming large and complicated, the lens group and the like are represented by independently using combinations of the symbols and numbers for each embodiment. Therefore, even if the same combination of reference numerals and numbers is used between the examples, it does not mean that they have the same configuration.

Tables 1 to 31 are shown below, and Tables 1 to 31 are tables showing each specification data in the first to 31st examples. In each embodiment, the d-line (wavelength λ = 587.6 nm) is selected as the calculation target of the aberration characteristics.

In the [Overall specifications] table, f is the focal length of the entire lens system, FNO is the F number, ω is the half angle of view (unit is ° (degrees)), and Y is the image height. TL indicates the distance from the frontmost surface of the lens to the final surface of the lens on the optical axis at infinity, plus BF, and BF is the image from the final surface of the lens on the optical axis at infinity. The distance to the surface I (back focus) is shown, and BFa shows the air-equivalent length of the back focus.

In the [Lens Specifications] table, the surface numbers indicate the order of the optical surfaces from the object side along the direction in which the light beam travels, and R is the radius of curvature of each optical surface (the surface whose center of curvature is located on the image side). (Positive value), D is the distance on the optical axis from each optical surface to the next optical surface (or image surface), nd is the refractive index of the material of the optical member with respect to the d line, and νd is optical. The Abbe number based on the d-line of the material of the member is shown. The radius of curvature "∞" indicates a plane or an aperture, and (aperture S) indicates an aperture stop S. The description of the refractive index nd of air = 1.00000 is omitted. When the optical surface is aspherical, the surface number is marked with *, and the column of radius of curvature R indicates the paraxial radius of curvature.

In the table of [Aspherical surface data], the shape of the aspherical surface shown in [Lens specifications] is shown by the following equation (A). X (y) is the distance (zag amount) along the optical axis direction from the tangent plane at the aspherical apex to the position on the aspherical surface at the height y, and R is the radius of curvature of the reference sphere (near-axis radius of curvature). , Κ indicates the conical constant, and Ai indicates the i-th order aspherical coefficient. "E-n" indicates " ^{x10 -n".} For example, 1.234E-05 = 1.234 × 10 ^-5 . The second-order aspherical coefficient A2 is 0, and the description thereof is omitted.

The table of [variable spacing data] shows the surface spacing Di up to the next surface at the surface number i in which the surface spacing is "variable" in the table showing [lens specifications]. For example, in the first embodiment, the surface spacings D11, D17, and D23 at the surface numbers 11, 17, and 23 are shown. These values are shown for each of the infinity in-focus state and the short-distance (close-distance) in-focus state.

The [lens group data] table shows the starting surface (the surface closest to the object) and the focal length of each lens group.

The table of [Conditional expression corresponding values] shows the values corresponding to each conditional expression.

Hereinafter, in all the specification values, "mm" is generally used for the focal length f, the radius of curvature R, the plane spacing D, other lengths, etc., unless otherwise specified, but the optical system is expanded proportionally. Alternatively, it is not limited to this because the same optical performance can be obtained even if the proportional reduction is performed.

The description of the table so far is common to all the examples, and the duplicate description below is omitted.

(First Example)
The first embodiment will be described with reference to FIGS. 1 to 2 and Table 1. FIG. 1 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the first embodiment of the present embodiment. In the optical system LS (1) according to the first embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. .. The symbol (+) or (-) attached to each lens group symbol indicates the refractive power of each lens group, and this also applies to all the following examples.

The first lens group G1 includes a meniscus-shaped first negative lens L11 having a concave surface facing the object side, a meniscus-shaped first positive lens L12 having a concave surface facing the object side, and biconvex lenses arranged in order from the object side. It is composed of a second positive lens L13 having a shape, a third positive lens L14 having a biconvex shape, a second negative lens L15 having a meniscus shape with a convex surface facing the object side, and an aperture stop S. The second positive lens L13 has aspherical lens surfaces on both sides.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a meniscus-shaped lens L22 having a concave surface facing the object side, arranged in order from the object side. It is composed of a second positive lens L23. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a biconcave-shaped negative lens L32 arranged in order from the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I. As the interchangeable optical filter FL, for example, an NC filter (neutral color filter), a color filter, a polarizing filter, an ND filter (neutral density filter), an IR filter (infrared cut filter) and the like are used. The same applies to the interchangeable optical filter FL described in the second to 31st Examples described later.

Table 1 below lists the values of the specifications of the optical system according to the first embodiment.

(Table 1)
[Overall specifications]
f 51.59
FNO 1.85
ω 22.6
Y 21.70
TL 80.800
BF 13.599
BFa 13.054
[Lens specifications]
Surface number RD nd νd
1 -37.21999 1.800 1.60342 38.0
2-301.75553 2.422
3 -50.10561 3.350 1.49782 82.6
4 -32.57310 0.200
5 * 45.59156 5.050 1.82080 42.7
6 * -214.20431 0.200
7 24.72595 7.194 1.59319 67.9
8-5040.38050 0.100
9 1752.78680 1.000 1.60342 38.0
10 18.45027 5.608
11 ∞ D11 (variable) (aperture S)
12 -23.43011 1.000 1.67270 32.2
13 -582.82234 0.200
14 * 127.87476 4.350 1.82080 42.7
15 * -43.94757 1.950
16 -157.95993 5.600 1.60300 65.4
17 -28.85150 D17 (variable)
18 -374.08672 3.200 2.00100 29.1
19 -68.25108 4.109
20 -36.81307 1.500 1.69895 30.1
21 177.00000 11.000
22 ∞ 1.600 1.51680 63.9
23 ∞ D23 (variable)
[Aspherical data]
Side 5 κ = 1.0000
A4 = -1.10646E-06, A6 = -5.14585E-10, A8 = 0.00000E + 00, A10 = 0.00000E + 00
Side 6 κ = 1.0000
A4 = 3.82437E-07, A6 = -2.48354E-10, A8 = 0.00000E + 00, A10 = 0.0000E + 00
14th surface κ = 1.0000
A4 = 2.59966E-06, A6 = 2.78570E-09, A8 = 0.00000E + 00, A10 = 0.0000E + 00
Surface 15 κ = 1.0000
A4 = 9.97453E-06, A6 = 1.00933E-08, A8 = 0.00000E + 00, A10 = 0.0000E + 00
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.59 β = -0.1508
D0 ∞ 319.20
D11 15.367 5.165
D17 3.000 13.203
D23 0.999 0.999
[Lens group data]
Focal length
G1 1 68.17
G2 12 56.22
G3 18 -101.37
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.721
Conditional expression (2) f2 / (-f3) = 0.555
Conditional expressions (3), (3-1), (3-2)
(-G1R1) / f1 = 0.546
Conditional expression (4) f / f1 = 0.757
Conditional expression (5) f / f2 = 0.918
Conditional expression (6) f1 / f2 = 1.213
Conditional expression (7) BFa / f = 0.253
Conditional expression (8) fF / fR = 0.646
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 1.281
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.613
Conditional expression (11) FNO × (f1 / f) = 2.451
Conditional expression (12) 2ω = 45.2

FIG. 2A is an aberration diagram at infinity focusing of the optical system according to the first embodiment. In each aberration diagram of FIG. 2A, FNO indicates an F number and A indicates a half angle of view. The spherical aberration diagram shows the value of the F number corresponding to the maximum aperture, the astigmatism diagram and the distortion diagram show the maximum value of the half angle of view, and the transverse aberration diagram shows the value of each half angle of view. FIG. 2B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the first embodiment. In each aberration diagram of FIG. 2B, NA indicates the numerical aperture and H0 indicates the object height. The spherical aberration diagram shows the numerical aperture value corresponding to the maximum aperture, the astigmatism diagram and the distortion aberration diagram show the maximum value of the object height, and the transverse aberration diagram shows the value of each object height. Further, in the astigmatism diagrams of FIGS. 2 (A) and 2 (B), the solid line indicates the sagittal image plane and the broken line indicates the meridional image plane. In the aberration diagrams of each of the following examples, the same reference numerals as those of the present embodiment will be used, and duplicate description will be omitted.

From each aberration diagram, it can be seen that the optical system according to the first embodiment has various aberrations corrected well and has excellent imaging performance.

(Second Example)
The second embodiment will be described with reference to FIGS. 3 to 4 and Table 2. FIG. 3 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the second embodiment of the present embodiment. In the optical system LS (2) according to the second embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 is a junction lens composed of a meniscus-shaped first negative lens L11 having a concave surface facing the object side and a meniscus-shaped first positive lens L12 having a convex surface facing the object side, arranged in order from the object side. It is composed of a meniscus-shaped second positive lens L13 with a concave surface facing the object side, a biconvex third positive lens L14, a biconvex fourth positive lens L15, and a biconcave second negative lens L16. It is composed of a bonded lens and an aperture aperture S. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 includes a biconcave negative lens L21, a biconvex first positive lens L22, and a meniscus-shaped second positive lens L23 with a concave surface facing the object side, which are arranged in order from the object side. , Consists of. The lens surface of the first positive lens L22 on the image plane I side is an aspherical surface.

The third lens group G3 includes a meniscus-shaped positive lens L31 with a concave surface facing the object side, a meniscus-shaped first negative lens L32 with a concave surface facing the object side, and a concave surface on the object side, which are arranged in order from the object side. It is composed of a second negative lens L33 having a flat concave shape and facing the lens. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 2 below lists the values of the specifications of the optical system according to the second embodiment. The thirteenth surface is a virtual surface.

(Table 2)
[Overall specifications]
f 51.60
FNO 1.85
ω 22.8
Y 21.70
TL 88.456
BF 13.100
BFa 12.555
[Lens specifications]
Surface number RD nd νd
1 -39.70605 1.800 1.73800 32.3
2 68.44172 3.469 1.92286 20.9
3 740.55070 0.985
4-250.61896 4.504 1.59319 67.9
5 -42.16654 0.200
6 * 41.73745 0.103 1.56093 36.6
7 40.99975 5.408 1.83481 42.7
8 -316.20679 0.200
9 36.83151 7.628 1.49782 82.6
10 -47.01014 1.500 1.62004 36.4
11 25.38130 4.386
12 ∞ D12 (variable) (aperture S)
13 ∞ 3.000
14 -22.68035 1.100 1.64769 33.7
15 219.09880 0.200
16 85.95366 4.848 1.83481 42.7
17 -48.70070 0.100 1.56093 36.6
18 * -38.65718 2.196
19 -133.55548 6.300 1.60300 65.4
20 -26.81373 D20 (variable)
21 -112.24414 2.782 1.90265 35.7
22 -53.62057 5.134
23 -41.69274 2.000 1.53172 48.8
24-133.37205 2.166
25 -49.50596 2.000 1.60342 38.0
26 ∞ 10.500
27 ∞ 1.600 1.51680 64.1
28 ∞ D28 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -8.44128E-07, A6 = 9.38473E-10, A8 = -2.90073E-12, A10 = 6.84753E-15
Surface 18 κ = 1.0000
A4 = 1.66834E-05, A6 = 1.07396E-08, A = 8 3.36895E-11, A10 = -1.25245E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.60 β = -0.1562
D0 ∞ 311.54
D12 10.848 2.392
D20 2.500 10.956
D28 1.000 1.000
[Lens group data]
Focal length
G1 1 78.05
G2 13 49.80
G3 21 -88.77
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.769
Conditional expression (2) f2 / (-f3) = 0.561
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.509
Conditional expression (4) f / f1 = 0.661
Conditional expression (5) f / f2 = 1.036
Conditional expression (6) f1 / f2 = 1.567
Conditional expression (7) BFa / f = 0.243
Conditional expression (8) fF / fR = 0.877
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.898
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.827
Conditional expression (11) FNO × (f1 / f) = 2.805
Conditional expression (12) 2ω = 45.6

FIG. 4A is an aberration diagram at infinity focusing of the optical system according to the second embodiment. FIG. 4B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the second embodiment. From each aberration diagram, it can be seen that the optical system according to the second embodiment has various aberrations corrected well and has excellent imaging performance.

(Third Example)
The third embodiment will be described with reference to FIGS. 5 to 6 and Table 3. FIG. 5 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the third embodiment of the present embodiment. In the optical system LS (3) according to the third embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 is a junction lens composed of a biconcave first negative lens L11 and a biconvex first positive lens L12 arranged in order from the object side, and a meniscus-shaped first lens having a concave surface facing the object side. It is composed of a biconvex third positive lens L14, a biconvex fourth positive lens L15, a biconcave second negative lens L16, and an aperture aperture S. Lens. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a meniscus-shaped lens L22 having a concave surface facing the object side, arranged in order from the object side. It is composed of a second positive lens L23. The lens surface of the first positive lens L22 on the image plane I side is an aspherical surface.

The third lens group G3 has a meniscus-shaped positive lens L31 having a concave surface facing the object side, a meniscus-shaped first negative lens L32 having a concave surface facing the object side, and a biconcave shape, which are arranged in order from the object side. It is composed of a second negative lens L33. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 3 below lists the values of the specifications of the optical system according to the third embodiment. The sixth and 14th surfaces are virtual surfaces.

(Table 3)
[Overall specifications]
f 51.60
FNO 1.86
ω 23.0
Y 21.70
TL 95.000
BF 13.826
BFa 13.291
[Lens specifications]
Surface number RD nd νd
1 -43.62202 1.800 1.95375 32.3
2 62.41759 5.000 1.84666 23.8
3 -281.93425 0.654
4-167.37782 5.500 1.59319 67.9
5 -40.10469 0.476
6 ∞ 0.000
7 * 39.95627 0.100 1.56093 36.6
8 41.35117 6.000 1.83481 42.7
9 -308.32218 0.200
10 32.49687 8.500 1.49782 82.6
11 -50.34522 1.500 1.58144 41.0
12 20.84633 5.400
13 ∞ D13 (variable) (aperture S)
14 ∞ 3.100
15 -19.87542 1.100 1.67270 32.2
16 -102.49215 0.200
17 349.06334 4.800 1.75500 52.3
18 -33.68733 0.100 1.56093 36.6
19 * -30.20400 1.700
20 -294.17915 6.900 1.49782 82.6
21 -26.73936 D21 (variable)
22 -208.87897 3.500 2.00069 25.5
23 -59.64897 4.172
24-45.02223 2.000 1.62004 36.4
25 -133.33333 2.419
26 -45.00000 2.000 1.62004 36.4
27 224.57692 11.236
28 ∞ 1.600 1.51680 64.1
29 ∞ D29 (variable)
[Aspherical data]
Side 7 κ = 1.0000
A4 = -1.17140E-06, A6 = 4.04242E-10, A8 = 0.00000E + 00, A10 = 0.00000E + 00
Surface 19 κ = 1.0000
A4 = 1.13379E-05, A6 = 1.62636E-08, A8 = 0.00000E + 00, A10 = 0.00000E + 00
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.60 β = -0.1591
D0 ∞ 305.00
D13 11.043 2.821
D21 3.000 11.223
D29 1.000 1.000
[Lens group data]
Focal length
G1 1 82.69
G2 14 49.27
G3 22 -80.88
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.845
Conditional expression (2) f2 / (-f3) = 0.609
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.528
Conditional expression (4) f / f1 = 0.624
Conditional expression (5) f / f2 = 1.047
Conditional expression (6) f1 / f2 = 1.678
Conditional expression (7) BFa / f = 0.258
Conditional expression (8) fF / fR = 0.923
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 1.366
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.881
Conditional expression (11) FNO × (f1 / f) = 2.983
Conditional expression (12) 2ω = 46.0

FIG. 6A is an aberration diagram at infinity focusing of the optical system according to the third embodiment. FIG. 6B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the third embodiment. From each aberration diagram, it can be seen that the optical system according to the third embodiment has various aberrations corrected well and has excellent imaging performance.

(Fourth Example)
The fourth embodiment will be described with reference to FIGS. 7 to 8 and Table 4. FIG. 7 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the fourth embodiment of the present embodiment. In the optical system LS (4) according to the fourth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a junction lens consisting of a biconcave first negative lens L11 arranged in order from the object side and a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and a concave surface on the object side. It consists of a meniscus-shaped second positive lens L13, a meniscus-shaped third positive lens L14 with a convex surface facing the object side, a biconvex fourth positive lens L15, and a biconcave second negative lens L16. It is composed of a bonded lens and an aperture aperture S. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 includes a biconcave negative lens L21, a biconvex first positive lens L22, and a meniscus-shaped second positive lens L23 with a concave surface facing the object side, which are arranged in order from the object side. , Consists of. The lens surface of the first positive lens L22 on the image plane I side is an aspherical surface.

The third lens group G3 includes a meniscus-shaped positive lens L31 with a concave surface facing the object side, a meniscus-shaped first negative lens L32 with a concave surface facing the object side, and a concave surface on the object side, which are arranged in order from the object side. It is composed of a second negative lens L33 having a meniscus shape and facing the lens. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 4 below lists the values of the specifications of the optical system according to the fourth embodiment. The thirteenth surface is a virtual surface.

(Table 4)
[Overall specifications]
f 51.60
FNO 1.85
ω 23.0
Y 21.70
TL 93.423
BF 13.099
BFa 12.554
[Lens specifications]
Surface number RD nd νd
1 -49.34582 1.800 1.64769 33.7
2 46.34338 4.852 1.94595 18.0
3 88.17135 2.830
4-385.68443 6.805 1.75500 52.3
5 -55.81519 0.100
6 * 32.37146 0.300 1.56093 36.6
7 34.78660 6.291 1.75500 52.3
8 3421.80810 0.200
9 34.21341 7.021 1.59319 67.9
10 -76.80721 1.500 1.64769 33.7
11 20.90542 5.045
12 ∞ D12 (variable) (aperture S)
13 ∞ 2.700
14 -23.99823 1.100 1.64769 33.7
15 814.45031 0.200
16 93.44777 5.100 1.80400 46.6
17 -40.16052 0.152 1.56093 36.6
18 * -34.60672 3.204
19 -128.30142 6.400 1.49782 82.6
20 -26.31276 D20 (variable)
21 -78.26552 2.798 1.94595 18.0
22 -44.00653 2.232
23 -46.73961 2.000 1.64769 33.7
24-150.55235 2.958
25 -40.00000 1.900 1.64769 33.7
26 -179.87126 10.500
27 ∞ 1.600 1.51680 64.1
28 ∞ D28 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -1.82369E-06, A6 = -1.73726E-09, A8 = 2.00735E-12, A10 = -4.32700E-15
Surface 18 κ = 1.0000
A4 = 1.61711E-05, A6 = 1.10899E-08, A8 = 3.81964E-11, A10 = -1.19949E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.60 β = -0.1563
D0 ∞ 306.58
D12 10.336 2.398
D20 2.500 10.438
D28 0.999 0.999
[Lens group data]
Focal length
G1 1 73.48
G2 13 47.81
G3 21 -81.77
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.956
Conditional expression (2) f2 / (-f3) = 0.585
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.672
Conditional expression (4) f / f1 = 0.702
Conditional expression (5) f / f2 = 1.079
Conditional expression (6) f1 / f2 = 1.537
Conditional expression (7) BFa / f = 0.243
Conditional expression (8) fF / fR = 0.773
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.282
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.879
Conditional expression (11) FNO × (f1 / f) = 2.640
Conditional expression (12) 2ω = 46.0

FIG. 8A is an aberration diagram at infinity focusing of the optical system according to the fourth embodiment. FIG. 8B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the fourth embodiment. From each aberration diagram, it can be seen that the optical system according to the fourth embodiment has various aberrations corrected well and has excellent imaging performance.

(Fifth Example)
A fifth embodiment will be described with reference to FIGS. 9 to 10 and Table 5. FIG. 9 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the fifth embodiment of the present embodiment. In the optical system LS (5) according to the fifth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a junction lens consisting of a biconcave first negative lens L11 arranged in order from the object side and a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and a concave surface on the object side. It consists of a meniscus-shaped second positive lens L13, a meniscus-shaped third positive lens L14 with a convex surface facing the object side, a biconvex fourth positive lens L15, and a biconcave second negative lens L16. It is composed of a bonded lens and an aperture aperture S. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a meniscus-shaped lens L22 having a concave surface facing the object side, arranged in order from the object side. It is composed of a second positive lens L23. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is a junction lens composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped first negative lens L32 having a concave surface facing the object side, arranged in order from the object side, and an object. It is composed of a second negative lens L33 having a flat concave shape with a concave surface facing to the side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 5 below lists the values of the specifications of the optical system according to the fifth embodiment. The thirteenth surface is a virtual surface.

(Table 5)
[Overall specifications]
f 51.61
FNO 1.85
ω 22.8
Y 21.70
TL 94.298
BF 13.104
BFa 12.558
[Lens specifications]
Surface number RD nd νd
1 -55.81981 2.351 1.67270 32.2
2 40.92718 3.030 1.94595 18.0
3 73.81686 2.866
4-2179.29960 8.923 1.75500 52.3
5 -55.86755 0.100
6 * 31.91227 0.300 1.56093 36.6
7 33.62812 5.941 1.80400 46.6
8 179.47342 0.200
9 31.36834 7.114 1.59319 67.9
10 -117.41333 1.500 1.67270 32.2
11 20.83074 5.078
12 ∞ D12 (variable) (aperture S)
13 ∞ 2.700
14 -23.88176 1.100 1.64769 33.7
15 -464.00395 0.306
16 * 107.59212 4.886 1.77377 47.2
17 * -34.57866 3.604
18 -87.29087 6.386 1.49782 82.6
19 -24.79412 D19 (variable)
20 -168.93770 2.949 1.94595 18.0
21 -62.61109 1.900 1.62004 36.4
22 -408.98106 2.897
23 -49.70122 1.900 1.64769 33.7
24 ∞ 10.500
25 ∞ 1.600 1.51680 64.1
26 ∞ D26 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -9.25285E-07, A6 = -2.44172E-10, A8 = -5.83429E-13, A10 = 9.84913E-16
16th surface κ = 1.0000
A4 = 2.83184E-06, A6 = 1.30771E-08, A8 = 3.97727E-11, A10 = 2.50432E-13
Surface 17 κ = 1.0000
A4 = 1.51803E-05, A6 = 3.07472E-08, A8 = -2.44486E-11, A10 = 5.97193E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.61 β = -0.1566
D0 ∞ 305.70
D12 10.295 2.359
D19 4.868 12.804
D26 1.004 1.004
[Lens group data]
Focal length
G1 1 74.25
G2 13 47.70
G3 20 -83.87
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=1.082
Conditional expression (2) f2 / (-f3) = 0.569
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.752
Conditional expression (4) f / f1 = 0.695
Conditional expression (5) f / f2 = 1.082
Conditional expression (6) f1 / f2 = 1.556
Conditional expression (7) BFa / f = 0.243
Conditional expression (8) fF / fR = 0.805
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.139
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.883
Conditional expression (11) FNO × (f1 / f) = 2.668
Conditional expression (12) 2ω = 45.6

FIG. 10A is a diagram of various aberrations of the optical system according to the fifth embodiment at infinity focusing. FIG. 10B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the fifth embodiment. From each aberration diagram, it can be seen that the optical system according to the fifth embodiment has various aberrations corrected well and has excellent imaging performance.

(6th Example)
The sixth embodiment will be described with reference to FIGS. 11 to 12 and Table 6. FIG. 11 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the sixth embodiment of the present embodiment. In the optical system LS (6) according to the sixth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 is a junction lens composed of a biconcave first negative lens L11 arranged in order from the object side, a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and a biconvex first lens group G1. A junction lens consisting of a 2 positive lens L13, a meniscus-shaped 3rd positive lens L14 with a convex surface facing the object side, a biconvex 4th positive lens L15, and a biconcave 2nd negative lens L16, and an aperture aperture. It is composed of S and. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 includes a biconcave negative lens L21, a biconvex first positive lens L22, and a meniscus-shaped second positive lens L23 with a concave surface facing the object side, which are arranged in order from the object side. , Consists of. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is a junction lens composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped first negative lens L32 having a concave surface facing the object side, arranged in order from the object side, and an object. It is composed of a second negative lens L33 having a flat concave shape with a concave surface facing to the side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 6 below lists the values of the specifications of the optical system according to the sixth embodiment. The thirteenth surface is a virtual surface.

(Table 6)
[Overall specifications]
f 51.61
FNO 1.85
ω 22.7
Y 21.70
TL 94.879
BF 13.103
BFa 12.558
[Lens specifications]
Surface number RD nd νd
1 -59.41700 3.521 1.67270 32.2
2 39.22460 3.028 1.94595 18.0
3 67.63630 2.963
4 3381.87660 8.656 1.75500 52.3
5 -56.77477 0.200
6 * 32.10469 0.100 1.56093 36.6
7 32.39825 5.977 1.77250 49.6
8 150.72327 0.200
9 29.50426 7.110 1.59319 67.9
10 -150.81319 1.500 1.64769 33.7
11 20.38598 5.145
12 ∞ D12 (variable) (aperture S)
13 ∞ 2.700
14 -23.88655 1.100 1.64769 33.7
15 11241.53800 0.200
16 * 115.09348 4.892 1.77377 47.2
17 * -33.45446 3.784
18 -154.31773 6.454 1.49782 82.6
19 -26.83890 D19 (variable)
20 -99.15080 2.941 1.94595 18.0
21 -50.06903 1.900 1.60342 38.0
22 -157.80139 2.610
23 -45.69693 1.900 1.64769 33.7
24 -615.80945 10.500
25 ∞ 1.600 1.51680 64.1
26 ∞ D26 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -7.49375E-07, A6 = -1.64453E-10, A8 = -6.263627E-13, A10 = 1.37024E-15
16th surface κ = 1.0000
A4 = 4.71706E-08, A6 = 1.49836E-08, A8 = 4.37655E-13, A10 = 2.84793E-13
Surface 17 κ = 1.0000
A4 = 1.11172E-05, A6 = 3.11358E-08, A8 = -9.41425E-11, A10 = 7.16057E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.61 β = -0.1560
D0 ∞ 305.12
D12 10.330 2.348
D19 4.563 12.545
D26 1.003 1.005
[Lens group data]
Focal length
G1 1 71.11
G2 13 47.97
G3 20 -83.32
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=1.151
Conditional expression (2) f2 / (-f3) = 0.576
Conditional expressions (3), (3-1), (3-2)
(-G1R1) / f1 = 0.836
Conditional expression (4) f / f1 = 0.726
Conditional expression (5) f / f2 = 1.076
Conditional expression (6) f1 / f2 = 1.482
Conditional expression (7) BFa / f = 0.243
Conditional expression (8) fF / fR = 0.731
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.065
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.886
Conditional expression (11) FNO × (f1 / f) = 2.555
Conditional expression (12) 2ω = 45.4

FIG. 12A is a diagram of various aberrations of the optical system according to the sixth embodiment at infinity focusing. FIG. 12B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the sixth embodiment. From each aberration diagram, it can be seen that the optical system according to the sixth embodiment has various aberrations corrected well and has excellent imaging performance.

(7th Example)
A seventh embodiment will be described with reference to FIGS. 13 to 14 and Table 7. FIG. 13 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the seventh embodiment of the present embodiment. In the optical system LS (7) according to the seventh embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a junction lens consisting of a biconcave first negative lens L11 arranged in order from the object side and a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and a concave surface on the object side. It consists of a meniscus-shaped second positive lens L13, a meniscus-shaped third positive lens L14 with a convex surface facing the object side, a biconvex fourth positive lens L15, and a biconcave second negative lens L16. It is composed of a bonded lens and an aperture aperture S. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 includes a biconcave negative lens L21, a biconvex first positive lens L22, and a meniscus-shaped second positive lens L23 with a concave surface facing the object side, which are arranged in order from the object side. , Consists of. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is a junction lens composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped first negative lens L32 having a concave surface facing the object side, arranged in order from the object side, and an object. It is composed of a second negative lens L33 having a flat concave shape with a concave surface facing to the side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 7 below lists the values of the specifications of the optical system according to the seventh embodiment. The thirteenth surface is a virtual surface.

(Table 7)
[Overall specifications]
f 51.60
FNO 1.85
ω 23.0
Y 21.70
TL 92.606
BF 13.099
BFa 12.554
[Lens specifications]
Surface number RD nd νd
1 -45.97401 3.464 1.67270 32.2
2 49.61070 3.386 1.94595 18.0
3 104.71966 2.977
4-171.07801 4.990 1.72916 54.6
5 -45.04067 0.200
6 * 34.58722 0.100 1.56093 36.6
7 35.08925 6.046 1.80400 46.6
8 271.36284 0.200
9 30.75373 7.301 1.59319 67.9
10 -109.57751 1.500 1.64769 33.7
11 21.09749 5.107
12 ∞ D12 (variable) (aperture S)
13 ∞ 2.700
14 -23.42611 1.100 1.64769 33.7
15 1293.83890 0.200
16 * 96.25206 5.000 1.77377 47.2
17 * -33.63182 2.984
18 -84.68095 6.400 1.49782 82.6
19 -24.24361 D19 (variable)
20 -198.33414 2.923 1.94595 18.0
21 -66.60448 2.000 1.64769 33.7
22 -1255.72680 2.962
23 -53.07631 2.000 1.64769 33.7
24 ∞ 10.500
25 ∞ 1.600 1.51680 64.1
26 ∞ D26 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -9.44039E-07, A6 = -7.11276E-10, A8 = 1.77477E-12, A10 = -1.49090E-15
16th surface κ = 1.0000
A4 = -7.09863E-07, A6 = 1.39281E-08, A8 = -7.11118E-11, A10 = -9.85203E-14
Surface 17 κ = 1.0000
A4 = 1.29000E-05, A6 = 1.77000E-08, A8 = 4.64016E-11, A10 = -4.30856E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.60 β = -0.1564
D0 ∞ 307.39
D12 10.322 2.393
D19 5.645 13.574
D26 0.999 0.999
[Lens group data]
Focal length
G1 1 73.64
G2 13 48.40
G3 20 -83.16
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.891
Conditional expression (2) f2 / (-f3) = 0.582
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.624
Conditional expression (4) f / f1 = 0.701
Conditional expression (5) f / f2 = 1.066
Conditional expression (6) f1 / f2 = 1.522
Conditional expression (7) BFa / f = 0.243
Conditional expression (8) fF / fR = 0.769
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.390
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.883
Conditional expression (11) FNO × (f1 / f) = 2.646
Conditional expression (12) 2ω = 46.0

FIG. 14A is a diagram of various aberrations of the optical system according to the seventh embodiment when the optical system is in focus at infinity. FIG. 14B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the seventh embodiment. From each aberration diagram, it can be seen that the optical system according to the seventh embodiment has various aberrations corrected well and has excellent imaging performance.

(8th Example)
The eighth embodiment will be described with reference to FIGS. 15 to 16 and Table 8. FIG. 15 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the eighth embodiment of the present embodiment. In the optical system LS (8) according to the eighth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a junction lens consisting of a biconcave first negative lens L11 arranged in order from the object side and a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and a concave surface on the object side. It consists of a meniscus-shaped second positive lens L13, a meniscus-shaped third positive lens L14 with a convex surface facing the object side, a biconvex fourth positive lens L15, and a biconcave second negative lens L16. It is composed of a bonded lens and an aperture aperture S. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 includes a biconcave negative lens L21, a biconvex first positive lens L22, and a meniscus-shaped second positive lens L23 with a concave surface facing the object side, which are arranged in order from the object side. , Consists of. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is a junction lens composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped first negative lens L32 having a concave surface facing the object side, arranged in order from the object side, and an object. It is composed of a second negative lens L33 having a flat concave shape with a concave surface facing to the side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 8 below lists the values of the specifications of the optical system according to the eighth embodiment. The thirteenth surface is a virtual surface.

(Table 8)
[Overall specifications]
f 51.60
FNO 1.85
ω 22.9
Y 21.70
TL 93.035
BF 13.101
BFa 12.556
[Lens specifications]
Surface number RD nd νd
1 -49.74101 3.508 1.67270 32.2
2 51.83840 3.342 1.94595 18.0
3 105.00000 2.890
4 -198.79923 5.698 1.72916 54.6
5 -48.74109 0.216
6 * 39.85460 0.100 1.56093 36.6
7 39.94369 5.459 1.80400 46.6
8 306.55979 0.200
9 27.39919 7.979 1.59319 67.9
10 -244.36823 1.500 1.64769 33.7
11 21.09582 5.098
12 ∞ D12 (variable) (aperture S)
13 ∞ 2.700
14 -23.37434 1.100 1.64769 33.7
15 630.74141 0.200
16 * 88.88240 5.000 1.77377 47.2
17 * -34.54296 2.466
18 -91.09112 6.400 1.49782 82.6
19 -24.26835 D19 (variable)
20 -173.73017 2.915 1.94595 18.0
21 -63.36086 2.000 1.64769 33.7
22 -410.38800 2.872
23 -49.55593 1.900 1.64769 33.7
24 ∞ 10.500
25 ∞ 1.600 1.51680 64.1
26 ∞ D26 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -1.98971E-07, A6 = -9.88462E-10, A8 = 4.89667E-12, A10 = -4.46361E-15
16th surface κ = 1.0000
A4 = -1.30154E-06, A6 = 1.97109E-08, A8 = -1.12019E-10, A10 = -2.74309E-14
Surface 17 κ = 1.0000
A4 = 1.29000E-05, A6 = 1.77000E-08, A8 = 4.40194E-11, A10 = -4.63161E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.60 β = -0.1566
D0 ∞ 306.96
D12 10.321 2.394
D19 6.070 13.997
D26 1.000 1.000
[Lens group data]
Focal length
G1 1 73.37
G2 13 48.59
G3 20 -81.56
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=0.964
Conditional expression (2) f2 / (-f3) = 0.596
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.678
Conditional expression (4) f / f1 = 0.703
Conditional expression (5) f / f2 = 1.062
Conditional expression (6) f1 / f2 = 1.510
Conditional expression (7) BFa / f = 0.243
Conditional expression (8) fF / fR = 0.747
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.357
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.885
Conditional expression (11) FNO × (f1 / f) = 2.636
Conditional expression (12) 2ω = 45.8

FIG. 16A is an aberration diagram at infinity focusing of the optical system according to the eighth embodiment. FIG. 16B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the eighth embodiment. From each aberration diagram, it can be seen that the optical system according to the eighth embodiment has various aberrations corrected well and has excellent imaging performance.

(9th Example)
A ninth embodiment will be described with reference to FIGS. 17-18 and Table 9. FIG. 17 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the ninth embodiment of the present embodiment. In the optical system LS (9) according to the ninth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a junction lens consisting of a biconcave first negative lens L11 arranged in order from the object side and a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and a concave surface on the object side. It consists of a meniscus-shaped second positive lens L13, a meniscus-shaped third positive lens L14 with a convex surface facing the object side, a biconvex fourth positive lens L15, and a biconcave second negative lens L16. It is composed of a bonded lens and an aperture aperture S. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 includes a biconcave negative lens L21, a biconvex first positive lens L22, and a meniscus-shaped second positive lens L23 with a concave surface facing the object side, which are arranged in order from the object side. , Consists of. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is a junction lens composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped first negative lens L32 having a concave surface facing the object side, arranged in order from the object side, and an object. It is composed of a second negative lens L33 having a flat concave shape with a concave surface facing to the side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 9 below lists the values of the specifications of the optical system according to the ninth embodiment. The thirteenth surface is a virtual surface.

(Table 9)
[Overall specifications]
f 51.60
FNO 1.85
ω 22.9
Y 21.70
TL 92.330
BF 13.100
BFa 12.554
[Lens specifications]
Surface number RD nd νd
1 -48.06457 2.000 1.67270 32.2
2 50.03333 2.861 1.94595 18.0
3 105.00000 2.805
4-226.31231 6.827 1.72916 54.6
5 -47.98013 0.644
6 * 36.64910 0.100 1.56093 36.6
7 36.85687 5.622 1.80400 46.6
8 217.92780 0.200
9 28.49361 7.332 1.59319 67.9
10 -161.37986 1.500 1.64769 33.7
11 20.99038 5.164
12 ∞ D12 (variable) (aperture S)
13 ∞ 2.700
14 -23.41799 1.100 1.64769 33.7
15 998.77224 0.200
16 * 85.12299 5.000 1.77377 47.2
17 * -35.29338 2.485
18 -73.80381 6.400 1.49782 82.6
19 -23.23519 D19 (variable)
20 -177.75440 2.927 1.94595 18.0
21 -63.69645 1.900 1.64769 33.7
22 -482.01125 2.887
23 -50.20764 1.900 1.64769 33.7
24 ∞ 10.500
25 ∞ 1.600 1.51680 64.1
26 ∞ D26 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -4.74106E-07, A6 = -3.40824E-10, A8 = 2.15394E-12, A10 = -1.54492E-15
16th surface κ = 1.0000
A4 = -1.95205E-07, A6 = 1.94342E-08, A8 = -8.61846E-11, A10 = -2.07763E-13
Surface 17 κ = 1.0000
A4 = 1.47643E-05, A6 = 2.08671E-08, A8 = 8.44852E-11, A10 = -6.93210E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.60 β = -0.1565
D0 ∞ 307.67
D12 10.320 2.409
D19 6.356 14.267
D26 1.000 1.000
[Lens group data]
Focal length
G1 1 73.63
G2 13 48.76
G3 20 -81.76
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=0.964
Conditional expression (2) f2 / (-f3) = 0.596
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.676
Conditional expression (4) f / f1 = 0.701
Conditional expression (5) f / f2 = 1.058
Conditional expression (6) f1 / f2 = 1.510
Conditional expression (7) BFa / f = 0.243
Conditional expression (8) fF / fR = 0.748
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.357
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.888
Conditional expression (11) FNO × (f1 / f) = 2.645
Conditional expression (12) 2ω = 45.8

FIG. 18A is an aberration diagram at infinity focusing of the optical system according to the ninth embodiment. FIG. 18B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the ninth embodiment. From each aberration diagram, it can be seen that the optical system according to the ninth embodiment has various aberrations corrected well and has excellent imaging performance.

(10th Example)
The tenth embodiment will be described with reference to FIGS. 19 to 20 and Table 10. FIG. 19 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the tenth embodiment of the present embodiment. In the optical system LS (10) according to the tenth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a junction lens consisting of a biconcave first negative lens L11 arranged in order from the object side and a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and a concave surface on the object side. It consists of a meniscus-shaped second positive lens L13, a meniscus-shaped third positive lens L14 with a convex surface facing the object side, a biconvex fourth positive lens L15, and a biconcave second negative lens L16. It is composed of a bonded lens and an aperture aperture S. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 includes a biconcave negative lens L21, a biconvex first positive lens L22, and a meniscus-shaped second positive lens L23 with a concave surface facing the object side, which are arranged in order from the object side. , Consists of. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is a junction lens composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped first negative lens L32 having a concave surface facing the object side, arranged in order from the object side, and an object. It is composed of a second negative lens L33 having a flat concave shape with a concave surface facing to the side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 10 below lists the values of the specifications of the optical system according to the tenth embodiment. The thirteenth surface is a virtual surface.

(Table 10)
[Overall specifications]
f 51.61
FNO 1.85
ω 23.0
Y 21.70
TL 92.630
BF 13.111
BFa 12.566
[Lens specifications]
Surface number RD nd νd
1 -47.48420 2.000 1.67270 32.2
2 49.34200 2.900 1.94595 18.0
3 105.06869 2.850
4-214.61709 6.650 1.72916 54.6
5 -47.45376 0.640
6 * 36.92032 0.100 1.56093 36.6
7 37.08029 5.650 1.80400 46.6
8 227.67817 0.250
9 28.81243 7.400 1.59319 67.9
10 -141.32000 1.500 1.64769 33.7
11 21.19231 5.130
12 ∞ D12 (variable) (aperture S)
13 ∞ 2.700
14 -23.47056 1.100 1.64769 33.7
15 682.91466 0.200
16 * 83.29512 5.000 1.77377 47.2
17 * -35.02672 2.570
18 -71.96528 6.400 1.49782 82.6
19 -23.20263 D19 (variable)
20 -192.79576 2.950 1.94595 18.0
21 -65.62300 2.000 1.64769 33.7
22 -664.53730 2.909
23 -51.20031 1.900 1.64769 33.7
24 ∞ 10.500
25 ∞ 1.600 1.51680 64.1
26 ∞ D26 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -4.82693E-07, A6 = -2.32147E-10, A8 = 1.82978E-12, A10 = -1.19713E-15
16th surface κ = 1.0000
A4 = -2.777465E-07, A6 = 1.84476E-08, A8 = -7.60811E-11, A10 = -2.05509E-13
Surface 17 κ = 1.0000
A4 = 1.46947E-05, A6 = 2.13572E-08, A8 = 8.25934E-11, A10 =-6.58549E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.61 β = -0.1568
D0 ∞ 307.37
D12 10.320 2.403
D19 6.400 14.317
D26 1.011 1.011
[Lens group data]
Focal length
G1 1 74.30
G2 13 48.80
G3 20 -82.85
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=0.920
Conditional expression (2) f2 / (-f3) = 0.589
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.639
Conditional expression (4) f / f1 = 0.695
Conditional expression (5) f / f2 = 1.058
Conditional expression (6) f1 / f2 = 1.523
Conditional expression (7) BFa / f = 0.243
Conditional expression (8) fF / fR = 0.768
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.377
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.890
Conditional expression (11) FNO × (f1 / f) = 2.670
Conditional expression (12) 2ω = 46.0

FIG. 20A is a diagram of various aberrations of the optical system according to the tenth embodiment at infinity focusing. FIG. 20B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the tenth embodiment. From each aberration diagram, it can be seen that the optical system according to the tenth embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(11th Example)
The eleventh embodiment will be described with reference to FIGS. 21 to 22 and Table 11. FIG. 21 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the eleventh embodiment of the present embodiment. In the optical system LS (11) according to the eleventh embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a biconcave second negative lens L12, and a meniscus-shaped first positive lens L13 with a convex surface facing the object side. A junction lens consisting of a biconvex second positive lens L14, a biconvex third positive lens L15, a biconvex fourth positive lens L16, and a biconcave third negative lens L17. It is composed of a lens and an aperture aperture S. The third positive lens L15 has an aspherical lens surface on the object side.

The second lens group G2 includes a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a biconvex second positive lens L23 arranged in order from the object side. , Consists of. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a convex surface facing the object side and a meniscus-shaped negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. The negative lens L32 has an aspherical lens surface on the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 11 below lists the values of the specifications of the optical system according to the eleventh embodiment. The 14th surface is a virtual surface.

(Table 11)
[Overall specifications]
f 37.63
FNO 1.85
ω 30.0
Y 21.70
TL 110.000
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 -662.83160 3.000 1.80920 33.6
2 33.87219 9.404
3-109.33916 3.000 1.48749 70.4
4 89.77072 4.000 1.94595 18.0
5 317.57072 1.945
6 44.26915 8.500 1.48749 70.4
7 -112.47821 3.972
8 * 41.20576 6.500 1.80400 46.6
9 -255.27183 0.200
10 26.75656 9.000 1.59319 67.9
11 -57.15784 1.500 1.67270 32.2
12 17.14008 5.399
13 ∞ D13 (variable) (aperture S)
14 ∞ 3.000
15-21.57444 1.000 1.67270 32.2
16 -1291.14570 0.200
17 * 157.44017 4.500 1.77377 47.2
18 * -44.84339 0.200
19 155.77289 9.000 1.59319 67.9
20 -25.32306 D20 (variable)
21 71.98835 3.000 1.94595 18.0
22 81.46254 6.736
23 * -41.56282 1.500 1.64769 33.7
24-168.89768 7.000
25 ∞ 1.600 1.51680 64.1
26 ∞ D26 (variable)
[Aspherical data]
Side 8 κ = 1.0000
A4 = -1.90145E-06, A6 = -9.52591E-10, A8 = -1.08708E-12, A10 = -6.77034E-16
Surface 17 κ = 1.0000
A4 = 6.23513E-06, A6 = -1.23942E-08, A8 = 3.34827E-11, A10 = -3.01713E-13
Surface 18 κ = 1.0000
A4 = 1.88293E-05, A6 = 1.24857E-08, A8 = 2.84962E-11, A10 = -3.23051E-13
Side 23 κ = 1.0000
A4 = 5.43854E-06, A6 = -1.52554E-08, A8 = 0.00000E + 00, A10 = 0.00000E + 00
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 37.63 β = -0.2078
D0 ∞ 151.72
D13 11.387 2.404
D20 3.456 12.439
D26 1.000 1.000
[Lens group data]
Focal length
G1 1 58.79
G2 14 43.00
G3 21 -104.59
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=17.613
Conditional expression (2) f2 / (-f3) = 0.411
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=11.275
Conditional expression (4) f / f1 = 0.640
Conditional expression (5) f / f2 = 0.875
Conditional expression (6) f1 / f2 = 1.637
Conditional expression (7) BFa / f = 0.241
Conditional expression (8) fF / fR = 0.945
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) =-0.903
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.728
Conditional expression (11) FNO × (f1 / f) = 2.893
Conditional expression (12) 2ω = 60.0

FIG. 22A is a diagram of various aberrations of the optical system according to the eleventh embodiment at infinity focusing. FIG. 22B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the eleventh embodiment. From each aberration diagram, it can be seen that the optical system according to the eleventh embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(12th Example)
A twelfth embodiment will be described with reference to FIGS. 23 to 24 and Table 12. FIG. 23 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the twelfth embodiment of the present embodiment. In the optical system LS (12) according to the twelfth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a biconcave second negative lens L12, and a meniscus-shaped first positive lens L13 with a convex surface facing the object side. A junction lens consisting of a biconvex second positive lens L14, a biconvex third positive lens L15, a biconvex fourth positive lens L16, and a biconcave third negative lens L17. It is composed of a lens and an aperture aperture S. The third positive lens L15 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a meniscus-shaped first positive lens L22 having a concave surface facing the object side, and a biconvex lens arranged in order from the object side. It is composed of a second positive lens L23 and a meniscus-shaped third positive lens L24 with a concave surface facing the object side. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. The negative lens L32 has an aspherical lens surface on the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 12 below lists the values of the specifications of the optical system according to the twelfth embodiment. The 14th surface is a virtual surface.

(Table 12)
[Overall specifications]
f 37.70
FNO 1.88
ω 30.0
Y 21.70
TL 110.000
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 -3112.32120 3.000 1.73282 32.6
2 32.68764 8.690
3-440.00413 3.000 1.48749 70.4
4 57.93171 4.000 1.94595 18.0
5 108.74454 3.168
6 42.60783 8.500 1.50267 62.2
7 -141.78756 3.866
8 * 45.06258 6.500 1.80400 46.6
9 -210.82291 0.200
10 36.02017 9.000 1.59319 67.9
11 -45.79266 1.500 1.67270 32.2
12 22.46589 5.399
13 ∞ D13 (variable) (aperture S)
14 ∞ 3.000
15 -22.15003 1.000 1.67270 32.2
16 -98.33346 0.318
17 * -130.89892 2.500 1.77377 47.2
18 * -43.35291 1.224
19 101.79100 5.500 1.59319 67.9
20 -53.62571 0.100
21 -81.82793 6.000 1.59319 67.9
22 -25.48031 D22 (variable)
23 -75.16977 3.000 1.94595 18.0
24-63.16701 8.776
25 * -25.51533 1.500 1.64769 33.7
26 -99.50792 7.000
27 ∞ 1.600 1.51680 64.1
28 ∞ D28 (variable)
[Aspherical data]
Side 8 κ = 1.0000
A6 = -1.62936E-06, A6 = -1.61898E-09, A8 = 3.72851E-12, A10 = -6.56781E-15
Surface 17 κ = 1.0000
A4 = 3.15178E-05, A6 = 1.77790E-07, A8 = -3.27517E-10, A10 = -1.26227E-12
Surface 18 κ = 1.0000
A4 = 4.17433E-05, A6 = 1.91618E-07, A8 = 1.40927E-10, A10 = -2.86119E-12
Side 25 κ = 1.0000
A4 = 1.10584E-05, A6 = -1.56481E-10, A8 = 0.00000E + 00, A10 = 0.00000E + 00
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 37.70 β = -0.1179
D0 ∞ 290.00
D13 6.605 2.441
D22 4.053 8.217
D28 1.000 1.000
[Lens group data]
Focal length
G1 1 63.38
G2 14 39.22
G3 23 -62.57
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=82.547
Conditional expression (2) f2 / (-f3) = 0.627
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=49.101
Conditional expression (4) f / f1 = 0.595
Conditional expression (5) f / f2 = 0.961
Conditional expression (6) f1 / f2 = 1.616
Conditional expression (7) BFa / f = 0.240
Conditional expression (8) fF / fR = 0.873
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) =-0.979
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.994
Conditional expression (11) FNO × (f1 / f) = 3.160
Conditional expression (12) 2ω = 60.0

FIG. 24A is a diagram of various aberrations of the optical system according to the twelfth embodiment at infinity focusing. FIG. 24B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the twelfth embodiment. From each aberration diagram, it can be seen that the optical system according to the twelfth embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(13th Example)
The thirteenth embodiment will be described with reference to FIGS. 25 to 26 and Table 13. FIG. 25 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the thirteenth embodiment of the present embodiment. In the optical system LS (13) according to the thirteenth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a biconcave second negative lens L12, and a meniscus-shaped first positive lens L13 with a convex surface facing the object side. A junction lens consisting of a biconvex second positive lens L14, a biconvex third positive lens L15, a biconvex fourth positive lens L16, and a biconcave third negative lens L17. It is composed of a lens and an aperture aperture S. The third positive lens L15 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a meniscus-shaped first positive lens L22 having a concave surface facing the object side, and a biconvex lens arranged in order from the object side. It is composed of a second positive lens L23 and a meniscus-shaped third positive lens L24 with a concave surface facing the object side. The first positive lens L22 has an aspherical lens surface on the object side.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a convex surface facing the object side and a meniscus-shaped negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. The negative lens L32 has an aspherical lens surface on the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 13 below lists the values of the specifications of the optical system according to the thirteenth embodiment. The 14th surface is a virtual surface.

(Table 13)
[Overall specifications]
f 36.52
FNO 1.85
ω 30.6
Y 21.70
TL 100.000
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 -344.23276 3.000 1.71736 29.6
2 31.47663 8.864
3 -5197.94500 3.000 1.48749 70.3
4 59.50193 4.000 1.94595 18.0
5 141.00357 0.152
6 49.20783 7.500 1.60300 65.4
7 -563.87665 4.981
8 * 39.11480 6.000 1.77250 49.6
9 -139.68211 0.427
10 28.58681 8.000 1.59319 67.9
11 -50.06370 1.500 1.67270 32.2
12 19.18437 5.399
13 ∞ D13 (variable) (aperture S)
14 ∞ 3.000
15 -22.50724 1.000 1.67270 32.2
16 -81.31951 0.549
17 * -74.31824 3.000 1.77377 47.2
18 -35.67165 0.203
19 180.93759 5.000 1.59319 67.9
20 -43.85092 0.500
21 -132.62507 6.000 1.59319 67.9
22 -29.07561 D22 (variable)
23 317.64282 3.000 1.94595 18.0
24 314.90339 6.932
25 * -26.84153 1.500 1.64769 33.7
26 -77.55848 7.000
27 ∞ 1.600 1.51680 64.1
28 ∞ D28 (variable)
[Aspherical data]
Side 8 κ = 1.0000
A4 = -1.59558E-06, A6 = -1.61180E-09, A8 = 2.67206E-12, A10 = -4.02129E-15
Surface 17 κ = 1.0000
A4 = -1.62012E-05, A6 = -2.42502E-08, A8 = 1.25145E-10, A10 = -1.02694E-12
Side 25 κ = 1.0000
A4 = 7.25982E-06, A6 = 1.79235E-08, A8 = -4.70327E-11, A10 = 2.68072E-14
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 36.52 β = -0.1131
D0 ∞ 290.00
D13 6.346 1.987
D22 0.549 4.907
D28 1.000 1.000
[Lens group data]
Focal length
G1 1 52.27
G2 14 37.19
G3 23 -64.36
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=9.427
Conditional expression (2) f2 / (-f3) = 0.578
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=6.586
Conditional expression (4) f / f1 = 0.699
Conditional expression (5) f / f2 = 0.982
Conditional expression (6) f1 / f2 = 1.406
Conditional expression (7) BFa / f = 0.248
Conditional expression (8) fF / fR = 0.724
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = -0.832
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.853
Conditional expression (11) FNO × (f1 / f) = 2.645
Conditional expression (12) 2ω = 61.2

FIG. 26A is a diagram of various aberrations of the optical system according to the thirteenth embodiment at infinity focusing. FIG. 26B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the thirteenth embodiment. From each aberration diagram, it can be seen that the optical system according to the thirteenth embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(14th Example)
The 14th embodiment will be described with reference to FIGS. 27 to 28 and Table 14. FIG. 27 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 14th embodiment of the present embodiment. In the optical system LS (14) according to the 14th embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a meniscus-shaped second negative lens L12 with a convex surface facing the object side, and a meniscus shape with a convex surface facing the object side. A junction lens composed of the first positive lens L13, a meniscus-shaped second positive lens L14 with a convex surface facing the object side, a biconvex third positive lens L15, a biconvex fourth positive lens L16, and It is composed of a junction lens made of a biconcave third negative lens L17 and an aperture aperture S. The third positive lens L15 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a meniscus-shaped first positive lens L22 having a concave surface facing the object side, and a biconvex lens arranged in order from the object side. It is composed of a second positive lens L23 and a meniscus-shaped third positive lens L24 with a concave surface facing the object side. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a convex surface facing the object side and a meniscus-shaped negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. The negative lens L32 has an aspherical lens surface on the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 14 below lists the values of the specifications of the optical system according to the 14th embodiment. The 14th surface is a virtual surface.

(Table 14)
[Overall specifications]
f 36.50
FNO 1.85
ω 30.7
Y 21.70
TL 100.000
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 -328.51209 3.000 1.71736 29.6
2 30.62735 8.724
3 862.45645 3.000 1.48749 70.3
4 57.42336 4.000 1.94595 18.0
5 141.63170 0.100
6 44.98135 7.500 1.60300 65.4
7 5539.31740 5.241
8 * 41.34810 6.000 1.77250 49.6
9 -119.73719 0.200
10 28.47480 8.000 1.59319 67.9
11 -45.24565 1.500 1.67270 32.2
12 19.20206 5.399
13 ∞ D13 (variable) (aperture S)
14 ∞ 3.000
15 -23.51305 1.000 1.67270 32.2
16 -129.15388 0.457
17 * -103.44705 3.000 1.77377 47.2
18 * -39.20704 0.417
19 131.40567 5.000 1.59319 67.9
20 -48.12075 0.500
21 -100.00000 6.000 1.59319 67.9
22 -26.83541 D22 (variable)
23 102.68371 3.000 1.94595 18.0
24 106.30512 6.996
25 * -28.73049 1.500 1.64769 33.7
26 -98.04242 7.000
27 ∞ 1.600 1.51680 64.1
28 ∞ D28 (variable)
[Aspherical data]
Side 8 κ = 1.0000
A4 = -1.74572E-06, A6 = -1.86902E-09, A8 = 3.70243E-12, A10 = -5.65794E-15
Surface 17 κ = 1.0000
A4 = -4.49752E-06, A6 = -4.35264E-08, A8 = 1.70129E-10, A10 = -7.71012E-13
Surface 18 κ = 1.0000
A4 = 1.06552E-05, A6 = 0.00000E + 00, A8 = 0.00000E + 00, A10 = 0.00000E + 00
Side 25 κ = 1.0000
A4 = 6.97711E-06, A6 = 8.30426E-09, A8 = -3.04728E-11, A10 = -2.65514E-15
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 36.50 β = -0.1131
D0 ∞ 290.00
D13 6.366 1.830
D22 0.500 5.036
D28 1.000 1.000
[Lens group data]
Focal length
G1 1 52.56
G2 14 38.05
G3 23 -66.26
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=9.000
Conditional expression (2) f2 / (-f3) = 0.574
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=6.250
Conditional expression (4) f / f1 = 0.694
Conditional expression (5) f / f2 = 0.959
Conditional expression (6) f1 / f2 = 1.381
Conditional expression (7) BFa / f = 0.248
Conditional expression (8) fF / fR = 0.729
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = -0.829
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.815
Conditional expression (11) FNO × (f1 / f) = 2.664
Conditional expression (12) 2ω = 61.4

FIG. 28A is an aberration diagram of the optical system according to the 14th embodiment at infinity focusing. FIG. 28B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 14th embodiment. From each aberration diagram, it can be seen that the optical system according to the 14th embodiment has various aberrations corrected well and has excellent imaging performance.

(15th Example)
A fifteenth embodiment will be described with reference to FIGS. 29 to 30 and Table 15. FIG. 29 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the fifteenth embodiment of the present embodiment. In the optical system LS (15) according to the fifteenth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a meniscus-shaped second negative lens L12 with a convex surface facing the object side, and a meniscus shape with a convex surface facing the object side. A junction lens composed of the first positive lens L13, a biconvex second positive lens L14, a biconvex third positive lens L15, a biconvex fourth positive lens L16, and a biconcave third. It is composed of a junction lens made of a negative lens L17 and an aperture aperture S. The third positive lens L15 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a meniscus-shaped first positive lens L22 having a concave surface facing the object side, and a biconvex lens arranged in order from the object side. It is composed of a second positive lens L23 and a meniscus-shaped third positive lens L24 with a concave surface facing the object side. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is composed of a meniscus-shaped negative lens L31 with a concave surface facing the object side. The negative lens L31 has an aspherical lens surface on the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 15 below lists the values of the specifications of the optical system according to the 15th embodiment. The 14th surface is a virtual surface.

(Table 15)
[Overall specifications]
f 36.50
FNO 1.87
ω 30.7
Y 21.70
TL 100.000
BF 9.600
BFa 9.054
[Lens specifications]
Surface number RD nd νd
1 -188.20085 3.000 1.71736 29.6
2 30.66496 8.404
3 547.03690 3.000 1.48749 70.3
4 62.69373 4.000 1.94595 18.0
5 190.11798 0.100
6 45.62385 7.500 1.60300 65.4
7 -115579.46000 5.673
8 * 44.63892 6.000 1.77250 49.6
9 -102.19551 0.200
10 28.17341 8.000 1.59319 67.9
11 -42.44281 1.500 1.67270 32.2
12 19.02911 5.399
13 ∞ D13 (variable) (aperture S)
14 ∞ 3.000
15 -23.61092 1.000 1.67270 32.2
16 -109.82047 0.899
17 * -60.75679 3.000 1.77377 47.2
18 * -33.74626 0.200
19 105.85192 5.000 1.59319 67.9
20 -52.67684 0.500
21 -100.00000 6.000 1.59319 67.9
22 -26.83541 D22 (variable)
23 * -35.17199 1.500 1.64769 33.7
24-148.75840 7.000
25 ∞ 1.600 1.51680 64.1
26 ∞ D26 (variable)
[Aspherical data]
Side 8 κ = 1.0000
A4 = -1.59317E-06, A6 = -1.58329E-09, A8 = 3.51477E-12, A10 = -5.52433E-15
Surface 17 κ = 1.0000
A4 = -1.23191E-05, A6 = -4.63629E-08, A8 = 2.30352E-10, A10 = -1.55636E-12
Surface 18 κ = 1.0000
A4 = 3.43104E-06, A6 = 0.00000E + 00, A8 = 0.00000E + 00, A10 = 0.00000E + 00
Side 23 κ = 1.0000
A4 = 2.07644E-06, A6 = 2.61568E-09, A8 = -1.43218E-11, A10 = -5.83085E-14
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 36.50 β = -0.1132
D0 ∞ 290.00
D13 6.253 1.764
D22 10.273 14.761
D28 1.000 1.000
[Lens group data]
Focal length
G1 1 52.70
G2 14 38.26
G3 23 -71.49
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=5.156
Conditional expression (2) f2 / (-f3) = 0.535
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=3.571
Conditional expression (4) f / f1 = 0.693
Conditional expression (5) f / f2 = 0.954
Conditional expression (6) f1 / f2 = 1.377
Conditional expression (7) BFa / f = 0.248
Conditional expression (8) fF / fR = 0.758
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = -0.720
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.828
Conditional expression (11) FNO × (f1 / f) = 2.696
Conditional expression (12) 2ω = 61.4

FIG. 30A is a diagram of various aberrations of the optical system according to the fifteenth embodiment at infinity focusing. FIG. 30B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the fifteenth embodiment. From each aberration diagram, it can be seen that the optical system according to the fifteenth embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(16th Example)
The sixteenth embodiment will be described with reference to FIGS. 31 to 32 and Table 16. FIG. 31 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 16th embodiment of the present embodiment. In the optical system LS (16) according to the 16th embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a meniscus-shaped second negative lens L12 with a convex surface facing the object side, and a meniscus shape with a convex surface facing the object side. A junction lens composed of the first positive lens L13, a biconvex second positive lens L14, a biconvex third positive lens L15, a biconvex fourth positive lens L16, and a biconcave third. It is composed of a junction lens made of a negative lens L17 and an aperture aperture S. The third positive lens L15 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a meniscus-shaped lens L22 having a concave surface facing the object side, arranged in order from the object side. It is composed of a second positive lens L23 and a meniscus-shaped third positive lens L24 with a concave surface facing the object side. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a convex surface facing the object side and a meniscus-shaped negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. The negative lens L32 has an aspherical lens surface on the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 16 below lists the values of the specifications of the optical system according to the 16th embodiment. The 14th surface is a virtual surface.

(Table 16)
[Overall specifications]
f 36.50
FNO 1.86
ω 30.8
Y 21.70
TL 100.000
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 -133.60683 2.000 1.71736 29.6
2 32.54620 8.076
3 388.71645 2.500 1.48749 70.3
4 65.47753 4.000 1.94595 18.0
5 219.57835 0.100
6 57.60424 7.000 1.60300 65.4
7 -387.08519 6.523
8 * 44.24367 6.000 1.77250 49.6
9 -104.52830 0.200
10 31.09490 9.000 1.59319 67.9
11 -42.99037 1.500 1.67270 32.2
12 20.68411 5.399
13 ∞ D13 (variable) (aperture S)
14 ∞ 3.000
15 -23.39527 1.000 1.67270 32.2
16 -374.05277 0.224
17 * 89.21164 4.000 1.77377 47.2
18 * -62.00927 1.388
19 -586.47623 4.500 1.59319 67.9
20 -38.88857 0.500
21 -100.00000 5.500 1.59319 67.9
22 -29.94109 D22 (variable)
23 59.66877 3.000 1.94595 18.0
24 59.44379 6.722
25 * -32.82899 1.500 1.64769 33.7
26 -177.92654 7.000
27 ∞ 1.600 1.51680 63.9
28 ∞ D28 (variable)
[Aspherical data]
Side 8 κ = 1.0000
A4 = -1.04917E-06, A6 = -1.42831E-09, A8 = 4.66129E-12, A10 = -6.33796E-15
Surface 17 κ = 1.0000
A4 = 1.65960E-05, A6 = 5.96989E-08, A6 = -6.57382E-11, A10 = 1.19611E-13
Surface 18 κ = 1.0000
A4 = 2.95825E-05, A6 = 7.91633E-08, A8 = 0.00000E + 00, A10 = 0.00000E + 00
Side 25 κ = 1.0000
A4 = 4.39415E-06, A6 = -1.10198E-08, A8 = 5.26933E-11, A10 = -1.66739E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 36.50 β = -0.1137
D0 ∞ 290.00
D13 6.258 1.649
D22 0.509 5.118
D28 1.000 1.000
[Lens group data]
Focal length
G1 1 53.58
G2 14 39.30
G3 23 -65.49
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=3.660
Conditional expression (2) f2 / (-f3) = 0.600
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=2.494
Conditional expression (4) f / f1 = 0.681
Conditional expression (5) f / f2 = 0.929
Conditional expression (6) f1 / f2 = 1.363
Conditional expression (7) BFa / f = 0.248
Conditional expression (8) fF / fR = 0.714
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) =-0.608
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.810
Conditional expression (11) FNO × (f1 / f) = 2.734
Conditional expression (12) 2ω = 61.6

FIG. 32 (A) is a diagram of various aberrations of the optical system according to the 16th embodiment at infinity focusing. FIG. 32B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the sixteenth embodiment. From each aberration diagram, it can be seen that the optical system according to the 16th embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(17th Example)
The seventeenth embodiment will be described with reference to FIGS. 33 to 34 and Table 17. FIG. 33 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 17th embodiment of the present embodiment. In the optical system LS (17) according to the 17th embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a meniscus-shaped first positive lens L12 with a convex surface facing the object side, and a meniscus with a concave surface facing the object side. A junction lens composed of a second negative lens L13 having a shape, a second positive lens L14 having a biconvex shape, a third positive lens L15 having a biconvex shape, and a third negative lens L16 having a biconcave shape, an aperture aperture S, and the like. Consists of. The second negative lens L13 has an aspherical lens surface on the image plane I side. The second positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a meniscus-shaped lens L22 having a concave surface facing the object side, arranged in order from the object side. It is composed of a second positive lens L23. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is a junction lens composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped first negative lens L32 having a concave surface facing the object side, arranged in order from the object side, and an object. It is composed of a second negative lens L33 having a flat concave shape with a concave surface facing to the side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 17 below lists the values of the specifications of the optical system according to the 17th embodiment. The thirteenth surface is a virtual surface.

(Table 17)
[Overall specifications]
f 36.05
FNO 1.85
ω 31.6
Y 21.70
TL 99.592
BF 13.100
BFa 12.555
[Lens specifications]
Surface number RD nd νd
1 -500.00000 2.000 1.59270 35.3
2 27.30135 8.716
3 60.46320 3.840 1.94594 18.0
4 220.11217 9.742
5 -29.41908 1.659 1.77377 47.2
6 * -33.35969 1.884
7 * 47.17368 10.592 1.76801 49.2
8 -60.97010 0.200
9 27.06671 6.869 1.59319 67.9
10 -38.40610 1.500 1.69895 30.1
11 22.53254 3.899
12 ∞ D12 (variable) (aperture S)
13 ∞ 2.700
14 -20.48042 1.100 1.64769 33.7
15 -452.00052 0.648
16 * 80.79578 4.788 1.77377 47.2
17 * -31.41145 0.568
18 -137.97943 6.400 1.49782 82.6
19 -21.82018 D19 (variable)
20 -72.37319 4.704 1.94594 18.0
21 -25.72015 1.900 1.80518 25.4
22 -96.08935 2.660
23 -34.82473 1.900 1.64769 33.7
24 ∞ 10.500
25 ∞ 1.600 1.51680 64.1
26 ∞ D26 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -1.02986E-07, A6 = 4.20882E-09, A8 = -1.01963E-11, A10 = 2.17897E-14
Side 7 κ = 1.0000
A4 = -2.57635E-07, A6 = 3.44388E-09, A8 = -9.56027E-12, A10 = 7.45193E-15
16th surface κ = 1.0000
A4 = -2.53184E-06, A6 = 4.68537E-08, A8 = -1.77268E-11, A10 = -7.02284E-13
Surface 17 κ = 1.0000
A4 = 2.23902E-05, A6 = 1.94868E-08, A8 = 4.29642E-10, A10 = -1.80787E-12
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 36.05 β = -0.1049
D0 ∞ 314.50
D12 5.722 2.550
D19 2.500 5.667
D26 1.000 1.000
[Lens group data]
Focal length
G1 1 49.49
G2 13 36.41
G3 20 -55.61
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=13.870
Conditional expression (2) f2 / (-f3) = 0.655
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=10.103
Conditional expression (4) f / f1 = 0.728
Conditional expression (5) f / f2 = 0.990
Conditional expression (6) f1 / f2 = 1.359
Conditional expression (7) BFa / f = 0.348
Conditional expression (8) fF / fR = 0.554
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) =-0.896
Conditional expression (10) {1- (β2) ² } × (β3) ² = 1.114
Conditional expression (11) FNO × (f1 / f) = 2.534
Conditional expression (12) 2ω = 63.2

FIG. 34 (A) is a diagram of various aberrations of the optical system according to the 17th embodiment at infinity focusing. FIG. 34 (B) is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 17th embodiment. From each aberration diagram, it can be seen that the optical system according to the 17th embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(18th Example)
The eighteenth embodiment will be described with reference to FIGS. 35 to 36 and Table 18. FIG. 35 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the eighteenth embodiment of the present embodiment. In the optical system LS (18) according to the eighteenth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11, a biconvex first positive lens L12, and a meniscus-shaped second negative lens with a concave surface facing the object side, which are arranged in order from the object side. It is composed of L13, a biconvex second positive lens L14, a junction lens composed of a biconvex third positive lens L15 and a biconcave third negative lens L16, and an aperture aperture S. The second negative lens L13 has an aspherical lens surface on the image plane I side. The second positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 includes a biconvex first positive lens L21 arranged in order from the object side, a meniscus-shaped negative lens L22 with a concave surface facing the object side, and a biconvex second positive lens L23. It is composed of a meniscus-shaped third positive lens L24 with a concave surface facing the object side. The second positive lens L23 has aspherical lens surfaces on both sides.

The third lens group G3 consists of a junction lens consisting of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a biconcave first negative lens L32 arranged in order from the object side, and a concave surface facing the object side. It is composed of a second negative lens L33 having a plano-concave shape. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 18 below lists the values of the specifications of the optical system according to the eighteenth embodiment.

(Table 18)
[Overall specifications]
f 36.05
FNO 1.86
ω 31.6
Y 21.70
TL 99.539
BF 13.100
BFa 12.555
[Lens specifications]
Surface number RD nd νd
1 -500.00000 2.000 1.59270 35.3
2 31.30252 8.752
3 77.05411 4.224 1.94594 18.0
4-4995.87340 12.332
5 -34.14226 3.140 1.77377 47.2
6 * -47.59110 0.100
7 * 41.62130 5.898 1.76801 49.2
8 -65.35489 0.294
9 31.07689 6.046 1.59319 67.9
10 -44.14843 1.500 1.69895 30.1
11 22.96400 3.883
12 ∞ D12 (variable) (aperture S)
13 95.03984 2.062 1.49782 82.6
14 -345.94097 2.289
15 -19.00516 1.100 1.64769 33.7
16 -992.59484 1.622
17 * 123.45937 4.722 1.77377 47.2
18 * -28.92599 0.200
19 -129.08817 6.400 1.49782 82.6
20 -21.31763 D20 (variable)
21 -134.41671 5.154 1.94594 18.0
22 -26.15911 1.900 1.80518 25.4
23 1225.10730 3.764
24-34.85007 1.900 1.64769 33.7
25 ∞ 10.500
26 ∞ 1.600 1.51680 64.1
27 ∞ D27 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = 9.02554E-07, A6 = 3.14643E-09, A8 = -1.89905E-12, A10 = 1.77634E-14
Side 7 κ = 1.0000
A4 = -1.81054E-07, A6 = 2.54149E-09, A8 = -7.43973E-12, A10 = 8.48515E-15
Surface 17 κ = 1.0000
A4 = 3.23226E-07, A6 = 4.85057E-08, A8 = 1.37810E-11, A10 = -1.32577E-13
Surface 18 κ = 1.0000
A4 = 2.32157E-05, A6 = 3.57378E-08, A8 = 3.07145E-10, A10 = -6.42283E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 36.05 β = -0.153
D0 ∞ 314.50
D12 4.656 2.000
D20 2.500 5.150
D27 1.000 1.000
[Lens group data]
Focal length
G1 1 58.73
G2 13 33.00
G3 21 -46.85
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=13.870
Conditional expression (2) f2 / (-f3) = 0.704
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=8.514
Conditional expression (4) f / f1 = 0.614
Conditional expression (5) f / f2 = 1.092
Conditional expression (6) f1 / f2 = 1.780
Conditional expression (7) BFa / f = 0.348
Conditional expression (8) fF / fR = 0.765
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) =-0.882
Conditional expression (10) {1- (β2) ² } × (β3) ² = 1.369
Conditional expression (11) FNO × (f1 / f) = 3.025
Conditional expression (12) 2ω = 63.2

FIG. 36A is a diagram of various aberrations of the optical system according to the eighteenth embodiment at infinity focusing. FIG. 36B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the eighteenth embodiment. From each aberration diagram, it can be seen that the optical system according to the eighteenth embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(19th Example)
The nineteenth embodiment will be described with reference to FIGS. 37 to 38 and Table 19. FIG. 37 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 19th embodiment of the present embodiment. In the optical system LS (19) according to the nineteenth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a meniscus-shaped first positive lens L12 with a convex surface facing the object side, and a biconvex second positive lens. It is composed of L13, a junction lens composed of a biconvex third positive lens L14 and a biconcave second negative lens L15, and an aperture stop S. The second positive lens L13 has aspherical lens surfaces on both sides.

The second lens group G2 includes a plano-convex first positive lens L21 having a convex surface facing the image plane I side and a meniscus-shaped negative lens L22 having a concave surface facing the object side, which are arranged in order from the object side. It is composed of a convex second positive lens L23 and a meniscus-shaped third positive lens L24 with a concave surface facing the object side. The second positive lens L23 has aspherical lens surfaces on both sides.

The third lens group G3 is a junction lens composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped first negative lens L32 having a concave surface facing the object side, arranged in order from the object side, and an object. It is composed of a second negative lens L33 having a flat concave shape with a concave surface facing to the side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 19 below lists the values of the specifications of the optical system according to the 19th embodiment. The fifth and sixth surfaces are virtual surfaces.

(Table 19)
[Overall specifications]
f 36.05
FNO 1.87
ω 31.2
Y 21.70
TL 99.566
BF 13.100
BFa 12.555
[Lens specifications]
Surface number RD nd νd
1 -500.00000 2.000 1.59270 35.3
2 26.44740 11.431
3 54.58955 3.977 1.94594 18.0
4 151.93034 2.197
5 ∞ 0.000
6 ∞ 10.067
7 * 40.90811 5.557 1.76801 49.2
8 * -104.02802 0.200
9 29.51647 6.609 1.59319 67.9
10 -42.76988 1.500 1.69895 30.1
11 23.53316 6.210
12 ∞ D12 (variable) (aperture S)
13 ∞ 2.090 1.49782 82.6
14 -74.67300 2.012
15 -18.81061 1.100 1.64769 33.7
16 -248.50402 1.512
17 * 118.78898 4.866 1.77377 47.2
18 * -28.64501 0.200
19 -125.10532 6.400 1.49782 82.6
20 -22.16547 D20 (variable)
21 -66.18341 4.709 1.94594 18.0
22 -24.96921 1.900 1.80518 25.4
23 -199.98195 2.935
24-38.28094 1.900 1.64769 33.7
25 ∞ 10.500
26 ∞ 1.600 1.51680 64.1
27 ∞ D27 (variable)
[Aspherical data]
Side 7 κ = 1.0000
A4 = 3.16584E-07, A6 = 2.60390E-09, A8 = -1.78975E-11, A10 = 5.41316E-14
Side 8 κ = 1.0000
A4 = 4.34400E-08, A6 = -4.51994E-10, A8 = -7.80080E-12, A10 = 3.78367E-14
Surface 17 κ = 1.0000
A4 = -3.61366E-06, A6 = 5.25325E-08, A8 = -5.32628E-12, A10 = 1.17020E-14
Surface 18 κ = 1.0000
A4 = 2.00858E-05, A6 = 3.18374E-08, A8 = 2.71615E-10, A10 = -4.03272E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 36.05 β = -0.1049
D0 ∞ 314.50
D12 4.594 2.000
D20 2.500 5.088
D27 1.000 1.000
[Lens group data]
Focal length
G1 1 53.15
G2 13 32.25
G3 21 -45.20
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=13.870
Conditional expression (2) f2 / (-f3) = 0.714
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=9.407
Conditional expression (4) f / f1 = 0.678
Conditional expression (5) f / f2 = 1.118
Conditional expression (6) f1 / f2 = 1.648
Conditional expression (7) BFa / f = 0.348
Conditional expression (8) fF / fR = 0.626
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) =-0.900
Conditional expression (10) {1- (β2) ² } × (β3) ² = 1.388
Conditional expression (11) FNO × (f1 / f) = 2.751
Conditional expression (12) 2ω = 62.4

FIG. 38 (A) is a diagram of various aberrations of the optical system according to the 19th embodiment at infinity focusing. FIG. 38B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the nineteenth embodiment. From each aberration diagram, it can be seen that the optical system according to the 19th embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(20th Example)
A twentieth embodiment will be described with reference to FIGS. 39 to 40 and Table 20. FIG. 39 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 20th embodiment of the present embodiment. In the optical system LS (20) according to the twentieth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a meniscus-shaped first negative lens L11 having a convex surface facing the object side, a meniscus-shaped second negative lens L12 having a convex surface facing the object side, and a meniscus-shaped second negative lens L12 arranged in order from the object side. A junction lens consisting of a meniscus-shaped first positive lens L13 with a convex surface, a meniscus-shaped third negative lens L14 with a concave surface facing the object side, a biconvex second positive lens L15, and a biconvex shape. It is composed of a junction lens composed of a third positive lens L16 and a biconcave fourth negative lens L17, and an aperture aperture S. The second positive lens L15 has an aspherical lens surface on the object side.

The second lens group G2 includes a biconcave negative lens L21 arranged in order from the object side, a meniscus-shaped first positive lens L22 with a concave surface facing the object side, and a biconvex second positive lens L23. It is composed of a meniscus-shaped third positive lens L24 with a concave surface facing the object side. The first positive lens L22 has an aspherical lens surface on the object side.

The third lens group G3 is composed of a meniscus-shaped first negative lens L31 having a convex surface facing the object side and a meniscus-shaped second negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. Will be done. The second negative lens L32 has an aspherical lens surface on the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 20 below lists the values of the specifications of the optical system according to the 20th embodiment.

(Table 20)
[Overall specifications]
f 36.41
FNO 1.45
ω 30.7
Y 21.70
TL 120.000
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 117.52540 2.000 1.71736 29.6
2 26.99520 8.652
3 42.97983 2.500 1.48749 70.3
4 34.72137 5.000 1.94595 18.0
5 45.17490 9.389
6 -52.71945 6.000 1.60300 65.4
7 -131.66451 0.200
8 * 55.12835 9.000 1.77250 49.6
9 -66.63993 0.200
10 57.67591 13.000 1.59319 67.9
11 -28.99052 1.500 1.67270 32.2
12 230.60272 5.399
13 ∞ D13 (variable) (aperture S)
14 -30.96994 1.000 1.67270 32.2
15 1151.90580 2.000
16 * -406.76312 4.000 1.77377 47.2
17 -45.06075 0.881
18 140.10078 6.000 1.59319 67.9
19 -58.07296 0.500
20 -100.00000 7.000 1.59319 67.9
21 -30.10496 D21 (variable)
22 74.17179 3.000 1.94595 18.0
23 67.04188 7.824
24 * -26.97932 1.500 1.64769 33.7
25 -290.34268 7.000
26 ∞ 1.600 1.51680 63.9
27 ∞ D27 (variable)
[Aspherical data]
Side 8 κ = 1.0000
A4 = -6.93107E-07, A6 = -4.54051E-10, A8 = 1.72053E-12, A10 = -1.39325E-15
16th surface κ = 1.0000
A4 = -1.46752E-05, A6 = -1.19814E-08, A8 = 3.20679E-11, A10 = -2.43972E-13
Side 24 κ = 1.0000
A4 = 1.09875E-05, A6 = 2.56103E-09, A8 = -8.64670E-12, A10 = -3.14024E-14
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 36.41 β = -0.1095
D0 ∞ 290.00
D13 13.354 9.399
D21 0.500 4.455
D27 1.000 1.000
[Lens group data]
Focal length
G1 1 48.51
G2 14 38.61
G3 22 -44.33
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=-3.228
Conditional expression (2) f2 / (-f3) = 0.871
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=-2.423
Conditional expression (4) f / f1 = 0.751
Conditional expression (5) f / f2 = 0.943
Conditional expression (6) f1 / f2 = 1.256
Conditional expression (7) BFa / f = 0.249
Conditional expression (8) fF / fR = 0.358
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) =-1.596
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.914
Conditional expression (11) FNO × (f1 / f) = 1.936
Conditional expression (12) 2ω = 61.4

FIG. 40A is a diagram of various aberrations of the optical system according to the twentieth embodiment at infinity focusing. FIG. 40B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the twentieth embodiment. From each aberration diagram, it can be seen that the optical system according to the twentieth embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(21st Example)
The 21st Example will be described with reference to FIGS. 41 to 42 and Table 21. FIG. 41 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 21st embodiment of the present embodiment. In the optical system LS (21) according to the 21st embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a meniscus-shaped second negative lens L12 with a convex surface facing the object side, and a meniscus shape with a convex surface facing the object side. A junction lens composed of the first positive lens L13, a biconcave third negative lens L14, a biconvex second positive lens L15, and a meniscus-shaped third positive lens L16 with a convex surface facing the object side. It is composed of a junction lens consisting of a meniscus-shaped fourth negative lens L17 having a convex surface facing the object side and a meniscus-shaped fourth positive lens L18 having a convex surface facing the object side, and an aperture aperture S. The second positive lens L15 has aspherical lens surfaces on both sides.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a meniscus-shaped first positive lens L22 having a concave surface facing the object side, and a biconvex lens arranged in order from the object side. It is composed of a second positive lens L23 and a meniscus-shaped third positive lens L24 with a concave surface facing the object side. The first positive lens L22 has an aspherical lens surface on the object side.

The third lens group G3 consists of a meniscus-shaped first negative lens L31 having a convex surface facing the object side and a plano-concave second negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. It is composed. The second negative lens L32 has an aspherical lens surface on the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 21 below lists the values of the specifications of the optical system according to the 21st embodiment.

(Table 21)
[Overall specifications]
f 36.00
FNO 1.42
ω 31.2
Y 21.70
TL 125.000
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 -2103.91320 2.000 1.67884 31.5
2 35.70457 7.893
3 323.10172 2.500 1.49086 69.1
4 67.22138 5.500 1.94595 18.0
5 787.71792 7.911
6 -39.04627 2.000 1.69166 30.1
7 213.89102 0.100
8 * 137.58827 12.000 1.85135 40.1
9 * -47.56574 0.200
10 39.72534 7.000 1.83481 42.7
11 181.94050 2.130
12 117.83429 1.500 1.75520 27.6
13 23.80746 9.000 1.59319 67.9
14 183.46004 3.500
15 ∞ D15 (variable) (aperture S)
16 -34.21404 1.000 1.67270 32.2
17 -122.91319 2.000
18 * -86.16442 3.500 1.77377 47.2
19 -48.56224 2.416
20 1800.15400 5.500 1.59319 67.9
21 -42.45537 0.500
22 -100.00000 6.500 1.59319 67.9
23 -30.05033 D23 (variable)
24 39.40559 3.000 1.94595 18.0
25 34.37457 9.136
26 * -44.57372 1.500 1.64769 33.7
27 ∞ 7.000
28 ∞ 1.600 1.51680 63.9
29 ∞ D29 (variable)
[Aspherical data]
Side 8 κ = 1.0000
A4 = 3.90875E-07, A6 = 5.99792E-10, A8 = -1.78965E-12, A10 = 1.89102E-15
Side 9 κ = 1.0000
A4 = 5.52339E-07, A6 = 1.13820E-09, A8 = -1.99242E-12, A10 = 2.23323E-15
Surface 18 κ = 1.0000
A4 = -1.62045E-05, A6 = -1.75085E-08, A8 = 3.19334E-11, A10 = -3.05989E-13
Side 26 κ = 1.0000
A4 = -1.48857E-06, A6 = -3.93600E-09, A8 = 2.22864E-12, A10 = -4.82017E-14
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 36.00 β = -0.1086
D0 ∞ 290.00
D15 16.614 12.490
D23 0.500 4.624
D29 1.000 1.000
[Lens group data]
Focal length
G1 1 52.88
G2 16 39.96
G3 24 -59.46
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=58.442
Conditional expression (2) f2 / (-f3) = 0.672
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=39.787
Conditional expression (4) f / f1 = 0.681
Conditional expression (5) f / f2 = 0.901
Conditional expression (6) f1 / f2 = 1.323
Conditional expression (7) BFa / f = 0.252
Conditional expression (8) fF / fR = 0.622
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = -0.967
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.867
Conditional expression (11) FNO × (f1 / f) = 2.080
Conditional expression (12) 2ω = 62.4

FIG. 42 (A) is an aberration diagram of the optical system according to the 21st embodiment at infinity focusing. FIG. 42B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 21st embodiment. From each aberration diagram, it can be seen that the optical system according to the 21st embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(22nd Example)
The 22nd embodiment will be described with reference to FIGS. 43 to 44 and Table 22. FIG. 43 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 22nd embodiment of the present embodiment. In the optical system LS (22) according to the 22nd embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a junction lens consisting of a biconcave first negative lens L11 arranged in order from the object side and a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and a concave surface on the object side. A junction lens consisting of a meniscus-shaped second positive lens L13, a biconvex third positive lens L14, a biconvex fourth positive lens L15, and a biconcave second negative lens L16, and an aperture aperture. It is composed of S and. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 is composed of a meniscus-shaped negative lens L21 having a concave surface facing the object side and a biconvex positive lens L22 arranged in order from the object side. The positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 22 below lists the values of the specifications of the optical system according to the 22nd embodiment. The twelfth surface is a virtual surface.

(Table 22)
[Overall specifications]
f 51.50
FNO 1.85
ω 22.9
Y 21.70
TL 89.489
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 -47.35217 2.500 1.67270 32.2
2 94.47970 3.500 1.94595 18.0
3 340.13397 3.236
4-287.21979 5.000 1.72916 54.6
5 -56.34930 0.100
6 * 35.86692 6.000 1.80400 46.6
7 -2318.43510 0.200
8 45.67330 7.000 1.59319 67.9
9-80.81919 1.500 1.64769 33.7
10 23.62983 4.933
11 ∞ D11 (variable) (aperture S)
12 ∞ 3.000
13 -19.53832 1.100 1.75520 27.6
14 -43.18210 1.500
15 * 190.26772 7.000 1.75501 51.2
16 * -24.77289 D16 (variable)
17 -104.87147 2.500 1.94595 18.0
18 -78.84438 14.090
19 -38.56539 1.900 1.64769 33.7
20 -200.67448 7.000
21 ∞ 1.600 1.51680 64.1
22 ∞ D22 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -1.58615E-06, A6 = -8.54477E-10, A8 = -4.09102E-13, A10 = 5.85218E-16
Surface 15 κ = 1.0000
A4 = 4.66858E-07, A6 = -2.10629E-08, A8 = 1.67228E-10, A10 = -2.90665E-13
16th surface κ = 1.0000
A4 = 8.47233E-06, A6 = 2.18602E-10, A8 = 2.67616E-11, A10 = 1.23427E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.50 β = -0.1588
D0 ∞ 305.05
D11 12.719 2.695
D16 2.111 12.136
D22 1.000 1.000
[Lens group data]
Focal length
G1 1 75.53
G2 12 56.74
G3 17 -100.37
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.919
Conditional expression (2) f2 / (-f3) = 0.565
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.627
Conditional expression (4) f / f1 = 0.682
Conditional expression (5) f / f2 = 0.908
Conditional expression (6) f1 / f2 = 1.331
Conditional expression (7) BFa / f = 0.176
Conditional expression (8) fF / fR = 0.762
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.756
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.687
Conditional expression (11) FNO × (f1 / f) = 2.716
Conditional expression (12) 2ω = 45.8

FIG. 44A is a diagram of various aberrations of the optical system according to the 22nd embodiment at infinity focusing. FIG. 44B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 22nd embodiment. From each aberration diagram, it can be seen that the optical system according to the 22nd embodiment has various aberrations corrected well and has excellent imaging performance.

(23rd Example)
The 23rd embodiment will be described with reference to FIGS. 45 to 46 and Table 23. FIG. 45 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 23rd embodiment of the present embodiment. In the optical system LS (23) according to the 23rd embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a junction lens consisting of a biconcave first negative lens L11 arranged in order from the object side and a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and a concave surface on the object side. A meniscus-shaped second positive lens L13, a biconvex third positive lens L14, a meniscus-shaped fourth positive lens L15 with a convex surface facing the object side, and a meniscus-shaped second lens L15 with a convex surface facing the object side. It is composed of a junction lens made of 2 negative lenses L16 and an aperture aperture S. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped first positive lens L21 having a concave surface facing the object side, a meniscus-shaped negative lens L22 having a concave surface facing the object side, and a biconvex lens arranged in order from the object side. It is composed of a second positive lens L23. The second positive lens L23 has aspherical lens surfaces on both sides.

The third lens group G3 is composed of a meniscus-shaped first negative lens L31 having a concave surface facing the object side and a meniscus-shaped second negative lens L32 having a concave surface facing the object side, arranged in order from the object side. Will be done. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 23 below lists the values of the specifications of the optical system according to the 23rd embodiment. The 20th surface is a virtual surface.

(Table 23)
[Overall specifications]
f 51.08
FNO 1.86
ω 23.0
Y 21.70
TL 90.000
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 -52.31571 2.500 1.67270 32.2
2 167.47695 3.500 1.94595 18.0
3 223.17328 4.121
4-82.07390 4.000 1.72916 54.6
5 -45.42951 0.100
6 * 38.12626 6.000 1.80400 46.6
7 -3600.28350 1.699
8 27.04928 5.000 1.59319 67.9
9 41.33566 1.500 1.64769 33.7
10 20.68760 5.718
11 ∞ D11 (variable) (aperture S)
12 -22.93194 2.500 1.49700 81.6
13 -17.98615 0.500
14 -17.23374 1.100 1.67270 32.2
15 -49.04852 1.500
16 * 279.75740 6.000 1.75501 51.2
17 * -26.00590 D17 (variable)
18 -221.46549 2.500 1.94595 18.0
19 -230.39803 0.000
20 ∞ 10.724
21 -38.50025 1.900 1.64769 33.7
22 -110.45885 7.000
23 ∞ 1.600 1.51680 63.9
24 ∞ D24 (variable)
[Aspherical data]
Side 6 κ = 1.0000
A4 = -1.19548E-06, A6 = -9.73538E-10, A8 = 3.03150E-12, A10 = -5.31839E-15
16th surface κ = 1.0000
A4 = -1.22099E-06, A6 = -9.91302E-09, A8 = 8.68866E-11, A10 = -1.19726E-13
Surface 17 κ = 1.0000
A4 = 5.66916E-06, A6 = 2.72450E-09, A8 = -8.54602E-12, A10 = 1.63651E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.08 β = -0.1171
D0 ∞ 413.36
D11 12.216 4.956
D17 7.322 14.582
D24 1.000 1.000
[Lens group data]
Focal length
G1 1 68.94
G2 12 58.61
G3 18 -90.38
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=1.024
Conditional expression (2) f2 / (-f3) = 0.648
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.759
Conditional expression (4) f / f1 = 0.741
Conditional expression (5) f / f2 = 0.872
Conditional expression (6) f1 / f2 = 1.176
Conditional expression (7) BFa / f = 0.177
Conditional expression (8) fF / fR = 0.542
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.620
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.721
Conditional expression (11) FNO × (f1 / f) = 2.508
Conditional expression (12) 2ω = 46.0

FIG. 46 (A) is a diagram of various aberrations of the optical system according to the 23rd embodiment at infinity focusing. FIG. 46B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 23rd embodiment. From each aberration diagram, it can be seen that the optical system according to the 23rd embodiment has various aberrations corrected well and has excellent imaging performance.

(24th Example)
The 24th embodiment will be described with reference to FIGS. 47 to 48 and Table 24. FIG. 47 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 24th embodiment of the present embodiment. In the optical system LS (24) according to the 24th embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a meniscus-shaped first positive lens L12 with a concave surface facing the object side, and a meniscus with a convex surface facing the object side. A junction lens consisting of a second positive lens L13 having a shape, a meniscus-shaped third positive lens L14 having a convex surface facing the object side, and a meniscus-shaped second negative lens L15 having a convex surface facing the object side, and an aperture diaphragm S. , Consists of. The second positive lens L13 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped first positive lens L21 having a concave surface facing the object side, a meniscus-shaped negative lens L22 having a concave surface facing the object side, and a biconvex lens arranged in order from the object side. It is composed of a second positive lens L23. The second positive lens L23 has aspherical lens surfaces on both sides.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a convex surface facing the object side and a meniscus-shaped negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 24 below lists the values of the specifications of the optical system according to the 24th embodiment.

(Table 24)
[Overall specifications]
f 51.50
FNO 1.85
ω 22.9
Y 21.70
TL 82.941
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 -47.29734 2.000 1.67270 32.2
2 2331.06620 3.670
3 -71.21945 4.000 1.72916 54.6
4-42.49265 0.100
5 * 34.70954 6.000 1.80400 46.6
6 6260.90290 0.947
7 27.53256 5.000 1.59319 67.9
8 40.45186 1.500 1.64769 33.7
9 19.48030 5.755
10 ∞ D10 (variable) (aperture S)
11 -21.95759 2.500 1.49700 81.6
12 -17.97990 0.500
13 -17.33726 1.100 1.67270 32.2
14 -65.42718 0.387
15 * 210.98797 6.000 1.75501 51.2
16 * -24.41048 D16 (variable)
17 79.42309 2.500 1.94595 18.0
18 102.63179 8.767
19 -46.77211 1.900 1.84666 23.8
20 -182.21442 7.000
21 ∞ 1.600 1.51680 63.9
22 ∞ D22 (variable)
[Aspherical data]
Side 5 κ = 1.0000
A4 = -1.79931E-06, A6 = -1.35228E-09, A8 = 1.30531E-12, A10 = -3.27717E-15
Surface 15 κ = 1.0000
A4 = -1.14256E-06, A6 = -1.30370E-08, A8 = 1.13854E-10, A10 = -1.79669E-13
16th surface κ = 1.0000
A4 = 6.47116E-06, A6 = 6.32503E-09, A8 = -2.44521E-11, A10 = 2.46075E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.50 β = -0.1181
D0 ∞ 413.36
D10 14.069 5.072
D16 6.646 15.643
D22 1.000 1.000
[Lens group data]
Focal length
G1 1 68.06
G2 11 64.03
G3 17 -99.89
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=0.918
Conditional expression (2) f2 / (-f3) = 0.641
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.695
Conditional expression (4) f / f1 = 0.757
Conditional expression (5) f / f2 = 0.804
Conditional expression (6) f1 / f2 = 1.063
Conditional expression (7) BFa / f = 0.176
Conditional expression (8) fF / fR = 0.514
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.960
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.563
Conditional expression (11) FNO × (f1 / f) = 2.445
Conditional expression (12) 2ω = 45.8

FIG. 48A is a diagram of various aberrations of the optical system according to the 24th embodiment at infinity focusing. FIG. 48B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 24th embodiment. From each aberration diagram, it can be seen that the optical system according to the 24th embodiment has various aberrations corrected well and has excellent imaging performance.

(25th Example)
The 25th embodiment will be described with reference to FIGS. 49 to 50 and Table 25. FIG. 49 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 25th embodiment of the present embodiment. In the optical system LS (25) according to the 25th embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11 arranged in order from the object side, a meniscus-shaped first positive lens L12 with a concave surface facing the object side, and a meniscus with a convex surface facing the object side. It is composed of a second positive lens L13 having a shape, a second negative lens L14 having a meniscus shape with a convex surface facing the object side, and an aperture stop S. The second positive lens L13 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped first positive lens L21 having a concave surface facing the object side, a meniscus-shaped negative lens L22 having a concave surface facing the object side, and a biconvex lens arranged in order from the object side. It is composed of a second positive lens L23. The second positive lens L23 has aspherical lens surfaces on both sides.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a convex surface facing the object side and a plano-concave-shaped negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 25 below lists the values of the specifications of the optical system according to the 25th embodiment.

(Table 25)
[Overall specifications]
f 50.81
FNO 1.85
ω 23.1
Y 21.70
TL 80.000
BF 9.600
BFa 9.055
[Lens specifications]
Surface number RD nd νd
1 -48.70279 2.000 1.67270 32.2
2 958.65257 2.567
3 -87.18050 3.500 1.72916 54.6
4-45.33683 0.100
5 * 28.25675 6.500 1.77250 49.6
6 735.50092 0.365
7 28.50942 2.465 1.67270 32.2
8 19.47871 6.238
9 ∞ D9 (variable) (aperture S)
10 -21.86257 2.000 1.49700 81.6
11 -18.15776 0.500
12 -17.46272 1.100 1.67270 32.2
13 -78.54612 0.200
14 * 259.64263 6.500 1.75501 51.2
15 * -23.47358 D15 (variable)
16 45.54867 2.500 1.94595 18.0
17 56.06952 6.419
18 -49.21248 1.900 1.84666 23.8
19 ∞ 7.000
20 ∞ 1.600 1.51680 63.9
21 ∞ D21 (variable)
[Aspherical data]
Side 5 κ = 1.0000
A4 = -3.06009E-06, A6 = -3.83923E-09, A8 = 3.08021E-12, A10 = -1.31813E-14
14th surface κ = 1.0000
A4 = -2.38445E-06, A6 = -7.07397E-10, A8 = 4.93804E-11, A10 = -6.99716E-14
Surface 15 κ = 1.0000
A4 = 6.07250E-06, A6 = 1.41158E-08, A8 = -5.03385E-11, A10 = 2.68237E-13
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 50.81 β = -0.1180
D0 ∞ 413.36
D9 14.286 5.350
D15 11.261 20.197
D21 1.000 1.000
[Lens group data]
Focal length
G1 1 67.37
G2 10 68.93
G3 16 -83.91
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.958
Conditional expression (2) f2 / (-f3) = 0.821
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.723
Conditional expression (4) f / f1 = 0.754
Conditional expression (5) f / f2 = 0.737
Conditional expression (6) f1 / f2 = 0.977
Conditional expression (7) BFa / f = 0.178
Conditional expression (8) fF / fR = 0.349
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.903
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.567
Conditional expression (11) FNO × (f1 / f) = 2.456
Conditional expression (12) 2ω = 46.2

FIG. 50A is an aberration diagram of the optical system according to the 25th embodiment at infinity focusing. FIG. 50B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 25th embodiment. From each aberration diagram, it can be seen that the optical system according to the 25th embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(26th Example)
The 26th embodiment will be described with reference to FIGS. 51 to 52 and Table 26. FIG. 51 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 26th embodiment of the present embodiment. In the optical system LS (26) according to the 26th embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. Further, the second lens group G2 is composed of a first subgroup G2A having a negative refractive power and a second subgroup G2B having a positive refractive power arranged in order from the object side. When focusing from an infinity object to a short-distance (finite distance) object, the first subgroup G2A and the second subgroup G2B of the second lens group G2 move along the optical axis with different amounts of movement on the object side. The first lens group G1 and the third lens group G3 are fixed.

The first lens group G1 is a junction lens composed of a biconcave first negative lens L11 arranged in order from the object side, a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and a biconcave first lens group G1. A junction consisting of a 2-negative lens L13, a biconvex second positive lens L14, a biconvex third positive lens L15, a biconvex fourth positive lens L16, and a biconcave third negative lens L17. It is composed of a lens and an aperture aperture S. The third positive lens L15 has aspherical lens surfaces on both sides.

The first subgroup G2A of the second lens group G2 is composed of a meniscus-shaped negative lens L21 with a concave surface facing the object side. The second subgroup G2B of the second lens group G2 is composed of a biconvex first positive lens L22 arranged in order from the object side and a meniscus-shaped second regular lens L23 with a concave surface facing the object side. Will be done. The first positive lens L22 has aspherical lens surfaces on both sides.

The third lens group G3 consists of a junction lens consisting of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a biconcave first negative lens L32 arranged in order from the object side, and a concave surface facing the object side. It is composed of a second negative lens L33 having a plano-concave shape. The second negative lens L33 has an aspherical lens surface on the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 26 below lists the values of the specifications of the optical system according to the 26th embodiment.

(Table 26)
[Overall specifications]
f 51.60
FNO 1.44
ω 22.7
Y 21.70
TL 113.685
BF 13.100
BFa 12.555
[Lens specifications]
Surface number RD nd νd
1 -171.72474 2.000 1.62588 35.7
2 35.44631 5.392 1.94594 18.0
3 74.33039 6.970
4-53.50931 3.610 1.75520 27.6
5 91.70821 0.200
6 74.06522 7.512 1.90265 35.7
7 -104.97613 0.100
8 * 56.97323 7.742 1.85135 40.1
9 * -173.82221 0.200
10 38.89486 12.894 1.59319 67.9
11 -34.37837 1.500 1.74077 27.7
12 37.65571 4.597
13 ∞ D13 (variable) (aperture S)
14 -22.59808 1.100 1.64769 33.7
15 -145.29857 D15 (variable)
16 * 85.83165 6.797 1.77377 47.2
17 * -32.92442 1.000
18 -62.36306 6.400 1.49782 82.6
19 -26.53221 D19 (variable)
20 -15532.87600 5.451 1.94594 18.0
21 -42.26207 4.169 1.75520 27.6
22 1509.21760 3.688
23 * -47.39475 1.900 1.88202 37.2
24 ∞ 10.500
25 ∞ 1.600 1.51680 64.1
26 ∞ D26 (variable)
[Aspherical data]
Side 8 κ = 1.0000
A4 = 1.10048E-06, A6 = 1.15261E-10, A8 = 4.34134E-12, A10 = -9.02791E-16
Side 9 κ = 1.0000
A4 = 2.53480E-06, A6 = -1.36378E-09, A8 = 6.90741E-12, A10 = -6.444423E-15
16th surface κ = 1.0000
A4 = -2.75452E-06, A6 = 1.71160E-08, A8 = -1.40699E-11, A10 = 1.45752E-14
Surface 17 κ = 1.0000
A4 = 1.20601E-05, A6 = 1.19411E-08, A8 = 3.74420E-11, A10 = -3.48136E-14
Side 23 κ = 1.0000
A4 = 1.37602E-06, A6 = -3.97295E-09, A8 = 7.39073E-12, A10 = -9.76367E-15
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 51.60 β = -0.1471
D0 ∞ 314.50
D13 13.416 6.329
D15 1.447 1.481
D19 2.500 9.547
D26 1.000 1.000
[Lens group data]
Focal length
G1 1 81.01
G2 14 42.29
(G2A 14 -41.46)
(G2B 16 25.11)
G4 20 -70.49
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=0.922
Conditional expression (2) f2 / (-f3) = 0.614
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.588
Conditional expression (4) f / f1 = 0.637
Conditional expression (5) f / f2 = 1.192
Conditional expression (6) f1 / f2 = 1.871
Conditional expression (7) BFa / f = 0.243
Conditional expression (8) fF / fR = 0.976
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.219
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.957
Conditional expression (11) FNO × (f1 / f) = 2.263
Conditional expression (12) 2ω = 45.4

FIG. 52 (A) is a diagram of various aberrations of the optical system according to the 26th embodiment at infinity focusing. FIG. 52 (B) is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 26th embodiment. From each aberration diagram, it can be seen that the optical system according to the 26th embodiment has various aberrations corrected well and has excellent imaging performance.

(27th Example)
The 27th embodiment will be described with reference to FIGS. 53 to 54 and Table 27. FIG. 53 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 27th embodiment of the present embodiment. In the optical system LS (27) according to the 27th embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a meniscus-shaped first negative lens L11 having a concave surface facing the object side, a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and biconvex lenses arranged in order from the object side. A junction lens consisting of a second positive lens L13 having a shape, a third positive lens L14 having a meniscus shape with a convex surface facing the object side, a fourth positive lens L15 having a biconvex shape, and a second negative lens L16 having a biconcave shape. , And an opening aperture S.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a meniscus-shaped lens L22 having a concave surface facing the object side, arranged in order from the object side. It is composed of a second positive lens L23. The lens surface of the first positive lens L22 on the image plane I side is an aspherical surface.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a meniscus-shaped negative lens L32 having a concave surface facing the object side, which are arranged in order from the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 27 below lists the values of the specifications of the optical system according to the 27th embodiment.

(Table 27)
[Overall specifications]
f 85.00
FNO 1.86
ω 14.2
Y 21.70
TL 115.209
BF 21.685
BFa 21.004
[Lens specifications]
Surface number RD nd νd
1 -64.83088 2.500 1.67270 32.2
2-188.98518 0.300
3 153.82997 4.500 1.94595 18.0
4 508.32386 0.300
5 420.81318 6.000 1.72916 54.6
6 -110.04917 0.100
7 48.16622 7.000 1.72916 54.6
8 79.79724 0.200
9 40.00000 10.958 1.59282 68.7
10 -125.87904 2.500 1.67270 32.2
11 25.51317 7.152
12 ∞ D12 (variable) (aperture S)
13 -30.69513 1.500 1.64769 33.7
14 -1583.64670 1.500
15 84.28063 5.000 1.77377 47.2
16 * -60.30181 1.500
17 -115.77812 4.500 1.49700 81.6
18 -35.95414 D18 (variable)
19 -79.69114 4.000 1.94595 18.0
20 -48.89207 6.639
21 -37.38750 2.000 1.64769 33.7
22 -237.55752 18.685
23 ∞ 2.000 1.51680 64.1
24 ∞ D24 (variable)
[Aspherical data]
16th surface κ = 1.0000
A4 = 4.07807E-06, A6 = 3.17226E-09, A8 = -8.77566E-12, A10 = 1.60757E-14
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 85.00 β = -0.1252
D0 ∞ 661.16
D12 17.304 5.692
D18 8.071 19.684
D24 1.000 1.000
[Lens group data]
Focal length
G1 1 129.04
G2 13 75.91
G3 19 -161.19
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.763
Conditional expression (2) f2 / (-f3) = 0.471
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.502
Conditional expression (4) f / f1 = 0.659
Conditional expression (5) f / f2 = 1.120
Conditional expression (6) f1 / f2 = 1.700
Conditional expression (7) BFa / f = 0.247
Conditional expression (8) fF / fR = 1.054
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 2.044
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.804
Conditional expression (11) FNO × (f1 / f) = 2.825
Conditional expression (12) 2ω = 28.4

FIG. 54 (A) is a diagram of various aberrations of the optical system according to the 27th embodiment at infinity focusing. FIG. 54B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 27th embodiment. From each aberration diagram, it can be seen that the optical system according to the 27th embodiment has various aberrations corrected well and has excellent imaging performance.

(28th Example)
The 28th embodiment will be described with reference to FIGS. 55 to 56 and Table 28. FIG. 55 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 28th embodiment of the present embodiment. In the optical system LS (28) according to the 28th embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a meniscus-shaped first negative lens L11 having a concave surface facing the object side, a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and biconvex lenses arranged in order from the object side. A junction lens consisting of a second positive lens L13 having a shape, a third positive lens L14 having a meniscus shape with a convex surface facing the object side, a fourth positive lens L15 having a biconvex shape, and a second negative lens L16 having a biconcave shape. , And an opening aperture S.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a meniscus-shaped lens L22 having a concave surface facing the object side, arranged in order from the object side. It is composed of a second positive lens L23. The lens surface of the first positive lens L22 on the image plane I side is an aspherical surface.

The third lens group G3 is composed of a biconvex positive lens L31 and a biconcave negative lens L32 arranged in order from the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 28 below lists the values of the specifications of the optical system according to the 28th embodiment.

(Table 28)
[Overall specifications]
f 85.00
FNO 1.83
ω 14.2
Y 21.70
TL 115.187
BF 19.721
BFa 19.039
[Lens specifications]
Surface number RD nd νd
1 -72.98373 2.500 1.67270 32.2
2 -170.26652 0.300
3 117.64422 4.500 1.94595 18.0
4 186.71439 0.436
5 189.13820 6.000 1.72916 54.6
6 -151.29429 0.100
7 50.47764 7.000 1.72916 54.6
8 72.74698 0.200
9 40.25986 11.919 1.59282 68.7
10 -195.06452 2.500 1.67270 32.2
11 26.55143 6.702
12 ∞ D12 (variable) (aperture S)
13 -29.45199 1.500 1.64769 33.7
14 -432.91007 1.500
15 95.51607 5.000 1.77377 47.2
16 * -57.35798 1.500
17 -90.11025 4.500 1.49700 81.6
18 -33.31937 D18 (variable)
19 17922.25800 4.000 1.94595 18.0
20 -128.51263 6.878
21 -63.86657 2.000 1.64769 33.7
22 153.63984 16.721
23 ∞ 2.000 1.51680 64.1
24 ∞ D24 (variable)
[Aspherical data]
16th surface κ = 1.0000
A4 = 4.53083E-06, A6 = 3.16311E-09, A8 = -8.83761E-12, A10 = 1.81194E-14
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 85.00 β = -0.1247
D0 ∞ 661.16
D12 18.306 5.696
D18 8.127 20.736
D24 1.000 1.000
[Lens group data]
Focal length
G1 1 131.54
G2 13 77.05
G3 19 -160.72
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.859
Conditional expression (2) f2 / (-f3) = 0.479
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.555
Conditional expression (4) f / f1 = 0.646
Conditional expression (5) f / f2 = 1.103
Conditional expression (6) f1 / f2 = 1.707
Conditional expression (7) BFa / f = 0.224
Conditional expression (8) fF / fR = 1.101
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 2.500
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.727
Conditional expression (11) FNO × (f1 / f) = 2.839
Conditional expression (12) 2ω = 28.4

FIG. 56A is an aberration diagram of the optical system according to the 28th embodiment at infinity focusing. FIG. 56B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 28th embodiment. From each aberration diagram, it can be seen that the optical system according to the 28th embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(29th Example)
The 29th embodiment will be described with reference to FIGS. 57 to 58 and Table 29. FIG. 57 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 29th embodiment of the present embodiment. In the optical system LS (29) according to the 29th embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a meniscus-shaped first negative lens L11 having a concave surface facing the object side, a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and biconvex lenses arranged in order from the object side. A junction lens consisting of a second positive lens L13 having a shape, a third positive lens L14 having a meniscus shape with a convex surface facing the object side, a fourth positive lens L15 having a biconvex shape, and a second negative lens L16 having a biconcave shape. , And an opening aperture S.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a meniscus-shaped lens L22 having a concave surface facing the object side, arranged in order from the object side. It is composed of a second positive lens L23. The lens surface of the first positive lens L22 on the image plane I side is an aspherical surface.

The third lens group G3 is composed of a biconvex positive lens L31 and a biconcave negative lens L32 arranged in order from the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 29 below lists the values of the specifications of the optical system according to the 29th embodiment.

(Table 29)
[Overall specifications]
f 85.00
FNO 1.85
ω 14.2
Y 21.70
TL 115.297
BF 15.435
BFa 14.754
[Lens specifications]
Surface number RD nd νd
1 -75.54007 2.500 1.67270 32.2
2 -147.54550 0.300
3 88.89576 4.500 1.94595 18.0
4 118.01688 0.648
5 127.59306 6.000 1.80400 46.6
6 -246.54425 0.100
7 47.61283 6.000 1.59282 68.6
8 67.76235 0.200
9 40.00000 10.476 1.59282 68.7
10 -185.31557 2.500 1.67270 32.2
11 26.38137 6.867
12 ∞ D12 (variable) (aperture S)
13 -28.70718 1.500 1.64769 33.7
14 -336.87946 1.500
15 97.83173 5.000 1.77377 47.2
16 * -54.59764 1.500
17 -87.32308 4.500 1.49700 81.6
18 -32.94421 D18 (variable)
19 3326.05740 4.000 1.94595 18.0
20 -105.25167 4.274
21 -57.51449 2.000 1.64769 33.7
22 111.93382 12.435
23 ∞ 2.000 1.51680 64.1
24 ∞ D24 (variable)
[Aspherical data]
16th surface κ = 1.0000
A4 = 4.61985E-06, A6 = 4.41333E-09, A8 = -1.50995E-11, A10 = 2.98769E-14
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 85.00 β = -0.1232
D0 ∞ 661.16
D12 21.713 9.146
D18 13.783 26.349
D24 1.000 1.000
[Lens group data]
Focal length
G1 1 131.08
G2 13 74.60
G3 19 -140.71
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.889
Conditional expression (2) f2 / (-f3) = 0.530
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.576
Conditional expression (4) f / f1 = 0.648
Conditional expression (5) f / f2 = 1.139
Conditional expression (6) f1 / f2 = 1.757
Conditional expression (7) BFa / f = 0.174
Conditional expression (8) fF / fR = 1.081
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 3.098
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.717
Conditional expression (11) FNO × (f1 / f) = 2.850
Conditional expression (12) 2ω = 28.4

FIG. 58 (A) is an aberration diagram of the optical system according to the 29th embodiment at infinity focusing. FIG. 58 (B) is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 29th embodiment. From each aberration diagram, it can be seen that the optical system according to the 29th embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(30th Example)
The thirtieth embodiment will be described with reference to FIGS. 59 to 60 and Table 30. FIG. 59 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the thirtieth embodiment of the present embodiment. In the optical system LS (30) according to the thirtieth embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a meniscus-shaped first negative lens L11 having a concave surface facing the object side, a meniscus-shaped first positive lens L12 having a convex surface facing the object side, and biconvex lenses arranged in order from the object side. A junction lens consisting of a second positive lens L13 having a shape, a third positive lens L14 having a meniscus shape with a convex surface facing the object side, a fourth positive lens L15 having a biconvex shape, and a second negative lens L16 having a biconcave shape. , And an opening aperture S.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a meniscus-shaped lens L22 having a concave surface facing the object side, arranged in order from the object side. It is composed of a second positive lens L23. The lens surface of the first positive lens L22 on the image plane I side is an aspherical surface.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a biconcave-shaped negative lens L32 arranged in order from the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 30 below lists the values of the specifications of the optical system according to the thirtieth embodiment.

(Table 30)
[Overall specifications]
f 85.00
FNO 1.85
ω 14.2
Y 21.70
TL 115.242
BF 14.943
BFa 14.261
[Lens specifications]
Surface number RD nd νd
1 -74.95148 2.500 1.67270 32.2
2 -131.91024 0.300
3 85.64889 4.000 1.94595 18.0
4 120.40884 0.300
5 115.73186 7.000 1.59282 68.6
6 -191.64403 0.100
7 48.88487 5.000 1.80400 46.6
8 63.21824 0.200
9 40.00000 10.246 1.59282 68.7
10 -287.51510 2.500 1.67270 32.2
11 26.35774 7.011
12 ∞ D12 (variable) (aperture S)
13 -28.44113 1.500 1.64769 33.7
14 -287.07114 1.500
15 102.04030 5.000 1.77377 47.2
16 * -53.66013 1.500
17 -88.84311 4.500 1.49700 81.6
18 -33.17367 D18 (variable)
19 -397.22387 4.000 1.94595 18.0
20 -86.37143 4.578
21 -52.43868 2.000 1.64769 33.7
22 143.09995 11.943
23 ∞ 2.000 1.51680 64.1
24 ∞ D24 (variable)
[Aspherical data]
16th surface κ = 1.0000
A4 = 4.49957E-06, A6 = 4.10925E-09, A8 = -1.26128E-11, A10 = 2.42467E-14
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 85.00 β = -0.1242
D0 ∞ 661.16
D12 20.672 8.633
D18 15.892 27.931
D24 1.000 1.000
[Lens group data]
Focal length
G1 1 134.72
G2 13 74.30
G3 19 -130.08
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) / f = 0.882
Conditional expression (2) f2 / (-f3) = 0.571
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.556
Conditional expression (4) f / f1 = 0.631
Conditional expression (5) f / f2 = 1.144
Conditional expression (6) f1 / f2 = 1.813
Conditional expression (7) BFa / f = 0.168
Conditional expression (8) fF / fR = 1.075
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 3.632
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.766
Conditional expression (11) FNO × (f1 / f) = 2.929
Conditional expression (12) 2ω = 28.4

FIG. 60A is a diagram of various aberrations of the optical system according to the thirtieth embodiment at infinity focusing. FIG. 60B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the thirtieth embodiment. From each aberration diagram, it can be seen that the optical system according to the thirtieth embodiment has various aberrations satisfactorily corrected and has excellent imaging performance.

(31st Example)
The 31st Example will be described with reference to FIGS. 61 to 62 and Table 31. FIG. 61 is a diagram showing a lens configuration in an infinity-focused state of the optical system according to the 31st embodiment of the present embodiment. In the optical system LS (31) according to the 31st embodiment, the first lens group G1 having a positive refractive power, the second lens group G2 having a positive refractive power, and the negative refraction are arranged in order from the object side. It is composed of a third lens group G3 having power. When focusing from an infinity object to a short-distance (finite distance) object, the second lens group G2 moves toward the object along the optical axis, and the first lens group G1 and the third lens group G3 are fixed. ..

The first lens group G1 includes a biconcave first negative lens L11, a biconvex first positive lens L12, a biconvex second positive lens L13, and a biconvex second positive lens L13 arranged in order from the object side. A meniscus-shaped third positive lens L14 with a convex surface, a meniscus-shaped fourth positive lens L15 with a convex surface facing the object side, a biconvex fifth positive lens L16, and a biconcave second negative lens L17. It is composed of a junction lens made of, and an aperture aperture S. The third positive lens L14 has an aspherical lens surface on the object side.

The second lens group G2 has a meniscus-shaped negative lens L21 having a concave surface facing the object side, a biconvex first positive lens L22, and a meniscus-shaped lens L22 having a concave surface facing the object side, arranged in order from the object side. It is composed of a second positive lens L23. The lens surface of the first positive lens L22 on the image plane I side is an aspherical surface.

The third lens group G3 is composed of a meniscus-shaped positive lens L31 having a concave surface facing the object side and a biconcave-shaped negative lens L32 arranged in order from the object side. The image plane I is arranged on the image side of the third lens group G3. An optical filter FL that can be inserted and removed is arranged between the third lens group G3 and the image plane I.

Table 31 below lists the values of the specifications of the optical system according to the 31st embodiment.

(Table 31)
[Overall specifications]
f 85.00
FNO 1.42
ω 14.2
Y 21.70
TL 145.265
BF 14.071
BFa 13.389
[Lens specifications]
Surface number RD nd νd
1 -79.06766 3.000 1.67270 32.2
2 104.61579 5.110
3 243.58488 6.500 1.94595 18.0
4-628.66078 0.300
5 109.12437 16.500 1.59282 68.6
6 -110.85187 0.100
7 * 63.25612 11.500 1.77250 49.6
8 360.60495 0.200
9 52.11101 8.500 1.59282 68.7
10 88.79834 0.200
11 71.03249 8.500 1.59282 68.6
12 -790.77200 2.500 1.85025 30.0
13 30.29304 9.299
14 ∞ D14 (variable) (aperture S)
15 -35.50553 1.500 1.67270 32.2
16 -19114.07500 1.500
17 96.59624 6.000 1.77377 47.2
18 * -65.15132 1.500
19 -154.43166 6.000 1.49700 81.6
20 -40.92465 D20 (variable)
21 -793.09360 4.000 1.94595 18.0
22 -123.62638 9.551
23 -59.68219 2.000 1.64769 33.7
24 388.46258 11.071
25 ∞ 2.000 1.51680 63.9
26 ∞ D26 (variable)
[Aspherical data]
7th page
A4 = -1.31502E-07, A6 = -4.69010E-11, A8 = 1.13722E-14, A10 = -8.34540E-18
Surface 18 κ = 1.0000
A4 = 2.96560E-06, A6 = 2.23513E-09, A8 = -5.41262E-12, A10 = 7.26232E-15
[Variable interval data]
Infinity in-focus state Short-distance in-focus state
f = 85.00 β = -0.1177
D0 ∞ 661.16
D14 23.433 7.955
D20 3.500 18.978
D26 1.000 1.000
[Lens group data]
Focal length
G1 1 117.63
G2 15 83.50
G3 21 -188.48
[Conditional expression correspondence value]
Conditional expression (1) (-G1R1) /f=0.930
Conditional expression (2) f2 / (-f3) = 0.443
Conditional expressions (3), (3-1), (3-2)
(-G1R1) /f1=0.672
Conditional expression (4) f / f1 = 0.723
Conditional expression (5) f / f2 = 1.018
Conditional expression (6) f1 / f2 = 1.409
Conditional expression (7) BFa / f = 0.158
Conditional expression (8) fF / fR = 0.943
Conditional expression (9) (G1R2 + G1R1) / (G1R2-G1R1) = 0.139
Conditional expression (10) {1- (β2) ² } × (β3) ² = 0.510
Conditional expression (11) FNO × (f1 / f) = 1.968
Conditional expression (12) 2ω = 28.4

FIG. 62 (A) is an aberration diagram of the optical system according to the 31st embodiment at infinity focusing. FIG. 62B is a diagram of various aberrations at the time of short-distance (close-distance) focusing of the optical system according to the 31st embodiment. From each aberration diagram, it can be seen that the optical system according to the 31st embodiment has various aberrations corrected well and has excellent imaging performance.

According to each of the above embodiments, it is possible to realize an optical system capable of obtaining good optical performance while suppressing a change in image magnification from an infinity focusing state to a short distance focusing state.

Here, each of the above examples shows a specific example of the present invention, and the present invention is not limited thereto.

The following contents can be appropriately adopted as long as the optical performance of the optical system of the present embodiment is not impaired.

The focusing lens group refers to a portion having at least one lens separated by an air interval that changes during focusing (for example, the second lens group of the present embodiment). That is, a single lens group, a plurality of lens groups, or a partial lens group may be moved in the optical axis direction to focus on a short-range object from an infinity object. This focusing lens group can also be applied to autofocus, and is also suitable for driving a motor for autofocus (using an ultrasonic motor or the like).

In each embodiment of the optical system of the present embodiment, a configuration having no anti-vibration function is shown, but the present application is not limited to this, and a configuration having an anti-vibration function can be used.

The lens surface may be formed on a spherical surface or a flat surface, or may be formed on an aspherical surface. When the lens surface is spherical or flat, lens processing and assembly adjustment are facilitated, and deterioration of optical performance due to processing and assembly adjustment errors can be prevented, which is preferable. Further, even if the image plane is deviated, the depiction performance is less deteriorated, which is preferable.

When the lens surface is aspherical, the aspherical surface is an aspherical surface formed by grinding, a glass mold aspherical surface formed by forming glass into an aspherical shape, or a composite aspherical surface formed by forming resin on the glass surface into an aspherical shape. It doesn't matter which one. Further, the lens surface may be a diffraction surface, and the lens may be a refractive index distribution type lens (GRIN lens) or a plastic lens.

An antireflection film having a high transmittance in a wide wavelength range may be applied to each lens surface in order to reduce flare and ghost and achieve high contrast optical performance. As a result, flare and ghost can be reduced, and high-contrast and high optical performance can be achieved.

G1 1st lens group G2 2nd lens group G3 3rd lens group I image plane S Aperture diaphragm

Claims (17)

It has a first lens group having a positive refractive power, a second lens group having a positive refractive power, and a third lens group having a negative refractive power arranged in order from the object side.
At the time of focusing, the second lens group moves along the optical axis and
An optical system that satisfies the following conditional expression.
-5.000 <(-G1R1) / f <500.000
0.20 <f2 / (-f3) <1.20
However, f2: the focal length of the second lens group f3: the focal length of the third lens group f: the focal length of the optical system G1R1: the object side of the lens component arranged on the most object side of the first lens group. Radical length of the lens surface of The optical system according to claim 1, which satisfies the following conditional expression.
-5.000 <(-G1R1) / f1 <50.000
However, f1: the focal length of the first lens group The optical system according to claim 1, which satisfies the following conditional expression.
0.010 <(-G1R1) /f1 <1.100
However, f1: the focal length of the first lens group The optical system according to claim 1, which satisfies the following conditional expression.
1.000 <(-G1R1) / f1 <50.000
However, f1: the focal length of the first lens group The optical system according to any one of claims 1 to 4, wherein the first lens group has an aperture. The optical system according to any one of claims 1 to 5, wherein the first lens group is fixed at the time of focusing. The optical system according to any one of claims 1 to 6, which satisfies the following conditional expression.
0.010 <f / f1 <5.000
However, f1: the focal length of the first lens group The optical system according to any one of claims 1 to 7, which satisfies the following conditional expression.
0.010 <f / f2 <5.000 The optical system according to any one of claims 1 to 8, which satisfies the following conditional expression.
0.010 <f1 / f2 <5.000
However, f1: the focal length of the first lens group The optical system according to any one of claims 1 to 9, which satisfies the following conditional expression.
0.100 <BFa / f <0.500
However, Bfa: the air conversion distance on the optical axis from the lens surface on the image side to the image surface in the lens arranged on the most image side of the optical system. The optical system according to any one of claims 1 to 10, which satisfies the following conditional expression.
0.10 <fF / fR <3.00
However, fF: the combined focal length of the lens arranged on the object side of the aperture in the optical system fR: the combined focal length of the lens arranged on the image side of the aperture in the optical system. The optical system according to any one of claims 1 to 11, which satisfies the following conditional expression.
-10.0 <(G1R2 + G1R1) / (G1R2-G1R1) <10.0
However, G1R2: radius of curvature of the lens surface on the image side in the lens component arranged on the most object side of the first lens group. The optical system according to any one of claims 1 to 12, which satisfies the following conditional expression.
0.30 << {1- (β2) ² } × (β3) ² <2.00
However, β2: lateral magnification of the second lens group in an infinity focusing state β3: lateral magnification of the third lens group The optical system according to any one of claims 1 to 13, which satisfies the following conditional expression.
0.50 <FNO × (f1 / f) <5.50
However, FNO: F number of the optical system f1: Focal length of the first lens group The optical system according to any one of claims 1 to 14, which satisfies the following conditional expression.
15.0 ° <2ω <85.0 °
However, 2ω: the angle of view of the optical system An optical device including the optical system according to any one of claims 1 to 15. A method for manufacturing an optical system having a first lens group having a positive refractive power, a second lens group having a positive refractive power, and a third lens group having a negative refractive power arranged in order from the object side. There,
At the time of focusing, the second lens group moves along the optical axis and
To satisfy the following conditional expression
A method of manufacturing an optical system in which each lens is arranged in a lens barrel.
-5.000 <(-G1R1) / f <500.000
0.20 <f2 / (-f3) <1.20
However, f2: the focal length of the second lens group f3: the focal length of the third lens group f: the focal length of the optical system G1R1: the object side of the lens component arranged on the most object side of the first lens group. Radical length of the lens surface of

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