Optical system, optical device, and method for manufacturing optical system

Abstract

The optical system is configured to include a first optical system and a second optical system. The first optical system, starting from the object side, sequentially includes a front lens group with negative optical power, a light path branching component with a branching surface, and a first rear lens group for the incidence of first light. The branching surface transmits a portion of the incident light and reflects at least a portion of the incident light that is different from the first portion. The first light is at least a portion of the light reflected from the branching surface. The second optical system, starting from the object side, sequentially includes a front lens group, a light path branching component, and a second rear lens group for the incidence of second light. The second light is at least a portion of the light transmitted from the branching surface. The second optical system has a total focal length different from that of the first optical system.

Description

Technical Field

[0001] This disclosure relates to optical systems, optical devices, and methods for manufacturing optical systems. Background Technology

[0002] An optical device is proposed that separates light from a subject through a photographing lens into visible light and infrared light, so that the visible light image and the infrared light image are imaged at different positions (see, for example, Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2010-102281 Summary of the Invention

[0006] The optical system disclosed herein comprises: a first optical system having, sequentially from the object side, a front lens group having negative optical power, a light path branching component having a branching surface, and a first rear lens group, wherein the branching surface transmits a portion of incident light and reflects at least a portion of the incident light that is different from the portion therein, and the first rear lens group is for incident first light as at least a portion of the light reflected at the branching surface; and a second optical system having, sequentially from the object side, a front lens group, a light path branching component, and a second rear lens group for incident second light, wherein the second light is at least a portion of the light transmitted at the branching surface, and the second optical system having an overall focal length different from that of the first optical system.

[0007] The disclosed method for manufacturing an optical system includes a branching surface that transmits a portion of incident light and reflects at least a portion of the incident light that is different from that portion, and an optical system that images a first light and a second light respectively. The first light is at least a portion of the light reflected by the branching surface, and the second light is at least a portion of the light transmitted by the branching surface. The manufacturing method includes: configuring a first optical system such that, starting from the object side, it sequentially includes a front lens group with negative optical power, a light path branching component having the branching surface, and a first rear lens group for the first light to be incident; configuring a second optical system such that, starting from the object side, it sequentially includes a front lens group, a light path branching component, and a second rear lens group for the second light to be incident; and configuring the second optical system to have an overall focal length different from that of the first optical system. Attached Figure Description

[0008] Figure 1 This is a schematic diagram illustrating an example of the overall structure of the optical system according to this embodiment.

[0009] Figure 2This is a cross-sectional view of the first optical system of the first embodiment.

[0010] Figure 3 The image shows the aberrations of the first optical system as described in the first embodiment.

[0011] Figure 4 This is a cross-sectional view of the second optical system having the optical system of the first embodiment.

[0012] Figure 5 The image shows the aberrations of the second optical system, which is the optical system of the first embodiment.

[0013] Figure 6 This is a cross-sectional view of the first optical system, which is the optical system of the second embodiment.

[0014] Figure 7 The aberration diagrams of the first optical system are present in the optical system of the second embodiment.

[0015] Figure 8 This is a cross-sectional view of the second optical system of the second embodiment.

[0016] Figure 9 This is a diagram of the aberrations of the second optical system as described in the second embodiment.

[0017] Figure 10 This is a cross-sectional view of the first optical system, which is the optical system of the third embodiment.

[0018] Figure 11 The aberration diagrams of the first optical system are shown in the optical system of the third embodiment.

[0019] Figure 12 This is a cross-sectional view of the second optical system, which is the optical system of the third embodiment.

[0020] Figure 13 The aberration diagrams of the second optical system are shown in the optical system of the third embodiment.

[0021] Figure 14 This is a cross-sectional view of the first optical system of the optical system in the fourth embodiment.

[0022] Figure 15 The aberration diagrams of the first optical system are shown in the optical system of the fourth embodiment.

[0023] Figure 16 This is a cross-sectional view of the second optical system of the optical system in the fourth embodiment.

[0024] Figure 17 The aberration diagrams of the second optical system are shown in the optical system of the fourth embodiment.

[0025] Figure 18 This is a cross-sectional view of the first optical system of the optical system in the fifth embodiment.

[0026] Figure 19 The image shows the aberrations of the first optical system, which is the optical system of the fifth embodiment.

[0027] Figure 20 This is a cross-sectional view of the second optical system of the optical system in the fifth embodiment.

[0028] Figure 21 The image shows the aberrations of the second optical system, which is the optical system of the fifth embodiment.

[0029] Figure 22 This is a cross-sectional view of the first optical system of the optical system of the sixth embodiment.

[0030] Figure 23 The aberration diagrams of the first optical system are shown in the optical system of the sixth embodiment.

[0031] Figure 24 This is a cross-sectional view of the second optical system of the optical system in the sixth embodiment.

[0032] Figure 25 The aberration diagrams of the second optical system are shown in the optical system of the sixth embodiment.

[0033] Figure 26 This is a schematic diagram illustrating the overall structure of the optical system in the seventh embodiment.

[0034] Figure 27 This is a cross-sectional view of the first optical system of the optical system of the seventh embodiment.

[0035] Figure 28 The aberration diagrams of the first optical system are shown in the optical system of the seventh embodiment.

[0036] Figure 29 This is a cross-sectional view of the second optical system of the optical system in the seventh embodiment.

[0037] Figure 30 This is a diagram of the aberrations of the second optical system, which is the optical system of the seventh embodiment.

[0038] Figure 31 This is a schematic diagram illustrating the overall structure of the optical system in the 8th embodiment.

[0039] Figure 32 This is a cross-sectional view of the first optical system of the optical system of the 8-1 embodiment.

[0040] Figure 33 The image shows the aberrations of the first optical system as described in the optical system of embodiment 8-1.

[0041] Figure 34 This is a cross-sectional view of the second optical system of the optical system in the 8-1 embodiment.

[0042] Figure 35 The aberration diagrams of the second optical system are shown in the optical system of the 8-1 embodiment.

[0043] Figure 36 This is a cross-sectional view of the first optical system of the optical system in the 8-2 embodiment.

[0044] Figure 37 The aberration diagrams of the first optical system are shown in the optical system of the 8-2 embodiment.

[0045] Figure 38 This is a cross-sectional view of the second optical system of the optical system in the 8-2 embodiment.

[0046] Figure 39 The image shows the aberrations of the second optical system as described in the optical system of embodiment 8-2.

[0047] Figure 40 This is a cross-sectional view of the second optical system of the optical system in the 9-1 embodiment.

[0048] Figure 41 The aberration diagrams of the second optical system are shown in the optical system of the 9-1 embodiment.

[0049] Figure 42 This is a cross-sectional view of the second optical system of the optical system in the 9-2 embodiment.

[0050] Figure 43 The image shows the aberrations of the second optical system as described in the optical system of embodiment 9-2.

[0051] Figure 44 This is a cross-sectional view of the first optical system of the optical system of the 10th embodiment.

[0052] Figure 45 The aberration diagrams of the first optical system are shown in the optical system of the tenth embodiment.

[0053] Figure 46 This is a cross-sectional view of the second optical system of the optical system in the 10th embodiment.

[0054] Figure 47 The aberration diagrams of the second optical system are shown in the optical system of the 10th embodiment.

[0055] Figure 48 This is a schematic diagram of an optical device equipped with the optical system of this embodiment.

[0056] Figure 49 This diagram illustrates an example of the operation of the drive unit in the optical device of this embodiment.

[0057] Figure 50 This is a diagram illustrating an example of image information generated by the optical device of this embodiment.

[0058] Figure 51 This is a flowchart illustrating a general method for manufacturing the optical system according to this embodiment. Detailed Implementation

[0059] The optical system, optical device, and manufacturing method of the optical system according to the embodiments of this application will be described below.

[0060] Figure 1 This is a schematic diagram illustrating an example of the overall structure of the optical system according to this embodiment.

[0061] The optical system 1 of this embodiment has a first optical system OS1, which, starting from the object side, sequentially includes a front lens group GF, a light path branching component OB having a branching surface BP1, and a first rear lens group GR1 for incident light that is input to the front lens group GF and the light path branching component OB and reflected at the branching surface BP1. Additionally, the optical system 1 of this embodiment has a second optical system OS2, which, starting from the object side, sequentially includes a front lens group GF, a light path branching component OB, and a second rear lens group GR2 for incident light that is incident on the front lens group GF and the light path branching component OB and reflected at the branching surface BP1. The front lens group GF has negative optical power.

[0062] exist Figure 1 In the illustration, the first optical axis AX1 of the first optical system OS1 and the second optical axis AX2 of the second optical system OS2 are described as not overlapping each other at positions closer to the object side than the branch plane BP.

[0063] In the optical system 1 of this embodiment, light emitted from the front lens group GF is incident on the optical path branching component OB. The optical path branching component OB is a cubic beam splitter (prism) with a branching surface BP1, which transmits a portion of the incident light and reflects at least a portion of the incident light that is different from that portion. The optical path branching component OB can also be a flat beam splitter (half-reflector) with a branching surface BP1.

[0064] In the first optical system OS1 of the optical system 1 of this embodiment, light emitted from the front lens group GF and incident on the light path branching member OB is reflected at the branching surface BP1 and incident on the first rear lens group GR1, forming an image on the first image plane I1. In the second optical system OS2 of the optical system 1 of this embodiment, light emitted from the front lens group GF and incident on the light path branching member OB is transmitted through the branching surface BP1 and incident on the second rear lens group GR2, forming an image on the second image plane I2.

[0065] In the optical system 1 of this embodiment, the second optical system OS2 has a total system focal length that is different from that of the first optical system OS1.

[0066] The optical system 1 of this embodiment has a negative optical power through the front lens group GF, which can sufficiently increase the field of view of the wide-angle side optical system, which is the one with the shorter overall focal length in the first optical system OS1 and the second optical system OS2. Furthermore, while sufficiently increasing the magnification of the telephoto side optical system, which is the one with the longer overall focal length in the first optical system OS1 and the second optical system OS2, the light incident through each optical system is properly imaged.

[0067] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0068] (1) 1.20 < fB / fA < 13.00

[0069] in,

[0070] fB: The longer of the total focal length of the first optical system OS1 and the total focal length of the second optical system OS2.

[0071] fA: The shorter of the total focal length of the first optical system OS1 and the total focal length of the second optical system OS2.

[0072] Condition (1) specifies the ratio of the total focal length of the telephoto optical system to the total focal length of the wide-angle optical system. By satisfying condition (1), the optical system 1 of this embodiment can sufficiently increase the field of view of the wide-angle optical system, and while sufficiently increasing the magnification of the telephoto optical system, it can appropriately correct various aberrations.

[0073] When the value of condition (1) in the optical system 1 of this embodiment exceeds the upper limit, the field of view of the wide-angle side optical system cannot be sufficiently increased, and the magnification of the telephoto side optical system cannot be sufficiently increased.

[0074] In the optical system 1 of this embodiment, by setting the upper limit value of conditional expression (1) to 13.00, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit value of conditional expression (1) to 12.55, 12.05, 11.62, 11.16, 10.70, and more preferably to 10.00.

[0075] Furthermore, when the value of conditional expression (1) in the optical system 1 of this embodiment is lower than the lower limit, it becomes difficult to properly correct various aberrations such as axial chromatic aberration, magnification chromatic aberration, and distortion.

[0076] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (1) to 1.20, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (1) to 1.35, 1.50, 1.65, 1.80, 1.95, and more preferably to 2.00.

[0077] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0078] (2) 0.20 < -fF / fA < 10.00

[0079] in,

[0080] fF: Focal length of the front lens group GF

[0081] fA: The shorter of the total focal length of the first optical system OS1 and the total focal length of the second optical system OS2.

[0082] Condition (2) specifies the ratio of the focal length of the front lens group GF to the total focal length of the wide-angle optical system. By satisfying condition (2), the optical system 1 of this embodiment can appropriately correct various aberrations.

[0083] When the value of conditional expression (2) in the optical system 1 of this embodiment exceeds the upper limit, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and distortion.

[0084] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (2) to 10.00, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (2) to 9.60, 9.20, 8.805, 8.40, 8.00, and more preferably to 7.00.

[0085] Furthermore, when the value of conditional expression (2) in the optical system 1 of this embodiment is lower than the lower limit, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and distortion.

[0086] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (2) to 0.20, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (2) to 0.26, 0.32, 0.38, 0.44, 0.50, and more preferably to 1.00.

[0087] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0088] (3) 0.05 < -fF / fB < 3.50

[0089] in,

[0090] fF: Focal length of the front lens group GF

[0091] fB: The longer of the total focal length of the first optical system OS1 and the total focal length of the second optical system OS2.

[0092] Condition (3) specifies the ratio of the focal length of the front lens group GF to the focal length of the telephoto optical system. By satisfying condition (3), the optical system 1 of this embodiment can appropriately correct various aberrations while suppressing the increase of the total optical length.

[0093] When the value of conditional expression (3) in the optical system 1 of this embodiment exceeds the upper limit, it becomes difficult to properly correct various aberrations such as field curvature and astigmatism.

[0094] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (3) to 3.50, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (3) to 3.30, 3.10, 2.90, 2.70, 2.50, and more preferably to 2.00.

[0095] Furthermore, when the value of conditional equation (3) in the optical system 1 of this embodiment is lower than the lower limit, the negative optical power of the front lens group GF becomes too strong. In addition, the overall focal length of the telescope optical system becomes longer, and the overall optical length of the telescope optical system increases. Furthermore, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, axial chromatic aberration, and magnification chromatic aberration.

[0096] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (3) to 0.05, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (3) to 0.06, 0.07, 0.08, 0.09, 0.10, and more preferably to 0.20.

[0097] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0098] (4) 3.50 < -f1 / fA < 50.30

[0099] in,

[0100] f1: The focal length of the lens in the front lens group (GF) positioned closest to the object.

[0101] fA: The shorter of the total focal length of the first optical system OS1 and the total focal length of the second optical system OS2.

[0102] Condition (4) specifies the ratio of the focal length of the lens in the front lens group GF positioned closest to the object to the focal length of the wide-angle optical system. By satisfying condition (4), the optical system 1 of this embodiment can appropriately correct various aberrations while suppressing the enlargement of the lens in the front lens group GF positioned closest to the object.

[0103] When the value of conditional expression (4) in the optical system 1 of this embodiment exceeds the upper limit, the lens of the front lens group GF is arranged at the position closest to the object, making it difficult to properly correct various aberrations such as field curvature, astigmatism, and distortion.

[0104] In the optical system 1 of this embodiment, by setting the upper limit value of conditional expression (4) to 50.30, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit value of conditional expression (4) to 49.00, 46.00, 43.00, 40.00, and more preferably to 36.00.

[0105] Furthermore, when the value of conditional expression (4) in the optical system 1 of this embodiment is lower than the lower limit, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and distortion.

[0106] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (4) to 3.50, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (4) to 3.74, 3.98, 4.22, 4.46, 4.70, and more preferably to 6.50.

[0107] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0108] (5) 0.25 < -f1 / fB < 15.00

[0109] in,

[0110] f1: The focal length of the lens in the front lens group (GF) positioned closest to the object.

[0111] fB: The longer of the total focal length of the first optical system OS1 and the total focal length of the second optical system OS2.

[0112] Condition (5) specifies the ratio of the focal length of the lens in the front lens group GF positioned closest to the object to the focal length of the telescopic optical system. By satisfying condition (5), the optical system 1 of this embodiment can appropriately correct various aberrations while suppressing the enlargement of the lens in the front lens group GF positioned closest to the object and the increase in the total optical length.

[0113] When the value of conditional expression (5) in the optical system 1 of this embodiment exceeds the upper limit, the lens of the front lens group GF, which is positioned closest to the object, becomes larger, making it difficult to properly correct various aberrations such as field curvature and astigmatism.

[0114] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (5) to 15.00, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (5) to 14.40, 13.80, 13.20, 12.60, 12.00, and more preferably to 11.50.

[0115] Furthermore, when the value of conditional expression (5) in the optical system 1 of this embodiment is lower than the lower limit, the negative optical power of the front lens group GF becomes too strong. In addition, the overall focal length of the telescope optical system becomes longer, and the overall optical length of the telescope optical system increases. Furthermore, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, axial chromatic aberration, and magnification chromatic aberration.

[0116] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (5) to 0.25, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (5) to 0.30, 0.35, 0.40, 0.45, 0.50, and more preferably to 1.00.

[0117] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0118] (6) 0.04 < -D12 / f1 < 1.50

[0119] in,

[0120] D12: The distance on the optical axis between the image-side lens surface of the lens of the front lens group GF positioned closest to the object and the object-side lens surface of the lens adjacent to the image-side lens of the front lens group GF positioned closest to the object.

[0121] f1: The focal length of the lens in the front lens group GF positioned closest to the object.

[0122] Condition (6) specifies the ratio of the distance on the optical axis between the lens of the front lens group GF positioned closest to the object and the lens adjacent to it on the image plane side to the focal length of the lens of the front lens group GF positioned closest to the object. By satisfying condition (6), the optical system 1 of this embodiment can appropriately correct various aberrations while suppressing the enlargement of the lens of the front lens group GF positioned closest to the object and the increase in the total optical length.

[0123] When the value of conditional expression (6) in the optical system 1 of this embodiment exceeds the upper limit, the lens of the front lens group GF, which is positioned closest to the object, will become larger, the total optical length of the wide-angle and telephoto optical systems will increase, and proper correction of various aberrations such as field curvature, coma, and magnification chromatic aberration will become difficult.

[0124] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (6) to 1.50, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (6) to 1.44, 1.38, 1.32, 1.26, 1.20, and more preferably to 0.85.

[0125] Furthermore, when the value of conditional expression (6) in the optical system 1 of this embodiment is lower than the lower limit, it becomes difficult to properly correct various aberrations such as field curvature, coma, and magnification chromatic aberration.

[0126] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (6) to 0.04, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (6) to 0.05, 0.06, 0.07, 0.08, 0.09, and more preferably to 0.11.

[0127] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0128] (7) 0.30 < TLB / TLA < 3.50

[0129] in,

[0130] TLB: The total optical length of the optical system with the longer overall focal length in optical system OS1 (first optical system) and OS2 (second optical system).

[0131] TLA: The total optical length of the optical system with the shorter overall focal length in optical system OS1 (first optical system) and OS2 (second optical system).

[0132] Condition (7) specifies the ratio of the total optical length of the telephoto optical system to the total optical length of the wide-angle optical system. By satisfying condition (7), the optical system 1 of this embodiment can appropriately correct various aberrations while suppressing the increase of the total optical length.

[0133] When the value of conditional expression (7) in the optical system 1 of this embodiment exceeds the upper limit, the total optical length of the telephoto optical system increases. In addition, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and distortion in the wide-angle optical system.

[0134] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (7) to 3.50, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (7) to 3.30, 3.10, 2.90, 2.70, 2.50, and more preferably to 2.25.

[0135] Furthermore, when the value of conditional expression (7) in the optical system 1 of this embodiment is lower than the lower limit, the total optical length of the wide-angle side optical system increases. In addition, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and coma in the wide-angle side optical system.

[0136] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (7) to 0.30, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (7) to 0.38, 0.46, 0.54, 0.62, 0.70, and more preferably to 0.85.

[0137] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0138] (8) 0.30<-(r12+r11) / (r12-r11)<4.70

[0139] in,

[0140] r12: The radius of curvature of the lens surface on the image plane side of the lens group GF, which is positioned closest to the object.

[0141] r11: The radius of curvature of the lens surface on the object side of the front lens group GF, positioned closest to the object side.

[0142] Condition (8) specifies the shape factor of the lens in which the front lens group GF is positioned closest to the object. By satisfying condition (8), the optical system 1 of this embodiment can appropriately correct various aberrations such as field curvature, astigmatism, distortion, and coma.

[0143] When the value of conditional expression (8) in the optical system 1 of this embodiment exceeds the upper limit, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and distortion.

[0144] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (8) to 4.70, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (8) to 4.60, 4.50, 4.40, 4.30, 4.20, and more preferably to 3.50.

[0145] Furthermore, when the value of conditional expression (8) in the optical system 1 of this embodiment is lower than the lower limit, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and coma.

[0146] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (8) to 0.30, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (8) to 0.34, 0.38, 0.42, 0.46, 0.50, and more preferably to 0.90.

[0147] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0148] (9) 0.10<(r21+r12) / (r21-r12)<3.30

[0149] in,

[0150] r21: The radius of curvature of the lens surface on the object side of the lens adjacent to the image plane of the lens of the front lens group GF, which is positioned closest to the object side.

[0151] r12: The radius of curvature of the lens surface on the image plane side of the lens group GF, which is positioned closest to the object.

[0152] Condition (9) specifies the shape factor of the air lens, which is configured between the lens of the front lens group GF positioned closest to the object and the lens of the front lens group GF positioned closest to the object on the image plane side. The optical system 1 of this embodiment can appropriately correct various aberrations such as field curvature and astigmatism by satisfying condition (9).

[0153] When the value of conditional expression (9) in the optical system 1 of this embodiment exceeds the upper limit, it becomes difficult to properly correct various aberrations such as field curvature and astigmatism.

[0154] In the optical system 1 of this embodiment, by setting the upper limit value of conditional expression (9) to 3.30, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit value of conditional expression (9) to 3.00, 2.90, 2.60, 2.30, and more preferably to 2.00.

[0155] Furthermore, when the value of conditional expression (9) in the optical system 1 of this embodiment is lower than the lower limit, it becomes difficult to properly correct various aberrations such as field curvature and astigmatism.

[0156] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (9) to 0.10, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (9) to 0.14, 0.18, 0.22, 0.26, and more preferably to 0.29.

[0157] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0158] (10) 0.30<D12 / fA<11.30

[0159] in,

[0160] D12: The distance on the optical axis between the image-side lens surface of the lens of the front lens group GF positioned closest to the object and the object-side lens surface of the lens adjacent to the image-side lens of the front lens group GF positioned closest to the object.

[0161] fA: The shorter of the total focal length of the first optical system OS1 and the total focal length of the second optical system OS1.

[0162] Condition (10) specifies the ratio of the distance on the optical axis between the lens of the front lens group GF positioned closest to the object side and the lens adjacent to it on the image plane side to the total focal length of the wide-angle optical system. By satisfying condition (10), the optical system 1 of this embodiment can appropriately correct various aberrations while suppressing the increase in the total optical length.

[0163] When the value of conditional expression (10) in the optical system 1 of this embodiment exceeds the upper limit, the total optical length of the wide-angle side optical system increases. In addition, it becomes difficult to properly correct various aberrations such as field curvature and coma.

[0164] In the optical system 1 of this embodiment, by setting the upper limit value of conditional expression (10) to 11.30, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit value of conditional expression (10) to 10.80, 10.30, 9.80, 9.30, 8.85, and more preferably to 8.40.

[0165] Furthermore, when the value of conditional expression (10) in the optical system 1 of this embodiment is lower than the lower limit, it becomes difficult to properly correct various aberrations, such as coma.

[0166] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (10) to 0.30, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (10) to 0.35, 0.40, 0.45, 0.50, 0.55, and more preferably to 1.00.

[0167] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0168] (11) 0.07 < D12 / fB < 4.30

[0169] in,

[0170] D12: The distance on the optical axis between the image-side lens surface of the lens of the front lens group GF positioned closest to the object and the object-side lens surface of the lens adjacent to the image-side lens of the front lens group GF positioned closest to the object.

[0171] fB: The longer of the total focal length of the first optical system OS1 and the total focal length of the second optical system OS2.

[0172] Condition (11) specifies the ratio of the distance on the optical axis between the lens of the front lens group GF positioned closest to the object side and the lens adjacent to it on the image plane side to the total focal length of the telescopic optical system. By satisfying condition (11), the optical system 1 of this embodiment can appropriately correct various aberrations while suppressing the increase in the total optical length.

[0173] When the value of conditional expression (11) of the optical system 1 in this embodiment exceeds the upper limit, the total optical length of the telescope-side optical system increases. In addition, it becomes difficult to properly correct various aberrations such as field curvature and coma.

[0174] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (11) to 4.30, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (11) to 4.05, 3.80, 3.55, 3.30, 3.00, and more preferably to 2.70.

[0175] Furthermore, when the value of conditional expression (11) in the optical system 1 of this embodiment is lower than the lower limit, it becomes difficult to properly correct various aberrations such as coma, axial chromatic aberration, and magnification chromatic aberration.

[0176] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (11) to 0.07, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (11) to 0.08, 0.09, 0.11, 0.12, 0.13, and more preferably to 0.35.

[0177] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0178] (12) 1.20<ωA / ωB<15.00

[0179] in,

[0180] ωA: The half field of view of the optical system with the shorter overall focal length in optical system OS1 (first optical system) and OS2 (second optical system).

[0181] ωB: The half field of view of the optical system with the longer overall focal length in optical system OS1 (first optical system) and OS2 (second optical system).

[0182] Condition (12) specifies the ratio of the half field of view of the wide-angle side optical system to the half field of view of the telephoto side optical system. By satisfying condition (12), the optical system 1 of this embodiment can sufficiently increase the field of view of the wide-angle side optical system, and while sufficiently increasing the magnification of the telephoto side optical system, it can appropriately correct various aberrations.

[0183] When the value of conditional expression (12) in the optical system 1 of this embodiment exceeds the upper limit, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and distortion in the wide-angle side optical system, and it also becomes difficult to properly correct various aberrations such as field curvature, astigmatism, axial chromatic aberration, and magnification chromatic aberration in the telephoto side optical system.

[0184] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (12) to 15.00, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (12) to 14.60, 14.20, 13.80, 13.40, 13.00, and more preferably to 11.40.

[0185] Furthermore, when the value of conditional expression (12) in the optical system 1 of this embodiment is lower than the lower limit, it is not possible to sufficiently increase the magnification of the telephoto optical system while simultaneously increasing the field of view of the wide-angle side optical system.

[0186] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (12) to 1.20, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (12) to 1.31, 1.42, 1.53, 1.64, 1.75, and more preferably to 2.00.

[0187] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0188] (13) 0.20<fpA / fpB<2.50

[0189] in,

[0190] fpA: The combined focal length of the positive lens elements continuously arranged on the image plane side, starting from the positive lens element positioned closest to the object side, within the rear lens group of the first rear lens group GR1 and the second rear lens group GR2, and the optical system of the first optical system OS1 and the second optical system OS2 with the shorter overall system focal length.

[0191] fpB: The combined focal length of the positive lens elements continuously arranged on the image plane side, starting from the positive lens element positioned closest to the object side, within the rear lens group of the first rear lens group GR1 and the second rear lens group GR2, and the optical system with the longer overall focal length in the first optical system OS1 and the second optical system OS2.

[0192] Condition (13) specifies the ratio of the combined focal length of the positive lens elements continuously arranged on the image plane side, starting from the positive lens element positioned closest to the object, in the rear lens group included in the wide-angle optical system, to the combined focal length of the positive lens elements continuously arranged on the image plane side, starting from the positive lens element positioned closest to the object, in the rear lens group included in the telephoto optical system. The optical system 1 of this embodiment can appropriately correct various aberrations by satisfying condition (13).

[0193] When the value of conditional expression (13) in the optical system 1 of this embodiment exceeds the upper limit, it becomes difficult to properly correct various aberrations such as spherical aberration and coma.

[0194] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (13) to 2.50, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (13) to 2.40, 2.30, 2.20, 2.10, and more preferably to 2.00.

[0195] Furthermore, when the value of conditional expression (13) in the optical system 1 of this embodiment is lower than the lower limit, it becomes difficult to properly correct various aberrations such as spherical aberration and coma.

[0196] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (13) to 0.20, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (13) to 0.24, 0.28, 0.32, 0.36, and more preferably to 0.40.

[0197] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0198] (14) 0.33<|fRB / fRA|<65.00

[0199] in,

[0200] fRB: The focal length of the rear lens group included in the optical system with the longer overall focal length between the first rear lens group GR1 and the second rear lens group GR2, and between the first optical system OS1 and the second optical system OS2.

[0201] fRA: The focal length of the rear lens group included in the optical system with the shorter overall focal length between the first rear lens group GR1 and the second rear lens group GR2, and between the first optical system OS1 and the second optical system OS2.

[0202] Condition (14) specifies the ratio of the focal length of the rear lens group included in the telephoto optical system to the focal length of the rear lens group included in the wide-angle optical system. The optical system 1 of this embodiment can appropriately correct various aberrations by satisfying condition (14).

[0203] When the value of conditional expression (14) in the optical system 1 of this embodiment exceeds the upper limit, it becomes difficult to properly correct various aberrations such as spherical aberration and coma.

[0204] In the optical system 1 of this embodiment, by setting the upper limit value of conditional expression (14) to 65.00, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit value of conditional expression (14) to 63.70, 62.40, 61.10, 59.80, 58.50, and more preferably to 50.50.

[0205] Furthermore, when the value of conditional expression (14) in the optical system 1 of this embodiment is lower than the lower limit, it becomes difficult to properly correct various aberrations such as spherical aberration and coma.

[0206] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (14) to 0.33, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (14) to 0.39, 0.45, 0.51, 0.57, 0.63, and more preferably to 0.75.

[0207] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0208] (15) 7.00<TLB / fA<110.00

[0209] in,

[0210] TLB: The total optical length of the optical system with the longer overall focal length in optical system OS1 (first optical system) and OS2 (second optical system).

[0211] fA: The shorter of the total focal length of the first optical system OS1 and the total focal length of the second optical system OS2.

[0212] Condition (15) specifies the ratio of the total optical length of the telephoto optical system to the total focal length of the wide-angle optical system. By satisfying condition (15), the optical system 1 of this embodiment can appropriately correct various aberrations while suppressing the increase of the total optical length.

[0213] In the optical system 1 of this embodiment, when the value of conditional expression (15) exceeds the upper limit, the total optical length of the telescope-side optical system increases. In addition, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and coma.

[0214] In the optical system 1 of this embodiment, by setting the upper limit value of conditional expression (15) to 110.00, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit value of conditional expression (15) to 107.50, 105.00, 102.50, 100.00, and more preferably to 97.50.

[0215] Furthermore, in the optical system 1 of this embodiment, when the value of conditional expression (15) is lower than the lower limit, it becomes difficult to properly correct various aberrations such as distortion, field curvature, and astigmatism, especially in the wide-angle side optical system.

[0216] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (15) to 7.00, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (15) to 8.16, 9.32, 10.48, 11.64, 12.80, and more preferably to 20.00.

[0217] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0218] (16) 0.30<TLA / fB<20.50

[0219] in,

[0220] TLA: The total optical length of the optical system with the shorter overall focal length in optical system OS1 (first optical system) and OS2 (second optical system).

[0221] fB: The longer of the total focal length of the first optical system OS1 and the total focal length of the second optical system OS2.

[0222] Condition (16) specifies the ratio of the total optical length of the wide-angle optical system to the total focal length of the telephoto optical system. By satisfying condition (16), the optical system 1 of this embodiment can appropriately correct various aberrations while suppressing the increase of the total optical length.

[0223] In the optical system 1 of this embodiment, when the value of conditional expression (16) exceeds the upper limit, the total optical length of the wide-angle side optical system increases. In addition, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and coma.

[0224] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (16) to 20.50, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (16) to 19.80, 19.10, 18.40, 17.80, and more preferably to 16.50.

[0225] Furthermore, in the optical system 1 of this embodiment, when the value of conditional expression (16) is lower than the lower limit, it becomes difficult to properly correct various aberrations, such as field curvature, astigmatism, axial chromatic aberration, and magnification chromatic aberration, especially in the telescope-side optical system.

[0226] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (16) to 0.30, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (16) to 0.35, 0.40, 0.45, 0.50, 0.55, and more preferably to 2.05.

[0227] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0228] (17) 1.70 < nd1 < 2.01

[0229] in,

[0230] nd1: The refractive index of the lens relative to the d-line of the lens in the front lens group GF positioned closest to the object.

[0231] Condition (17) specifies the refractive index of the lens with respect to the d-line in which the front lens group GF is positioned closest to the object. The optical system 1 of this embodiment can appropriately correct various aberrations by satisfying condition (17).

[0232] In the optical system 1 of this embodiment, when the value of condition (17) exceeds the upper limit, the freedom of choice in selecting the glass material used in the lens is reduced, and color correction becomes difficult.

[0233] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (17) to 2.01, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (17) to 1.97, 1.93, 1.88, 1.84, and more preferably to 1.80.

[0234] Furthermore, in the optical system 1 of this embodiment, when the value of conditional expression (17) is lower than the lower limit, the optical power of the lens of the front lens group GF, which is located at the position closest to the object, becomes weaker, especially in the wide-angle optical system, making field curvature correction difficult.

[0235] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (17) to 1.70, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (17) to 1.71.

[0236] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0237] (18) 1.50 < nd2 < 2.01

[0238] in,

[0239] nd2: The refractive index of the lens with respect to the d-line of the lens adjacent to the lens positioned closest to the object side in the front lens group GF.

[0240] Condition (18) specifies the refractive index of the lens with respect to the d-line of the lens adjacent to the lens positioned closest to the object side of the front lens group GF. The optical system 1 of this embodiment can appropriately correct various aberrations by satisfying condition (18).

[0241] In the optical system 1 of this embodiment, when the value of condition (18) exceeds the upper limit, the freedom of choice in selecting the glass material used in the lens is reduced, and color correction becomes difficult.

[0242] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (18) to 2.01, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (18) to 1.95, 1.89, 1.82, 1.76, and more preferably to 1.70.

[0243] Furthermore, in the optical system 1 of this embodiment, when the value of conditional expression (18) is lower than the lower limit, the optical power of the lens arranged adjacent to the image plane side of the lens of the front lens group GF at the position closest to the object becomes weak, especially in the wide-angle optical system, the field curvature correction becomes difficult.

[0244] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (18) to 1.50, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (18) to 1.55.

[0245] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0246] (19) 1.55 < ndaveF < 2.01

[0247] in,

[0248] ndaveF: The average refractive index of the lens with respect to the d-line of the front lens group GF.

[0249] Condition (19) specifies the average refractive index of the lens with respect to the d-line of the front lens group GF. The optical system 1 of this embodiment can appropriately correct various aberrations by satisfying condition (19).

[0250] In the optical system 1 of this embodiment, when the value of condition (19) exceeds the upper limit, the degree of freedom in selecting the glass material used in the lens of the front lens GF is reduced, and color correction becomes difficult.

[0251] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (19) to 2.01, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (19) to 1.95, 1.89, 1.83, 1.77, and more preferably to 1.71.

[0252] Furthermore, in the optical system 1 of this embodiment, when the value of conditional expression (19) is lower than the lower limit, it becomes difficult to correct each aberration.

[0253] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (19) to 1.55, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (19) to 1.55, 1.57, 1.59, 1.61, 1.63, and more preferably to 1.65.

[0254] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0255] (20) 45°<ωA<120°

[0256] in,

[0257] ωA: The half field of view of the optical system with the shorter overall focal length in optical system OS1 (first optical system) and OS2 (second optical system).

[0258] Condition (20) specifies the half field of view of the wide-angle side optical system. By satisfying condition (20), the optical system 1 of this embodiment can significantly increase the field of view of the wide-angle side optical system while effectively correcting various aberrations such as field curvature, astigmatism, and distortion.

[0259] In the optical system 1 of this embodiment, when the value of condition (20) exceeds the upper limit, it becomes difficult to properly correct various aberrations such as field curvature, astigmatism, and distortion.

[0260] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (20) to 120°, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (20) to 118°, 115°, 110°, 105°, and more preferably to 100°.

[0261] Furthermore, in the optical system 1 of this embodiment, when the value of condition (20) is lower than the lower limit, the field of view of the wide-angle side optical system cannot be sufficiently increased.

[0262] In the optical system 1 of this embodiment, by setting the lower limit of conditional expression (20) to 45°, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit of conditional expression (20) to 50°, 55°, 60°, 65°, and more preferably to 70°.

[0263] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0264] (21) 3°<ωB<30°

[0265] in,

[0266] ωB: The half field of view of the optical system with the longer overall focal length in optical system OS1 (first optical system) and OS2 (second optical system).

[0267] Condition (21) specifies the half field of view of the telescope-side optical system. By satisfying condition (21), the optical system 1 of this embodiment can significantly increase the magnification of the telescope-side optical system while effectively correcting chromatic aberration.

[0268] In the optical system 1 of this embodiment, when the value of condition (21) exceeds the upper limit, the magnification of the telescope optical system cannot be sufficiently increased.

[0269] In the optical system 1 of this embodiment, by setting the upper limit of conditional expression (21) to 30°, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit of conditional expression (21) to 28°, 26°, 24°, 22°, and more preferably to 20°.

[0270] Furthermore, in the optical system 1 of this embodiment, when the value of conditional expression (21) is lower than the lower limit, the color difference cannot be properly corrected.

[0271] In the optical system 1 of this embodiment, by setting the lower limit of conditional expression (21) to 3°, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit of conditional expression (21) to 4°, 5°, 6°, 7°, and more preferably to 8°.

[0272] The optical system 1 of this embodiment preferably satisfies the following conditional expression.

[0273] (22) 0.10<Wi / (1-Wi)≤1.00

[0274] in,

[0275] Wi: The reflectivity of the optical path of the shorter focal length in the first optical system OS1 and the second optical system OS2 when reflected by the branch plane BP, and the transmittance of the optical path of the shorter focal length in the first optical system OS1 and the second optical system OS2 when transmitted by the branch plane BP.

[0276] Condition (22) specifies the ratio of the reflectivity or transmittance of the optical path of the wide-angle side optical system when reflected or transmitted at the branch plane BP to the ratio of the proportion of the optical path of the wide-angle side optical system that is not reflected or transmitted when reflected or transmitted at the branch plane BP, respectively. By satisfying condition (22), the optical system 1 of this embodiment can keep the difference between the brightness of the image formed on the image plane by the wide-angle side optical system with a smaller F-value and the brightness of the image formed on the image plane by the telephoto side optical system with a larger F-value within an appropriate range.

[0277] In the optical system 1 of this embodiment, when the value of condition (22) exceeds the upper limit, the image formed on the image plane by the telescope side optical system will be too dark.

[0278] In the optical system 1 of this embodiment, by setting the upper limit value of conditional expression (22) to 1.00, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the upper limit value of conditional expression (22) to 0.94, 0.88, 0.82, 0.76, and more preferably to 0.70.

[0279] Furthermore, in the optical system 1 of this embodiment, when the value of condition (22) is lower than the lower limit, the image formed on the image plane by the wide-angle side optical system will be too dark.

[0280] In the optical system 1 of this embodiment, by setting the lower limit value of conditional expression (22) to 0.10, the effect of this embodiment can be made more reliable. In addition, in order to make the effect of this embodiment more reliable, it is preferable to set the lower limit value of conditional expression (22) to 0.11.

[0281] In the optical system 1 of this embodiment, the optical path branching component OB is preferably a prism.

[0282] The optical system 1 of this embodiment with this structure can properly correct field curvature, and in addition, can improve the accuracy of the branching surface BP1 of the optical path branching component OB.

[0283] In the optical system 1 of this embodiment, it is preferable that the lens of the front lens group GF, which is positioned closest to the object, has a negative optical power.

[0284] The optical system 1 of this embodiment, which has this structure, can significantly increase the field of view of the wide-angle side optical system.

[0285] In the optical system 1 of this embodiment, the front lens group GF preferably includes three or more lens components. Furthermore, a lens component refers to a single lens or a combined lens.

[0286] With this structure, the optical system 1 of this embodiment can be configured in a small size.

[0287] In the optical system 1 of this embodiment, preferably at least one of the first rear lens group GR1 and the second rear lens group GR2 has: a second optical path branching member having a second branching surface that reflects a portion of the incident light and transmits at least a portion of the incident light that is different from the first portion; a third rear lens group that allows at least a portion of the light reflected from the second branching surface to be incident; and a fourth rear lens group that allows at least a portion of the light transmitted from the second branching surface to be incident.

[0288] The optical system 1 of this embodiment, which has this structure, is capable of imaging multiple images through the first optical system OS1 or the second optical system OS2.

[0289] In the optical system 1 of this embodiment, it is preferable that the lens group having the second optical path branching member, the third optical path lens group and the fourth optical path lens group in the first rear lens group GR1 and the second rear lens group GR2 has an intermediate lens group between the optical path branching member OB and the second optical path branching member, and the intermediate lens group has positive optical power.

[0290] The optical system 1 of this embodiment with this structure can reduce the number of lens components of the rear lens group having the intermediate lens group in the first rear lens group GR1 and the second rear lens group GR2, and is constructed in a small manner.

[0291] In the optical system 1 of this embodiment, it is preferable that the image plane of the first optical system OS1 and the image plane of the second optical system OS2 are arranged on the same plane.

[0292] The optical system 1 of this embodiment, having this structure, can receive the image obtained by the first optical system OS1 and the image obtained by the second optical system OS2 through a light-receiving part disposed on the image plane, thus enabling miniaturization of the optical device equipped with the optical system. In addition, in the optical device equipped with the optical system having this structure, it is easy to make the timing of the two images consistent.

[0293] In an optical system 1 where the image planes of the first optical system OS1 and the second optical system OS2 are arranged on the same plane, it is preferable that the total focal length of the first optical system OS1 is longer than that of the second optical system OS2.

[0294] The optical system 1 of this embodiment, which has this structure, can shorten the distance from the lens surface closest to the object to the image plane.

[0295] In an optical system 1 where the image planes of the first optical system OS1 and the second optical system OS2 are arranged on the same plane, preferably, the first optical system OS1 also has a first optical path changing component and a second optical path changing component between the optical path branching component OB and the image plane. The first optical path changing component changes the optical path of the light reflected from the branching surface BP1 to be parallel to the optical path of the light transmitted through the branching surface BP1. The second optical path changing component changes the optical path of the light reflected from the branching surface BP1 after being changed by the first optical path changing component to shorten the interval between the optical path of the light transmitted through the branching surface BP1 and the optical path of the light reflected through the branching surface BP1.

[0296] The optical system 1 of this embodiment, which has this structure, can image two images close together, and thus can be configured as an optical device that receives each image through a light-receiving part.

[0297] With the above structure, an optical system can be realized that branches the incident light and images them appropriately.

[0298] The optical device of this embodiment has an optical system with the structure described above. Therefore, it is possible to branch the incident light and acquire image data corresponding to each light beam.

[0299] The optical device of this embodiment preferably has a driving unit that changes the orientation of the optical system based on image information representing the image of the optical system with the shorter overall focal length in the first optical system OS1 and the second optical system OS2.

[0300] By having this structure, the optical device of this embodiment can appropriately change the orientation of the optical system based on the wide range of conditions represented by the image obtained by the wide-angle side optical system.

[0301] In the optical device of this embodiment with a drive unit, it is preferable that the drive unit changes the orientation of the optical system so that the object detected from the image information enters the field of view of the optical system with the longer overall focal length in the first optical system OS1 and the second optical system OS2.

[0302] The optical device of this embodiment, by having this structure, can change the orientation of the optical system so that the image obtained by the telephoto side optical system represents objects contained in a large area represented by the image obtained by the wide-angle side optical system.

[0303] The optical device of this embodiment preferably has a combining unit that combines first image information and second image information. The first image information is an image information that is magnified from a portion of the image of the optical system with the shorter overall focal length in the first optical system OS1 and the second optical system OS2. The second image information is image information representing at least a portion of the image of the optical system with the longer overall focal length in the first optical system OS1 and the second optical system OS2.

[0304] According to the optical device of this embodiment having this structure, it is possible to compare the portion contained in the image obtained by the wide-angle side optical system and the image contained in the image obtained by the telephoto side optical system.

[0305] The manufacturing method of the optical system in this embodiment is a method for manufacturing an optical system having a branch surface BP1 and imaging a first light and a second light respectively. The branch surface BP1 transmits a portion of the incident light and reflects at least a portion of the incident light that is different from that portion. The first light is at least a portion of the light reflected by the branch surface BP1, and the second light is at least a portion of the light transmitted by the branch surface BP1. The manufacturing method includes: arranging a first optical system OS1 in a manner that, starting from the object side, it sequentially includes a front lens group GF having negative optical power, a light path branching member OB having the branch surface BP1, and a first rear lens group GR1 for the first light to be incident; arranging a second optical system OS2 in a manner that, starting from the object side, it sequentially includes a front lens group GF, a light path branching member OB, and a second rear lens group GR2 for the second light to be incident; and configuring the second optical system OS2 to have an overall focal length different from that of the first optical system OS1.

[0306] This method of manufacturing optical systems enables the creation of optical systems that can branch incident light and image it appropriately.

[0307] (Numerical Example)

[0308] The embodiments of this application will now be described with reference to the accompanying drawings.

[0309] (First embodiment)

[0310] In the optical system 1 of the first embodiment, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 is a wide-angle side optical system, and the second optical system OS2 is a telephoto side optical system.

[0311] Figure 2 This is a cross-sectional view of the first optical system OS1 of the optical system 1 of the first embodiment.

[0312] The first optical system OS1 of this embodiment includes, starting from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a meniscus-shaped negative lens L2 with its convex surface facing the object side, an optical path branching component OB, an aperture stop ST1, a biconvex positive lens L11, a meniscus-shaped negative lens L12 with its convex surface facing the object side, a combined negative lens of a biconvex positive lens L13 and a biconcave negative lens L14, and a biconvex positive lens L15.

[0313] A first imaging element (not shown) composed of a CCD or CMOS sensor is disposed on the image plane I1.

[0314] In the first optical system OS1 of this embodiment, lens L1 and negative lens L2 are included in the front lens group GF.

[0315] In the first optical system OS1 of this embodiment, the positive lens L11, the negative lens L12, the combined negative lens of the positive lens L13 and the negative lens L14, and the positive lens L15 are included in the first rear lens group GR1.

[0316] The values ​​of each element of the first optical system OS1 in this embodiment are recorded in Table 1-1 below.

[0317] In Table 1-1, under [Overall Elements], fA represents the total focal length of the first optical system OS1, TLA represents the total optical length of the first optical system OS1, FnoA represents the F-number of the first optical system OS1, YmaxA represents the maximum image height, ωA represents the half field of view (degrees), and Wi represents the reflectivity of the branch plane BP1. Furthermore, the values ​​listed in [Overall Elements] are for the d-line (wavelength 587.6 nm).

[0318] In Table 1-1, under [Lens Elements], m represents the order of the optical surfaces counting from the object side, r represents the radius of curvature, d represents the interplanar spacing, n(d) represents the refractive index for the d-line, and νd represents the Abbe number for the d-line. A radius of curvature r = ∞ indicates a plane. Additionally, in [Lens Elements], optical surfaces marked with "*" are aspherical.

[0319] In Table 1-1, [Focal Length Data for Each Group],

[0320] The focal length, radius of curvature, and other lengths listed in Table 1-1 are in mm. However, optical systems can achieve equivalent optical performance even when scaled up or down, so this is not a limitation.

[0321] The symbols in Table 1-1 described above are also used in the same way in the tables of the second optical system OS2 in this embodiment and in the various tables of the embodiments described later.

[0322] (Table 1-1)

[0323]

[0324]

[0325]

[0326] Figure 3 The image shows the aberrations of the first optical system OS1 in the first embodiment.

[0327] In each aberration diagram, the spherical aberration diagram represents the proportion relative to the maximum aperture, the astigmatic field curves and distortion diagram represent the value of the half-field angle, and the coma diagram represents the proportion relative to the maximum image height. Each aberration diagram represents the values ​​of the d-line and g-line (wavelength 435.8 nm). In the astigmatic diagram, S represents the sagittal image plane, and T (tangental) represents the meridional image plane. The same reference numerals as those in this embodiment are used in the aberration diagrams of other embodiments described later.

[0328] As can be seen from the aberration diagrams, the first optical system OS1 in this embodiment appropriately corrects each aberration and has high optical performance.

[0329] Figure 4 This is a cross-sectional view of the second optical system OS2 of the optical system 1 in the first embodiment.

[0330] The second optical system OS2 of this embodiment includes, starting from the object side, a negative lens L1 with a convex surface facing the object side and a meniscus-shaped negative lens L2 with a convex surface facing the object side, an optical path branching component OB, a biconvex positive lens L21, an aperture stop ST2, a combined positive lens of a biconvex positive lens L22 and a meniscus-shaped negative lens L23 with a concave surface facing the object side, a combined negative lens of a biconvex positive lens L24 and a biconcave negative lens L25, a combined negative lens of a meniscus-shaped negative lens L26 with a convex surface facing the object side and a biconvex positive lens L27, and a meniscus-shaped positive lens L28 with a concave surface facing the object side.

[0331] The image sensor I2 is equipped with a camera element consisting of a CCD or CMOS sensor.

[0332] In the second optical system OS2 of this embodiment, negative lenses L1 and L2 are included in the front lens group GF. The front lens group GF is shared with the first optical system OS1, and the same applies in the embodiments described later.

[0333] exist Figure 4 In the middle, the front lens group GF is compared to Figure 2 The smaller aperture of the front lens group GF is indicated in the cross-sectional view of the second optical system OS2 in the embodiments described later.

[0334] In the second optical system OS2 of this embodiment, the positive lens L21, the aperture stop ST2, the positive lens combining the positive lens L22 and the negative lens L23, the negative lens combining the positive lens L24 and the negative lens L25, the negative lens combining the negative lens L26 and the positive lens L27, and the positive lens L28 are included in the second rear lens group GR2.

[0335] The values ​​of each element of the second optical system OS2 in this embodiment are recorded in Tables 1-2 below.

[0336] In Table 1-2, under [Overall Elements], fB represents the total focal length of the second optical system OS2, TLB represents the total optical length of the second optical system OS2, FnoB represents the F-number of the second optical system OS2, YmaxB represents the maximum image height, and ωB represents the half field of view (degrees). Furthermore, the values ​​listed under [Overall Elements] are values ​​with respect to the d-line.

[0337] The symbols in Tables 1-2 described above are also used in the tables of the second optical system OS2 in the embodiments described later.

[0338] (Table 1-2)

[0339]

[0340]

[0341]

[0342] Figure 5 The aberration diagrams are of the second optical system OS2, which is provided by the optical system 1 of the first embodiment.

[0343] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0344] (Second Embodiment)

[0345] In the optical system 1 of the second embodiment, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 is a wide-angle side optical system, and the second optical system OS2 is a telephoto side optical system.

[0346] Figure 6 This is a cross-sectional view of the first optical system OS1 of the optical system 1 in the second embodiment.

[0347] The first optical system OS1 of this embodiment includes, starting from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a meniscus-shaped negative lens L2 with its convex surface facing the object side, a biconcave negative lens L3, an optical path branching component OB, an aperture stop ST1, a biconvex positive lens L11, a meniscus-shaped negative lens L12 with its convex surface facing the object side, a combined positive lens of the biconvex positive lens L13 and the biconcave negative lens L14, and a biconvex positive lens L15.

[0348] A first imaging element (not shown) composed of a CCD or CMOS sensor is disposed on the image plane I1.

[0349] In the first optical system OS1 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0350] In the first optical system OS1 of this embodiment, the positive lens L11, the negative lens L12, the positive lens L13 and the negative lens L14 combined positive lens, and the positive lens L15 are included in the first rear lens group GR1.

[0351] The values ​​of each element of the first optical system OS1 in this embodiment are recorded in Table 2-1 below.

[0352] In Table 2-1 [Aspherical Data], m represents the optical surface corresponding to the aspherical data, K represents the conic constant, and A4~A10 represent the aspherical coefficients.

[0353] For an aspherical surface, when the height in the direction perpendicular to the optical axis is set as y, the distance along the optical axis from the tangent plane of each aspherical surface at height y to each aspherical surface (sagittal distance) is set as S(y), the radius of curvature of the reference sphere (paraxial radius of curvature) is set as r, the conic constant is set as K, and the aspherical coefficient of order n is set as An, the aspherical surface is represented by the following equation (a). Furthermore, in each embodiment, the aspherical coefficient of order 2, A2, is 0. Additionally, "En" indicates "×10". -n ".

[0354]

[0355] The symbols in Table 2-1 described above are also used in the same way in the table of the second optical system OS2 in this embodiment and in the respective tables of the embodiments described later.

[0356] (Table 2-1)

[0357]

[0358]

[0359]

[0360]

[0361] Figure 7 The aberration diagrams are of the first optical system OS1 in the optical system 1 of the second embodiment.

[0362] As can be seen from the aberration diagrams, the first optical system OS1 in this embodiment appropriately corrects each aberration and has high optical performance.

[0363] Figure 8 This is a cross-sectional view of the second optical system OS2 of the optical system 1 in the second embodiment.

[0364] The second optical system OS2 of this embodiment, starting from the object side, sequentially includes a negative lens L1 with a convex surface facing the object side, a negative lens L2 with a convex surface facing the object side, a biconcave negative lens L3, an optical path branching component OB, a biconvex positive lens L21, an aperture stop ST2, a negative lens L22 with a convex surface facing the object side, a combined positive lens of a biconvex positive lens L23 and a negative lens L24 with a concave surface facing the object side, a combined negative lens of a biconcave negative lens L25 and a biconvex positive lens L26, and a combined positive lens of a negative lens L27 with a convex surface facing the object side and a biconvex positive lens L28.

[0365] The image sensor I2 is equipped with a camera element consisting of a CCD or CMOS sensor.

[0366] In the second optical system OS2 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0367] In the second optical system OS2 of this embodiment, the positive lens L21, the aperture stop ST2, the negative lens L22, the positive lens combining the positive lens L23 and the negative lens L24, the negative lens combining the negative lens L25 and the positive lens L26, and the positive lens combining the negative lens L27 and the positive lens L28 are included in the second rear lens group GR2.

[0368] The values ​​of each element of the second optical system OS2 in this embodiment are recorded in Table 2-2 below.

[0369] (Table 2-2)

[0370]

[0371]

[0372]

[0373]

[0374] Figure 9 The aberration diagrams are of the second optical system OS2 of the optical system 1 in the second embodiment.

[0375] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0376] (Third embodiment)

[0377] In the optical system 1 of the third embodiment, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 is a wide-angle side optical system, and the second optical system OS2 is a telephoto side optical system.

[0378] Figure 10 This is a cross-sectional view of the first optical system OS1 of the optical system 1 in the third embodiment.

[0379] The first optical system OS1 of this embodiment includes, starting from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave negative lens L2, an optical path branching component OB, an aperture stop ST1, a meniscus-shaped positive lens L11 with its concave surface facing the object side, a combined positive lens of a biconvex positive lens L12 and a biconcave negative lens L13, and a meniscus-shaped positive lens L14 with its convex surface facing the object side.

[0380] A first imaging element (not shown) composed of a CCD or CMOS sensor is disposed on the image plane I1.

[0381] In the first optical system OS1 of this embodiment, negative lens L1 and negative lens L2 are included in the front lens group GF.

[0382] In the first optical system OS2 of this embodiment, the positive lens L11, the negative lens L12, the positive lens L13 and the negative lens L14 combined positive lens, and the positive lens L15 are included in the first rear lens group GR1.

[0383] The values ​​of each element of the first optical system OS1 in this embodiment are recorded in Table 3-1 below.

[0384] (Table 3-1)

[0385]

[0386]

[0387]

[0388]

[0389] Figure 11 The aberration diagrams are of the first optical system OS1 in the optical system 1 of the third embodiment.

[0390] As can be seen from the aberration diagrams, the first optical system OS1 in this embodiment appropriately corrects each aberration and has high optical performance.

[0391] Figure 12 This is a cross-sectional view of the second optical system OS2 of the optical system 1 in the third embodiment.

[0392] The second optical system OS2 of this embodiment includes, starting from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave negative lens L2, an optical path branching component OB, a meniscus-shaped positive lens L21 with its concave surface facing the object side, an aperture stop ST2, a meniscus-shaped negative lens L22 with its convex surface facing the object side, a combined positive lens of a biconvex positive lens L23 and a meniscus-shaped negative lens L24 with its concave surface facing the object side, a combined negative lens of a biconcave negative lens L25 and a biconvex positive lens L26, and a combined positive lens of a meniscus-shaped negative lens L27 with its convex surface facing the object side and a biconvex positive lens L28.

[0393] The image sensor I2 is equipped with a camera element consisting of a CCD or CMOS sensor.

[0394] In the second optical system OS2 of this embodiment, negative lens L1 and negative lens L2 are included in the front lens group GF.

[0395] In the second optical system OS2 of this embodiment, the positive lens L21, the aperture stop ST2, the negative lens L22, the positive lens combining the positive lens L23 and the negative lens L24, the negative lens combining the negative lens L25 and the positive lens L26, and the positive lens combining the negative lens L27 and the positive lens L28 are included in the second rear lens group GR2.

[0396] The values ​​of each element of the second optical system OS2 in this embodiment are recorded in Table 3-2 below.

[0397] (Table 3-2)

[0398]

[0399]

[0400]

[0401] Figure 13 The aberration diagrams are of the second optical system OS2, which is included in the optical system 1 of the third embodiment.

[0402] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0403] (4th embodiment)

[0404] In the optical system 1 of the fourth embodiment, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 is a wide-angle side optical system, and the second optical system OS2 is a telephoto side optical system.

[0405] Figure 14 This is a cross-sectional view of the first optical system OS1 of the optical system 1 in the fourth embodiment.

[0406] The first optical system OS1 of this embodiment includes, starting from the object side, a negative lens L1 with a meniscus shape and convex surface facing the object side, a biconcave negative lens L2, a positive lens L3 with a meniscus shape and concave surface facing the object side, an optical path branching component OB, a positive lens L11 with a meniscus shape and convex surface facing the object side, an aperture stop ST1, a negative lens L12 with a meniscus shape and convex surface facing the object side, a positive lens combining a biconvex positive lens L13 and a biconcave negative lens L14, a negative lens L15 with a meniscus shape and convex surface facing the object side, and a positive lens L16 with a meniscus shape and convex surface facing the object side.

[0407] A first imaging element (not shown) composed of a CCD or CMOS sensor is disposed on the image plane I1.

[0408] In the first optical system OS1 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0409] In the first optical system OS2 of this embodiment, the positive lens L11, the aperture stop ST1, the negative lens L12, the positive lens L13 and the negative lens L14 combined positive lens, the negative lens L15, and the positive lens L16 are included in the first rear lens group GR1.

[0410] The values ​​of each element of the first optical system OS1 in this embodiment are recorded in Table 4-1 below.

[0411] (Table 4-1)

[0412]

[0413]

[0414]

[0415] Figure 15 The aberration diagrams are of the first optical system OS1 in the optical system 1 of the fourth embodiment.

[0416] As can be seen from the aberration diagrams, the first optical system OS1 in this embodiment appropriately corrects each aberration and has high optical performance.

[0417] Figure 16 This is a cross-sectional view of the second optical system OS2 of the optical system 1 in the fourth embodiment.

[0418] The second optical system OS2 of this embodiment includes, starting from the object side, a negative lens L1 with a meniscus shape and convex surface facing the object side, a biconcave negative lens L2, a positive lens L3 with a meniscus shape and concave surface facing the object side, an optical path branching component OB, a biconvex positive lens L21, an aperture stop ST2, a negative lens L22 with a meniscus shape and convex surface facing the object side, a combined negative lens of a biconvex positive lens L23 and a biconcave negative lens L24, a biconvex positive lens L25, a negative lens L26 with a meniscus shape and convex surface facing the object side, and a positive lens L27 with a meniscus shape and concave surface facing the object side.

[0419] The image sensor I2 is equipped with a camera element consisting of a CCD or CMOS sensor.

[0420] In the second optical system OS2 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0421] In the second optical system OS2 of this embodiment, the positive lens L21, the aperture stop ST2, the negative lens L22, the combined negative lens of the positive lens L23 and the negative lens L24, the positive lens L25, the negative lens L26, and the positive lens L27 are included in the second rear lens group GR2.

[0422] The values ​​of each element of the second optical system OS2 in this embodiment are recorded in Table 4-2 below.

[0423] (Table 4-2)

[0424]

[0425]

[0426]

[0427] Figure 17 The aberration diagrams are of the second optical system OS2, which is present in the optical system 1 of the fourth embodiment.

[0428] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0429] (5th embodiment)

[0430] In the optical system 1 of the fifth embodiment, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 is a wide-angle side optical system, and the second optical system OS2 is a telephoto side optical system.

[0431] Figure 18 This is a cross-sectional view of the first optical system OS1 of the optical system 1 in the fifth embodiment.

[0432] The first optical system OS1 of this embodiment includes, starting from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave negative lens L2, a meniscus-shaped positive lens L3 with its convex surface facing the object side, an optical path branching component OB, a biconvex positive lens L11, an aperture stop ST1, a combined negative lens of the biconvex positive lens L12 and the biconcave negative lens L13, a biconvex positive lens L14, and a meniscus-shaped positive lens L15 with its convex surface facing the object side.

[0433] A first imaging element (not shown) composed of a CCD or CMOS sensor is disposed on the image plane I1.

[0434] In the first optical system OS1 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0435] In the first optical system OS2 of this embodiment, the positive lens L11, the aperture stop ST1, the combined negative lens of the positive lens L12 and the negative lens L13, the positive lens L14, and the positive lens L15 are included in the first rear lens group GR1.

[0436] The values ​​of each element of the first optical system OS1 in this embodiment are recorded in Table 5-1 below.

[0437] (Table 5-1)

[0438]

[0439]

[0440]

[0441]

[0442] Figure 19The aberration diagrams are of the first optical system OS1 in the optical system 1 of the fifth embodiment.

[0443] As can be seen from the aberration diagrams, the first optical system OS1 in this embodiment appropriately corrects each aberration and has high optical performance.

[0444] Figure 20 This is a cross-sectional view of the second optical system OS2 of the optical system 1 in the fifth embodiment.

[0445] The second optical system OS2 of this embodiment includes, starting from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave negative lens L2, a meniscus-shaped positive lens L3 with its convex surface facing the object side, an optical path branching component OB, a biconvex positive lens L21, an aperture stop ST2, a meniscus-shaped negative lens L22 with its convex surface facing the object side, a combined negative lens of the biconvex positive lens L23 and the biconcave negative lens L24, a biconvex positive lens L25, a meniscus-shaped negative lens L26 with its convex surface facing the object side, and a biconvex positive lens L27.

[0446] The image sensor I2 is equipped with a camera element consisting of a CCD or CMOS sensor.

[0447] In the second optical system OS2 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0448] In the second optical system OS2 of this embodiment, the positive lens L21, the aperture stop ST2, the negative lens L22, the combined negative lens of the positive lens L23 and the negative lens L24, the positive lens L25, the negative lens L26, and the positive lens L27 are included in the second rear lens group GR2.

[0449] The values ​​of each element of the second optical system OS2 in this embodiment are recorded in Table 5-2 below.

[0450] (Table 5-2)

[0451]

[0452]

[0453]

[0454]

[0455] Figure 21 The aberration diagrams are of the second optical system OS2, which is included in the optical system 1 of the fifth embodiment.

[0456] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0457] (Sixth embodiment)

[0458] In the optical system 1 of the sixth embodiment, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 is a wide-angle side optical system, and the second optical system OS2 is a telephoto side optical system.

[0459] Figure 22 This is a cross-sectional view of the first optical system OS1 of the optical system 1 in the sixth embodiment.

[0460] In this embodiment, the first optical system OS1, starting from the object side, sequentially includes a negative lens L1 with a meniscus shape and convex surface facing the object side, a biconcave negative lens L2, a positive lens L3 with a meniscus shape and concave surface facing the object side, an optical path branching component OB, a biconvex positive lens L11, an aperture stop ST1, a negative lens L12 with a meniscus shape and convex surface facing the object side, a positive lens combining the biconvex positive lens L13 and the biconcave negative lens L14, a biconvex positive lens L15, and a negative lens L16 with a meniscus shape and convex surface facing the object side.

[0461] A first imaging element (not shown) composed of a CCD or CMOS sensor is disposed on the image plane I1.

[0462] In the first optical system OS1 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0463] In the first optical system OS1 of this embodiment, the positive lens L11, the aperture stop ST1, the positive lens L12, the positive lens L13 and the negative lens L14 combined positive lens, the positive lens L15 and the negative lens L16 are included in the first rear lens group GR1.

[0464] The values ​​of each element of the first optical system OS1 in this embodiment are recorded in Table 6-1 below.

[0465] (Table 6-1)

[0466]

[0467]

[0468]

[0469]

[0470] Figure 23 The aberration diagrams are of the first optical system OS1 in the optical system 1 of the sixth embodiment.

[0471] As can be seen from the aberration diagrams, the first optical system OS1 in this embodiment appropriately corrects each aberration and has high optical performance.

[0472] Figure 24 This is a cross-sectional view of the second optical system OS2 of the optical system 1 in the sixth embodiment.

[0473] The second optical system OS2 of this embodiment includes, starting from the object side, a negative lens L1 with a convex surface facing the object side and having a meniscus shape, a biconcave negative lens L2, a positive lens L3 with a concave surface facing the object side and having a meniscus shape, an optical path branching component OB, a biconvex positive lens L21, an aperture stop ST2, a negative lens L22 with a convex surface facing the object side and having a meniscus shape, a positive lens combining a biconvex positive lens L23 and a biconcave negative lens L24, a biconvex positive lens L25, and a negative lens L26 with a concave surface facing the object side.

[0474] The image sensor I2 is equipped with a camera element consisting of a CCD or CMOS sensor.

[0475] In the second optical system OS2 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0476] In the second optical system OS2 of this embodiment, the positive lens L21, the aperture stop ST2, the negative lens L22, the positive lens L23 and the negative lens L24 combined positive lens, the positive lens L25, and the negative lens L26 are included in the second rear lens group GR2.

[0477] The values ​​of each element of the second optical system OS2 in this embodiment are recorded in Table 6-2 below.

[0478] (Table 6-2)

[0479]

[0480]

[0481]

[0482]

[0483] Figure 25 The aberration diagrams are of the second optical system OS2, which is present in the optical system 1 of the sixth embodiment.

[0484] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0485] (Seventh embodiment)

[0486] Figure 26 This is a schematic diagram illustrating the overall structure of the optical system 1 in the seventh embodiment.

[0487] In the optical system 1 of this embodiment, the first optical system OS1 has a longer overall system focal length than the second optical system OS2. That is, the first optical system OS1 is a telephoto-side optical system, and the second optical system OS2 is a wide-angle-side optical system.

[0488] In this embodiment, the image plane I1 of the first optical system OS1 and the image plane I2 of the second optical system OS2 are arranged on the same plane.

[0489] The first optical system OS1 of this embodiment has a first optical path changing component between the optical path branching component OB and the image plane I1. The first optical path changing component changes the optical path of the light reflected from the branching surface BP1 to be parallel to the optical path of the light transmitted through the branching surface BP1.

[0490] In this embodiment, the first optical path changing component is composed of a right-angle prism RAP1, which has a reflective surface that changes the incident light into an optical path parallel to the light transmitted through the branching surface BP1. The first optical path changing component may also be composed of a reflective mirror, which has a reflective surface that changes the incident light into an optical path parallel to the light transmitted through the branching surface BP1.

[0491] The first optical system OS1 of this embodiment has a second optical path changing component between the first optical path changing component and the image plane. The second optical path changing component changes the optical path of the light reflected from the branch plane BP1 after being changed by the first optical path changing component, so as to shorten the interval between the optical path of the light transmitted through the branch plane BP1 and the optical path of the light.

[0492] In this embodiment, the second optical path alteration component comprises right-angle prism RAP2 and right-angle prism RAP3. Right-angle prism RAP2 has a reflective surface that directs the incident light towards a direction close to the optical path of the light transmitted through the branching surface BP1. Right-angle prism RAP3 alters the incident light to be parallel to the optical path of the light transmitted through the branching surface BP1 and directs it towards the image plane I1. At least one of right-angle prisms RAP2 and RAP3 may also be composed of a mirror.

[0493] Figure 27 This is a cross-sectional view of the first optical system OS1 of the optical system 1 in the seventh embodiment.

[0494] The first optical system OS1 of this embodiment includes, starting from the object side, a negative lens L1 with a convex surface facing the object side and having a meniscus shape, a biconcave negative lens L2, a positive lens L3 with a concave surface facing the object side and having a meniscus shape, an optical path branching component OB, a right-angle prism RAP1, a biconvex positive lens L11, an aperture stop ST1, a negative lens L12 with a convex surface facing the object side and having a meniscus shape, a positive lens combining a biconvex positive lens L13 and a biconcave negative lens L14, a biconvex positive lens L15, a negative lens L16 with a concave surface facing the object side and having a meniscus shape, a right-angle prism RAP2, and a right-angle prism RAP3.

[0495] The image plane I1 is equipped with an imaging element composed of CCD or CMOS, etc.

[0496] In the first optical system OS1 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0497] In the first optical system OS1 of this embodiment, the positive lens L11, the aperture stop ST1, the negative lens L12, the positive lens L13 and the negative lens L14 combined positive lens, the positive lens L15 and the negative lens L16 are included in the first rear lens group GR1.

[0498] The values ​​of each element of the first optical system OS1 in this embodiment are recorded in Table 7-1 below.

[0499] (Table 7-1)

[0500]

[0501]

[0502]

[0503]

[0504] Figure 28 The aberration diagrams are of the first optical system OS1 in the optical system 1 of the seventh embodiment.

[0505] As can be seen from the aberration diagrams, the first optical system OS1 in this embodiment appropriately corrects each aberration and has high optical performance.

[0506] Figure 29 This is a cross-sectional view of the second optical system OS2 of the optical system 1 in the seventh embodiment.

[0507] The second optical system OS2 of this embodiment includes, starting from the object side, a negative lens L1 with a convex surface facing the object side and having a meniscus shape, a biconcave negative lens L2, a positive lens L3 with a concave surface facing the object side and having a meniscus shape, an optical path branching component OB, a positive lens L21 with a convex surface facing the object side and having a meniscus shape, an aperture stop ST2, a negative lens L22 with a convex surface facing the object side and having a meniscus shape, a positive lens combining a biconvex positive lens L23 and a biconcave negative lens L24, a biconvex positive lens L25, and a negative lens L26 with a convex surface facing the object side and having a meniscus shape.

[0508] A first imaging element (not shown) composed of a CCD or CMOS sensor is disposed on the image plane I2.

[0509] In the second optical system OS2 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0510] In the second optical system OS2 of this embodiment, the positive lens L21, the aperture stop ST1, the negative lens L22, the positive lens L23 and the negative lens L24 combined positive lens, the positive lens L25 and the negative lens L26 are included in the second rear lens group GR2.

[0511] The values ​​of each element of the second optical system OS2 in this embodiment are recorded in Table 7-2 below.

[0512] (Table 7-2)

[0513]

[0514]

[0515]

[0516]

[0517] Figure 30 The aberration diagrams are of the second optical system OS2, which is included in the optical system 1 of the seventh embodiment.

[0518] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0519] (Embodiment 8)

[0520] Figure 31 This is a schematic diagram illustrating the overall structure of the optical system in the 8th embodiment.

[0521] In this embodiment, the light incident on the front lens group GF is divided into reflected light and transmitted light by the branching surface BP1 of the optical path branching component OB.

[0522] Light reflected from branching surface BP1 is incident on optical path branching component OBx, which has branching surface BPx. At branching surface BPx, light further branches into reflected light and transmitted light. Branching surface BPx transmits a portion of the incident light and reflects at least a portion of the incident light that is different from that portion. Optical path branching component OBx is a cubic beam splitter (prism) with branching surface BPx. Optical path branching component OBx can also be a planar beam splitter (half-reflector) with branching surface BPx.

[0523] The light transmitted through the branch plane BPx (optical axis AXa) is incident on the lens group Ga and imaged on the image plane Ia. Conversely, the light reflected from the branch plane BPx (optical axis AXb) is incident on the lens group Gb and imaged on the image plane Ib.

[0524] The light transmitted through the branching surface BP1 is incident on the optical path branching component OBy, which has a branching surface BPy, via the intermediate lens group GM. At the branching surface BPy, the light further branches into reflected light and transmitted light. The branching surface BPy transmits a portion of the incident light and reflects at least a portion of the incident light that is different from that portion. The optical path branching component OBy is a cubic beam splitter (prism) with a branching surface BPy. The optical path branching component OBy can also be a planar beam splitter (half-reflector) with a branching surface BPy.

[0525] The light reflected from the branch plane BPy (optical axis AXc) is incident on lens group Gc and imaged on image plane Ic. Conversely, the light transmitted from the branch plane BPy (optical axis AXd) is incident on lens group Gd and imaged on image plane Id.

[0526] In the optical system of the eighth embodiment, a first rear-side lens group GR1, into which a first light (optical axes AXa, AXb) is incident, includes a light path branching member OBx, a lens group Ga, and a lens group Gb, wherein the first light is at least a portion of the light reflected from the branching surface BP. The light path branching member OBx is an example of a second light path branching member having a second branching surface that reflects a portion of the incident light and transmits at least a portion of the incident light that is different from that portion. The lens group Gb is an example of a third rear-side lens group into which at least a portion (optical axis AXb) of the light reflected from the second branching surface is incident. The lens group Ga is an example of a fourth rear-side lens group into which at least a portion (optical axis AXa) of the light transmitted from the second branching surface is incident.

[0527] In the optical system of the eighth embodiment, the second rear-side lens group GR2, into which the second light (optical axes AXc, AXd) is incident, includes an intermediate lens group GM, a light path branching component OBy, a lens group Gc, and a lens group Gd, wherein the second light is at least a portion of the light transmitted at the branching surface BP. The light path branching component OBy is another example of a second light path branching component having a second branching surface that reflects a portion of the incident light and transmits at least a portion of the incident light that is different from that portion. The lens group Gc is another example of a third rear-side lens group into which at least a portion (optical axis AXc) of the light reflected at the second branching surface is incident. The lens group Gd is another example of a fourth rear-side lens group into which at least a portion (optical axis AXd) of the light transmitted at the second branching surface is incident.

[0528] An optical system having optical system OSa as the first optical system OS1 and optical system OSd as the second optical system OS2 is referred to as the optical system of embodiment 8-1. Optical system OSa includes a front lens group GF, a light path branching component OB, a light path branching component OBx, and a lens group Ga. Optical system OSd includes a front lens group GF, a light path branching component OB, an intermediate lens group GM, a light path branching component OBy, and a lens group Gd. In the optical system of embodiment 8-1, lens group Ga belongs to the first rear lens group GR1, and the intermediate lens group GM, the light path branching component OBy, and the lens group Gd belong to the second rear lens group GR2. In the optical system of embodiment 8-1, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 is a wide-angle side optical system, and the second optical system OS2 is a telephoto side optical system.

[0529] An optical system having an optical system OSb as the first optical system OS1 and an optical system OSc as the second optical system OS2 is referred to as the optical system of the 8-2 embodiment. The optical system OSb includes a front lens group GF, a light path branching component OB, a light path branching component OBx, and a lens group Gb. The optical system OSc includes a front lens group GF, a light path branching component OB, an intermediate lens group GM, a light path branching component OBy, and a lens group Gc. In the optical system of the 8-2 embodiment, lens group Gb belongs to the first rear lens group GR1, and the intermediate lens group GM, the light path branching component OBy, and lens group Gc belong to the second rear lens group GR2. In the optical system of the 8-2 embodiment, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 is a wide-angle side optical system, and the second optical system OS2 is a telephoto side optical system.

[0530] (Example 8-1)

[0531] Figure 32 This is a cross-sectional view of the first optical system OS1 of the optical system of embodiment 8-1.

[0532] The first optical system OS1 of this embodiment includes, starting from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave negative lens L2, a biconcave negative lens L3, an optical path branching component OB, an optical path branching component OBx, an aperture stop STa, a biconvex positive lens La1, a meniscus-shaped negative lens La2 with its convex surface facing the object side, a combined positive lens of the biconvex positive lens La3 and the biconcave negative lens La4, and a biconvex positive lens La5.

[0533] A first imaging element (not shown) composed of a CCD or CMOS sensor is disposed on the image plane Ia.

[0534] In the first optical system OS1 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0535] In the first optical system OS1 of this embodiment, the positive lens La1, the negative lens La2, the positive lens La3 and the negative lens La4 combined positive lens, and the positive lens La5 are included in the first rear lens group GR1.

[0536] The values ​​of each element of the first optical system OS1 in this embodiment are recorded in Table 8-1-1 below.

[0537] (Table 8-1-1)

[0538]

[0539]

[0540]

[0541]

[0542] Figure 33 The aberration diagrams are for the first optical system OS1 of the optical system of the 8-1 embodiment.

[0543] As can be seen from the aberration diagrams, the first optical system OS1 in this embodiment appropriately corrects each aberration and has high optical performance.

[0544] Figure 34 This is a cross-sectional view of the second optical system OS2 of the optical system in the 8-1 embodiment.

[0545] The second optical system OS2 of this embodiment, starting from the object side, sequentially includes a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave negative lens L2, a biconcave negative lens L3, an optical path branching component OB, an aperture stop STM, a biconvex positive lens LM1, a meniscus-shaped negative lens LM2 with its convex surface facing the object side, a combined positive lens of a biconvex positive lens LM3 and a meniscus-shaped negative lens LM4 with its concave surface facing the object side, an optical path branching component OBy, a combined negative lens of a meniscus-shaped negative lens Ld1 with its convex surface facing the object side and a meniscus-shaped positive lens Ld2 with its convex surface facing the object side, and a combined positive lens of a meniscus-shaped negative lens Ld3 with its convex surface facing the object side and a biconvex positive lens Ld4.

[0546] The image sensor, consisting of a CCD or CMOS sensor, is mounted on the image plane ID.

[0547] In the second optical system OS2 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0548] In the second optical system OS2 of this embodiment, the positive lens LM1, the negative lens LM2, the positive lens LM3 and the negative lens LM4 combined positive lens, the optical path branching component OBy, the negative lens Ld1 and the positive lens Ld2 combined negative lens, and the positive lens Ld3 and the positive lens Ld4 combined positive lens are included in the second rear lens group GR2.

[0549] The values ​​of each element of the second optical system OS2 of this embodiment are recorded in Table 8-1-2 below.

[0550] (Table 8-1-2)

[0551]

[0552]

[0553]

[0554]

[0555] Figure 35 The aberration diagrams are for the second optical system OS2, which is the optical system of the 8-1 embodiment.

[0556] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0557] (Example 8-2)

[0558] Figure 36This is a cross-sectional view of the first optical system OS1 of the optical system in the 8-2 embodiment.

[0559] The first optical system OS1 of this embodiment includes, starting from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave negative lens L2, a biconcave negative lens L3, an optical path branching component OB, an optical path branching component OBx, an aperture stop STb, a meniscus-shaped positive lens Lb1 with its concave surface facing the object side, a meniscus-shaped negative lens Lb2 with its convex surface facing the object side, a combined positive lens of a biconvex positive lens Lb3 and a biconcave negative lens Lb4, and a biconvex positive lens Lb5.

[0560] A first imaging element (not shown) composed of a CCD or CMOS sensor is disposed on the image plane Ib.

[0561] In the first optical system OS1 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0562] In the first optical system OS1 of this embodiment, the positive lens Lb1, the negative lens Lb2, the positive lens Lb3 and the negative lens Lb4 combined positive lens, and the positive lens Lb5 are included in the first rear lens group GR1.

[0563] The values ​​of each element of the first optical system OS1 in this embodiment are recorded in Table 8-2-1 below.

[0564] (Table 8-2-1)

[0565]

[0566]

[0567]

[0568]

[0569] Figure 37 The aberration diagrams are for the first optical system OS1 of the optical system in the 8-2 embodiment.

[0570] As can be seen from the aberration diagrams, the first optical system OS1 in this embodiment appropriately corrects each aberration and has high optical performance.

[0571] Figure 38 This is a cross-sectional view of the second optical system OS2 of the optical system in the 8-2 embodiment.

[0572] The second optical system OS2 of this embodiment, starting from the object side, sequentially includes a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave negative lens L2, a biconcave negative lens L3, an optical path branching component OB, an aperture stop STM, a biconvex positive lens LM1, a meniscus-shaped negative lens LM2 with its convex surface facing the object side, a combined positive lens of a biconvex positive lens LM3 and a meniscus-shaped negative lens LM3 with its concave surface facing the object side, an optical path branching component OBy, a combined positive lens of a meniscus-shaped negative lens Lc1 with its convex surface facing the object side and a meniscus-shaped positive lens Lc2 with its convex surface facing the object side, a biconvex positive lens Lc3, and a combined negative lens of a biconcave negative lens Lc4 and a biconvex positive lens Lc5.

[0573] The image sensor IC is equipped with a shooting element composed of CCD or CMOS.

[0574] In the second optical system OS2 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0575] In the second optical system OS2 of this embodiment, the positive lens LM1, the negative lens LM2, the positive lens LM3 and the negative lens LM4, the optical path branching component OBy, the positive lens Lc1 and the positive lens Lc2, the positive lens Lc3, and the negative lens Lc4 and the positive lens Lc5 are included in the second rear lens group GR2.

[0576] The values ​​of each element of the second optical system OS2 in this embodiment are recorded in Table 8-2-2 below.

[0577] (Table 8-2-2)

[0578]

[0579]

[0580]

[0581]

[0582] Figure 39 The aberration diagrams are for the second optical system OS2, which is the optical system of the 8-2 embodiment.

[0583] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0584] (Version 9)

[0585] The optical system in this embodiment has the same characteristics as... Figure 31 The overall structure of the optical system in the eighth embodiment shown is the same as the overall structure.

[0586] The optical system having optical system OSa as the first optical system OS1 and optical system OSd as the second optical system OS2 is referred to as the optical system of embodiment 9-1. Optical system OSa includes a front lens group GF, a light path branching component OB, a light path branching component OBx, and a lens group Ga. Optical system OSd includes a front lens group GF, a light path branching component OB, an intermediate lens group GM, a light path branching component OBy, and a lens group Gd. In the optical system of embodiment 8-1, lens group Ga belongs to the first rear lens group GR1, and the intermediate lens group GM, the light path branching component OBy, and the lens group Gd belong to the second rear lens group GR2. In the optical system of embodiment 9-1, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 is a wide-angle side optical system, and the second optical system OS2 is a telephoto side optical system.

[0587] The optical system having optical system OSb as the first optical system OS1 and optical system OSc as the second optical system OS2 is referred to as the optical system of embodiment 9-2. Optical system OSb includes a front lens group GF, a light path branching component OB, a light path branching component OBx, and a lens group Gb. Optical system OSc includes a front lens group GF, a light path branching component OB, an intermediate lens group GM, a light path branching component OBy, and a lens group Gc. In the optical system of embodiment 8-2, lens group Gb belongs to the first rear lens group GR1, and the intermediate lens group GM, the light path branching component OBy, and lens group Gc belong to the second rear lens group GR2. In the optical system of embodiment 9-2, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 belongs to the wide-angle side optical system, and the second optical system OS2 belongs to the telephoto side optical system.

[0588] The front lens group GF, optical path branching component OB, optical path branching component OBx, lens group Ga, and lens group Gb of this embodiment are the same as those of the 8th embodiment. That is, the first optical system OS1 of the 9-1 embodiment and the first optical system OS1 of the 9-2 embodiment are the same as those of the 8-1 embodiment and the 8-2 embodiment, respectively. Therefore, descriptions of the structure of these optical systems and their aberration diagrams are omitted.

[0589] (Example 9-1)

[0590] Figure 40 This is a cross-sectional view of the second optical system OS2 of the optical system in the 9-1 embodiment.

[0591] The second optical system OS2 of this embodiment, starting from the object side, sequentially includes a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave negative lens L2, a biconcave negative lens L3, an optical path branching component OB, a biconvex positive lens LM1, an aperture stop STM, a meniscus-shaped negative lens LM2 with its convex surface facing the object side, a combined positive lens of a biconvex positive lens LM3 and a meniscus-shaped negative lens LM4 with its concave surface facing the object side, an optical path branching component OBy, a combined negative lens of a biconcave negative lens Ld1 and a biconvex positive lens Ld2, and a combined positive lens of a meniscus-shaped negative lens Ld3 with its convex surface facing the object side and a biconvex positive lens Ld4.

[0592] The image sensor, consisting of a CCD or CMOS sensor, is mounted on the image plane ID.

[0593] In the second optical system OS2 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0594] In the second optical system OS2 of this embodiment, the positive lens LM1, the aperture stop STM, the negative lens LM2, the positive lens combining the positive lens LM3 and the negative lens LM4, the optical path branching component OBy, the negative lens combining the negative lens Ld1 and the positive lens Ld2, and the positive lens combining the negative lens Ld3 and the positive lens Ld4 are included in the second rear lens group GR2.

[0595] The values ​​of each element of the second optical system OS2 of this embodiment are recorded in Table 9-1-2 below.

[0596] (Table 9-1-2)

[0597]

[0598]

[0599]

[0600]

[0601] Figure 41 The aberration diagrams are for the second optical system OS2, which is the optical system of embodiment 9-1.

[0602] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0603] (Example 9-2)

[0604] Figure 42 This is a cross-sectional view of the second optical system OS2 of the optical system in the 9-2 embodiment.

[0605] The second optical system OS2 of this embodiment, starting from the object side, sequentially includes a meniscus-shaped negative lens L1 with its convex surface facing the object side, a biconcave negative lens L2, a biconcave negative lens L3, an optical path branching component OB, a biconvex positive lens LM1, an aperture stop STM, a meniscus-shaped negative lens LM2 with its convex surface facing the object side, a combined positive lens of a biconvex positive lens LM3 and a meniscus-shaped negative lens LLM4 with its concave surface facing the object side, an optical path branching component OBy, a combined positive lens of a meniscus-shaped negative lens Lc1 with its convex surface facing the object side and a biconvex positive lens Lc2, and a combined positive lens of a meniscus-shaped negative lens Lc3 with its convex surface facing the object side and a biconvex positive lens Lc4.

[0606] The image sensor IC is equipped with a shooting element composed of CCD or CMOS.

[0607] In the second optical system OS2 of this embodiment, negative lens L1, negative lens L2 and negative lens L3 are included in the front lens group GF.

[0608] In the second optical system OS2 of this embodiment, the positive lens LM1, the negative lens LM2, the positive lens LM3 and the negative lens LM4 combined positive lens, the optical path branching component OBy, the negative lens Lc1 and the positive lens Lc2 combined positive lens, and the negative lens Lc3 and the positive lens Lc4 combined positive lens are included in the second rear lens group GR2.

[0609] The values ​​of each element of the second optical system OS2 in this embodiment are recorded in Table 9-2-2 below.

[0610] (Table 9-2-2)

[0611]

[0612]

[0613]

[0614]

[0615] Figure 43 The aberration diagrams are for the second optical system OS2, which is the optical system of the 9-2 embodiment.

[0616] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0617] (10th embodiment)

[0618] In the optical system 1 of the 10th embodiment, the second optical system OS2 has a longer overall system focal length than the first optical system OS1. That is, the first optical system OS1 is a wide-angle side optical system, and the second optical system OS2 is a telephoto side optical system.

[0619] Figure 44 This is a cross-sectional view of the first optical system OS1 of the optical system 1 of the 10th embodiment.

[0620] The first optical system OS1 of this embodiment includes, starting from the object side, a negative lens L1 with a convex surface facing the object side and a meniscus shape, a negative lens L2 with a convex surface facing the object side, an optical path branching component OB, an aperture stop ST1, a positive lens L11 with a concave surface facing the object side and a meniscus shape, a negative lens L12 with a convex surface facing the object side, a positive lens combining a biconvex positive lens L13 and a biconcave negative lens L14, and a positive lens L15 with a convex surface facing the object side and a meniscus shape.

[0621] A first imaging element (not shown) composed of a CCD or CMOS sensor is disposed on the image plane I1.

[0622] In the first optical system OS1 of this embodiment, negative lens L1 and negative lens L2 are included in the front lens group GF.

[0623] In the first optical system OS1 of this embodiment, the positive lens L11, the negative lens L12, the positive lens L13 and the negative lens L14 combined positive lens, and the positive lens L15 are included in the first rear lens group GR1.

[0624] The values ​​of each element of the first optical system OS1 in this embodiment are recorded in Table 10-1 below.

[0625] (Table 10-1)

[0626]

[0627]

[0628]

[0629]

[0630] Figure 45The aberration diagrams are of the first optical system OS1 in the optical system 1 of the 10th embodiment.

[0631] As can be seen from the aberration diagrams, the first optical system OS1 in this embodiment appropriately corrects each aberration and has high optical performance.

[0632] Figure 46 This is a cross-sectional view of the second optical system OS2 of the optical system 1 in the 10th embodiment.

[0633] The second optical system OS2 of this embodiment includes, starting from the object side, a meniscus-shaped negative lens L1 with its convex surface facing the object side, a meniscus-shaped negative lens L2 with its convex surface facing the object side, an optical path branching component OB, an aperture stop ST2, a meniscus-shaped negative lens L21 with its convex surface facing the object side, a biconvex positive lens L22, a biconvex positive lens L23, and a combined negative lens of a meniscus-shaped negative lens L24 with its convex surface facing the object side and a biconvex positive lens L25.

[0634] The image sensor I2 is equipped with a camera element consisting of a CCD or CMOS sensor.

[0635] In the second optical system OS2 of this embodiment, negative lens L1 and negative lens L2 are included in the front lens group GF.

[0636] In the second optical system OS2 of this embodiment, the negative lens L21, the positive lens L22, the positive lens L23, and the combined negative lens of the negative lens L24 and the positive lens L25 are included in the second rear lens group GR2.

[0637] The values ​​of each element of the second optical system OS2 in this embodiment are recorded in Table 10-2 below.

[0638] (Table 10-2)

[0639]

[0640]

[0641]

[0642] Figure 47 The aberration diagrams are of the second optical system OS2, which is provided by the optical system 1 of the 10th embodiment.

[0643] As can be seen from the aberration diagrams, the second optical system OS2 in this embodiment appropriately corrects each aberration and has high optical performance.

[0644] According to the above embodiments, an optical system can be realized that branches the incident light and images them appropriately.

[0645] The following represent the corresponding values ​​of the conditional expressions in each embodiment.

[0646] fA is the total focal length of the wide-angle optical system, fB is the total focal length of the telephoto optical system, fF is the focal length of the front lens group GF, and f1 is the focal length of the lens in the front lens group GF positioned closest to the object. D12 is the optical axis spacing between the lens in the front lens group GF positioned closest to the object and the lens adjacent to it on the image plane side.

[0647] TLA is the total optical length of the wide-angle optical system, and TLB is the total optical length of the telephoto optical system. r11 is the radius of curvature of the object-side lens surface of the lens in the front lens group GF positioned closest to the object; r12 is the radius of curvature of the image-side lens surface of the lens in the front lens group GF positioned closest to the object; and r21 is the radius of curvature of the object-side lens surface of the lens adjacent to the image-side lens in the front lens group GF positioned closest to the object. ωA is the half-field of view of the wide-angle optical system, and ωB is the half-field of view of the telephoto optical system.

[0648] fpA is the combined focal length of the positive lens elements continuously arranged on the image plane side, starting from the positive lens element positioned closest to the object in the rear lens group of the wide-angle optical system. fpB is the combined focal length of the positive lens elements continuously arranged on the image plane side, starting from the positive lens element positioned closest to the object in the rear lens group of the telephoto optical system. fRA is the focal length of the rear lens group of the wide-angle optical system, and fRB is the focal length of the rear lens group of the telephoto optical system.

[0649] nd1 is the refractive index of the lens in the front lens group GF positioned closest to the object side, with respect to the d-line. nd2 is the refractive index of the lenses in the front lens group GF adjacent to the lens positioned closest to the object side, positioned on the image plane side, positioned with respect to the d-line. ndaveF is the average refractive index of the lenses in the front lens group GF positioned with respect to the d-line. Wi is the reflectivity or transmittance of the optical path of the wide-angle optical system at the branch plane BP when reflected or transmitted.

[0650] [Conditional expression corresponding value]

[0651] Example

[0652]

[0653] Example

[0654]

[0655] The above embodiments illustrate specific examples of the present invention, and the invention is not limited to these. The following may be suitably employed without impairing the optical performance of the optical system of this embodiment.

[0656] The optical system of this embodiment may also have optical components such as filters between the lens surface closest to the image surface and the image surface.

[0657] In the optical system of this embodiment, the lens surface can be formed from a spherical or planar surface, or from an aspherical surface. When the lens surface is spherical or planar, lens processing and assembly adjustments become easier, preventing degradation of optical performance due to errors in processing and assembly adjustments, and is therefore preferred. Furthermore, when the lens surface is spherical or planar, the degradation of imaging performance during image plane shift is less, and is therefore preferred.

[0658] When the lens surface is aspherical, the aspherical surface can be formed either by grinding the glass or by molding the glass using a mold with an aspherical shape, or it can be formed on the surface of the resin bonded to the glass. Furthermore, in the optical system of this embodiment, the lens surface can also be a diffraction surface, and the lens can be a refractive index distribution lens (GRIN lens) or a plastic lens.

[0659] Alternatively, an anti-reflective coating with high transmittance over a wide wavelength range can be applied to the lens surface of the lens constituting the optical system of this embodiment. This reduces glare and ghosting, achieving high-contrast optical performance.

[0660] In the optical system of this embodiment, it is also possible to omit the component that serves as an aperture stop and instead use a lens frame or the like to replace it.

[0661] Next, based on Figure 48 The optical device having the optical system 1 of this embodiment will be described. Figure 48 This is a schematic diagram of an optical device 10 equipped with the optical system 1 of this embodiment.

[0662] The optical device 10 includes the optical system 1, information processing device 2, drive unit 3, first imaging element IS1 and second imaging element IS2 described in the first embodiment above.

[0663] The first imaging element IS1 and the second imaging element IS2 are imaging elements composed of CCD or CMOS, etc. In the optical device 10, the first imaging element IS1 and the second imaging element IS2 are respectively disposed on the image plane I1 and image plane I2 of the optical system 1, and output image information corresponding to the incident light. The information processing device 2 performs processing using the image information output by the first imaging element IS1 and the second imaging element IS2 respectively.

[0664] The drive unit 3, for example, has an actuator that changes the orientation of the optical system 1 according to the control signal received from the information processing device 2. At this time, the information processing device 2 can generate the control signal based on image information representing the image of the wide-angle side optical system.

[0665] Figure 49 This diagram illustrates an example of the operation of the drive unit 3 in the optical device 10 of this embodiment. In the optical system 1 of the first embodiment, the first optical system OS1, which images on the image plane I1, is a wide-angle side optical system, and the second optical system OS2, which images on the image plane I2, is a telephoto side optical system. Therefore, the range represented by the image information PW1 output by the first imaging element IS1 is larger than the range represented by the image information PT1 output by the second imaging element IS2.

[0666] exist Figure 49 In this example, object OBJ is included in image information PW1 but not in image information PT1. Information processing device 2 detects object OBJ from image information PW1 and determines the orientation of object OBJ based on the position of object OBJ in image information PW1 and the focal length of the first optical system OS1. Then, information processing device 2 generates a control signal to cause drive unit 3 to change the orientation of optical system 1 so that it faces the determined object OBJ.

[0667] By changing the orientation of the telephoto side optical system of the optical system 1 through the operation of the drive unit 3 according to such a control signal, the optical device 10 can acquire image information PT2 containing the object OBJ. In this way, the optical device 10 of this embodiment can appropriately change the orientation of the optical system 1 based on the wide range of conditions represented by the image obtained by the wide-angle side optical system.

[0668] The drive unit 3 can also be configured to change the orientation of the optical system 1 by changing the orientation of the optical device 10.

[0669] The optical device 10 can also generate image information based on image information representing the image of the wide-angle side optical system and image information representing the image of the telephoto side optical system. Figure 50 This is an example of image information generated by the optical device 10 of this embodiment.

[0670] The information processing device 2 generates a magnified image PWE by magnifying a portion of the image information PW3 representing the image of the wide-angle side optical system. The magnified image PWE is an example of the first image information obtained by magnifying a portion of the image of the wide-angle side optical system.

[0671] Information processing device 2 generates a composite image PS comprising a magnified image PWE and image information PT3 representing the image of the telescope-side optical system. Image information PT3 is an example of second image information representing at least a portion of the image of the telescope-side optical system. Information processing device 2 operates as a synthesis unit that synthesizes the first image information and the second image information.

[0672] exist Figure 50 In the example, the information processing device 2 generates an image of the field of view between the wide-angle optical system and the telephoto optical system by magnifying the image information PW3 representing the image of the wide-angle optical system. By transforming the image of the central portion of the image into an image obtained by magnifying the image information PW3 representing the image of the wide-angle optical system, and using at least a portion of the image information PT3 representing the image of the telephoto optical system, a composite image PS that clearly represents the central portion can be obtained. At this time, the information processing device 2 can also generate the composite image PS using an image obtained by reducing at least a portion of the image information PT3.

[0673] The composite image PS output by the optical device 10 according to this embodiment can compare the portion contained in the image obtained by the wide-angle side optical system and the portion contained in the image obtained by the telephoto side optical system.

[0674] Finally, based on Figure 51 A general description of the manufacturing method of the optical system 1 of this embodiment will be given. Figure 51 This is a flowchart illustrating a general method for manufacturing the optical system 1 according to this embodiment.

[0675] Figure 51 The first manufacturing method of the optical system 1 of this embodiment shown includes the following steps S1 to S4.

[0676] Step S1: Prepare the front lens group GF with negative optical power, the optical path branching component OB with branching surface BP, the first rear lens group GR1, and the second rear lens group GR2.

[0677] Step S2: Configure the first optical system OS1 in such a way that it includes a front lens group GF, an optical path branching component OB, and a first rear lens group GR1 for the first light reflected at the branching surface BP.

[0678] Step S3: Configure the second optical system OS2 in such a way that it has a front lens group GF, an optical path branching component OB, and a second rear lens group GR2 for the second light transmitted at the branching surface BP.

[0679] Step S4: Configure the second optical system OS2 to have a total system focal length that is different from that of the first optical system OS1.

[0680] According to the manufacturing method of the optical system of this embodiment, it is possible to manufacture an optical system that branches the incident light and images them appropriately.

[0681] It is intended to be understood that those skilled in the art can make various changes, substitutions and modifications to this disclosure without departing from its spirit and scope.

[0682] Explanation of reference numerals in the attached figures

[0683] 1 Optical System

[0684] OS1 First Optical System

[0685] OS2 Second Optical System

[0686] OB, OBx, OBy optical path branch components

[0687] BP, BPx, BPy branch surfaces

[0688] ST1, ST2, STM, STa, STb Aperture Stops

[0689] Image planes I1, I2, Ia, Ib, Ic, Id

[0690] RAP1, RAP2, RAP3 right-angle prisms

[0691] IS1 First Imaging Element

[0692] IS2 Second Imaging Element

[0693] 10 Optical Equipment

[0694] 2. Information processing device

[0695] 3 Drive Unit

Claims

1. An optical system comprising: A first optical system, comprising, starting from the object side, a front lens group having negative optical power, a light path branching component having a branching surface, and a first rear lens group, wherein the branching surface transmits a portion of the incident light and reflects at least a portion of the incident light that is different from the transmitted light; the first rear lens group receives a first light incident as at least a portion of the light reflected from the branching surface; and The second optical system includes, starting from the object side, the front lens group, the optical path branching component, and the second rear lens group for the second light to be incident upon, wherein the second light is at least a portion of the light transmitted through the branching surface. The second optical system has a total focal length that is different from that of the first optical system.

2. The optical system according to claim 1, wherein, The following condition is satisfied:

1. 20 < fB / fA < 13.00 in, fB: The longer of the total focal length of the first optical system and the total focal length of the second optical system. fA: The shorter of the total focal length of the first optical system and the total focal length of the second optical system.

3. The optical system according to claim 1 or 2, wherein, The following condition is satisfied: 0.20 < -fF / fA < 10.00 in, fF: Focal length of the front lens group fA: The shorter of the total focal length of the first optical system and the total focal length of the second optical system.

4. The optical system according to any one of claims 1 to 3, wherein, The following condition is satisfied: 0.05 < -fF / fB < 3.50 in, fF: Focal length of the front lens group fB: The longer of the total focal length of the first optical system and the total focal length of the second optical system.

5. The optical system according to any one of claims 1 to 4, wherein, The following condition is satisfied:

3. 50 < -f1 / fA < -50.30 in, f1: The focal length of the lens in the front lens group positioned closest to the object. fA: The shorter of the total focal length of the first optical system and the total focal length of the second optical system.

6. The optical system according to any one of claims 1 to 5, wherein, The following condition is satisfied: 0.25 < -f1 / fB < 15.00 in, f1: The focal length of the lens in the front lens group positioned closest to the object. fB: The longer of the total focal length of the first optical system and the total focal length of the second optical system.

7. The optical system according to any one of claims 1 to 6, wherein, The following condition is satisfied: 0.04 < -D12 / f1 < 1.50 in, D12: The distance on the optical axis between the image-plane side lens of the lens of the front lens group positioned closest to the object and the object-plane side lens of the lens of the front lens group positioned adjacent to the image-plane side of the lens of the front lens group positioned closest to the object. f1: The focal length of the lens of the front lens group positioned closest to the object.

8. The optical system according to any one of claims 1 to 7, wherein, The following condition is satisfied: 0.30 < TLB / TLA < 3.50 in, TLB: The total optical length of the optical system that has the longer overall focal length between the first optical system and the second optical system. TLA: The total optical length of the optical system of the shorter optical system of the first optical system and the second optical system.

9. The optical system according to any one of claims 1 to 8, wherein, The following condition is satisfied:

0. 30＜-（r12+r11） / （r12-r11）＜4.70 in, r12: The radius of curvature of the lens surface on the image plane side of the lens of the front lens group positioned closest to the object. r11: The radius of curvature of the lens surface on the object side of the lens group located at the position closest to the object side.

10. The optical system according to any one of claims 1 to 9, wherein, The following condition is satisfied:

0. 10＜（r21+r12） / （r21-r12）＜3.30 in, r21: The radius of curvature of the lens surface on the object side of the lens adjacent to the image plane side of the lens of the front lens group located at the position closest to the object side. r12: The radius of curvature of the lens surface on the image plane side of the lens of the front lens group located at the position closest to the object.

11. The optical system according to any one of claims 1 to 10, wherein, The following condition is satisfied: 0.30 < D12 / fA < 11.30 in, D12: The distance on the optical axis between the image-plane side lens of the lens of the front lens group positioned closest to the object and the object-plane side lens of the lens of the front lens group positioned adjacent to the image-plane side of the lens of the front lens group positioned closest to the object. fA: The shorter of the total focal length of the first optical system and the total focal length of the second optical system.

12. The optical system according to any one of claims 1 to 11, wherein, The following condition is satisfied: 0.07 < D12 / fB < 4.30 in, D12: The distance on the optical axis between the image-plane side lens of the lens of the front lens group positioned closest to the object and the object-plane side lens of the lens of the front lens group positioned adjacent to the image-plane side of the lens of the front lens group positioned closest to the object. fB: The longer of the total focal length of the first optical system and the total focal length of the second optical system.

13. The optical system according to any one of claims 1 to 12, wherein, The following condition is satisfied:

1. 20 < ωA / ωB < 15.00 in, ωA: The half-field angle of the optical system with the shorter overall focal length between the first and second optical systems. ωB: The half field of view of the optical system with the longer overall focal length in the first optical system and the second optical system.

14. The optical system according to any one of claims 1 to 13, wherein, The following condition is satisfied: 0.20 < fpA / fpB < 2.50 in, fpA: The combined focal length of the positive lens elements continuously arranged on the image plane side in the rear lens group of the optical system comprising the optical system with the shorter overall focal length in the first optical system and the second optical system, starting from the positive lens element positioned closest to the object side. fpB: The combined focal length of the positive lens elements continuously arranged on the image plane side in the rear lens group of the optical system comprising the optical system with the longer overall focal length in the first optical system and the second optical system, starting from the positive lens element positioned closest to the object side.

15. The optical system according to any one of claims 1 to 14, wherein, The following condition is satisfied: 0.33 < |fRB / fRA| < 65.00 in, fRB: The focal length of the rear lens group included in the optical system of the first and second rear lens groups, specifically the optical system with the longer overall focal length in the first and second optical systems. fRA: The focal length of the rear lens group included in the optical system of the first rear lens group and the second rear lens group, whichever has the shorter overall focal length in the first optical system and the second optical system.

16. The optical system according to any one of claims 1 to 15, wherein, The following condition is satisfied: 7.00 < TLB / fA < 110.00 in, TLB: The total optical length of the optical system that has the longer overall focal length between the first optical system and the second optical system. fA: The shorter of the total focal length of the first optical system and the total focal length of the second optical system.

17. The optical system according to any one of claims 1 to 16, wherein, The following condition is satisfied: 0.30 < TLA / fB < 20.50 in, TLA: The total optical length of the optical system with the shorter overall focal length between the first optical system and the second optical system. fB: The longer of the total focal length of the first optical system and the total focal length of the second optical system.

18. The optical system according to any one of claims 1 to 17, wherein, The following condition is satisfied:

1. 70 < nd1 < 2.01 in, nd1: The refractive index of the lens of the front lens group positioned closest to the object with respect to the d-line.

19. The optical system according to any one of claims 1 to 17, wherein, The following condition is satisfied:

1. 50 < nd2 < 2.01 in, nd2: The refractive index of the lens with respect to the d-line of the lens arranged adjacent to the image plane side of the lens of the front lens group located at the position closest to the object.

20. The optical system according to any one of claims 1 to 19, wherein, The following condition is satisfied:

1. 55 < ndaveF < 2.01 in, ndaveF: The average refractive index of the lens with respect to the d-line of the front lens group.

21. The optical system according to any one of claims 1 to 20, wherein, The following condition is satisfied: 45°<ωA<120° in, ωA: The half field of view of the optical system with the shorter overall focal length in the first optical system and the second optical system.

22. The optical system according to any one of claims 1 to 20, wherein, The following condition is satisfied: 3°<ωB<30° in, ωB: The half field of view of the optical system with the longer overall focal length in the first optical system and the second optical system.

23. The optical system according to any one of claims 1 to 22, wherein, The following condition is satisfied: 0.10 < Wi / (1-Wi) ≤ 1.00 in, Wi: The reflectivity of the branch surface is defined as follows: when the light path of the shorter focal length in the first optical system and the second optical system is reflected through the branch surface, the reflectivity of the branch surface is defined as follows: when the light path of the shorter focal length in the first optical system and the second optical system is transmitted through the branch surface, the reflectivity of the branch surface is defined as follows.

24. The optical system according to any one of claims 1 to 23, wherein, At least one of the first rear lens group and the second rear lens group has a second optical path branching component, a third rear lens group, and a fourth rear lens group. The second optical path branching component has a second branching surface, which reflects a portion of the incident light and transmits at least a portion of the incident light that is different from the first portion. The third rear lens group allows at least a portion of the light reflected from the second branching surface to be incident, and the fourth rear lens group allows at least a portion of the light transmitted from the second branching surface to be incident.

25. The optical system according to claim 24, wherein, The lens group in the first rear lens group and the second rear lens group, which has the second optical path branching component, the third rear lens group and the fourth rear lens group, has an intermediate lens group between the optical path branching component and the second optical path branching component, and the intermediate lens group has positive optical power.

26. The optical system according to any one of claims 1 to 25, wherein, The image plane of the first optical system and the image plane of the second optical system are arranged on the same plane.

27. The optical system according to claim 26, wherein, The total focal length of the first optical system is longer than that of the second optical system.

28. The optical system according to claim 27, wherein, The first optical system further includes a first optical path changing component and a second optical path changing component between the optical path branching component and the image plane. The first optical path changing component changes the optical path of the light reflected from the branching surface to be parallel to the optical path of the light transmitted through the branching surface. The second optical path changing component shortens the interval between the optical path of the light reflected from the branching surface after being changed by the first optical path changing component and the optical path of the light transmitted through the branching surface.

29. An optical device comprising the optical system according to any one of claims 1 to 28.

30. The optical device according to claim 29, wherein, The device has a driving unit that changes the orientation of the optical system based on image information representing the image of the optical system with the shorter overall focal length in the first optical system and the second optical system.

31. The optical device according to claim 30, wherein, The driving unit changes the orientation of the optical system so that the object detected from the image information enters the field of view of the optical system with the longer overall focal length between the first and second optical systems.

32. The optical device according to any one of claims 29 to 31, wherein, The device includes a compositing unit that combines first image information and second image information. The first image information is an image obtained by magnifying a portion of the image of the optical system with the shorter overall focal length in the first optical system and the second optical system. The second image information represents at least a portion of the image of the optical system with the longer overall focal length in the first optical system and the second optical system.

33. A method of manufacturing an optical system, the optical system having a branching surface that transmits a portion of incident light and reflects at least a portion of the incident light that is different from the first portion, such that a first light and a second light are respectively imaged, the first light being at least a portion of the light reflected from the branching surface, and the second light being at least a portion of the light transmitted from the branching surface, the method of manufacturing comprising: The first optical system is configured such that, starting from the object side, it sequentially includes a front lens group with negative optical power, an optical path branching component having the branching surface, and a first rear lens group for the first light to be incident upon. The second optical system is configured such that, starting from the object side, it sequentially includes the front lens group, the optical path branching component, and the second rear lens group for the second light to be incident upon; as well as The second optical system is configured to have a total system focal length that is different from that of the first optical system.

Images