JP6736820B1 - Lens system, imaging device, and moving body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens system which has a high resolution and suppresses a change in focal position due to a temperature change. A lens system includes, in order from the object side, a positive first lens group 101, an aperture stop S, and a positive second lens group 102, and the image side surface of the first lens group is a concave surface facing the image side. The second lens group includes a negative first lens L1, a positive second lens L2, and a negative third lens L3 having an image side surface whose convex surface faces the image side, and a negative fourth lens L4. , A positive fifth lens L5 and a negative sixth lens L6, and the material of the second lens is glass, and the first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens The material is plastic, f1 is the focal length of the first lens, f3-6 is the focal length of the second lens group, Nd2 is the refractive index of the second lens at the d-line, and Vd2 is the Abbe number of the second lens at the d-line. , The conditional expressions −0.12<1/f1+1/f3-6<0.12, Nd2>1.65, and Vd2>30 are satisfied. [Selection diagram] Figure 1

Description

The present invention relates to a lens system, an imaging device, and a moving body.

The following document discloses an imaging lens for a camera used in an environment where the temperature changes.
Patent Document 1 Japanese Patent Laid-Open No. 2017-173818 Patent Document 2 Japanese Patent No. 5718528

There is a demand for a lens system that suppresses fluctuations in focal position due to temperature changes.

A lens system according to one aspect of the present invention includes, in order from the object side, a positive first lens group, an aperture stop, and a positive second lens group. The first lens group includes a negative first lens whose image side surface is a concave surface facing the image side, and a positive second lens. The second lens group includes a positive third lens having an image side surface whose convex surface faces the image side, a negative fourth lens, a positive fifth lens, and a negative sixth lens. The material of the second lens is glass. The material of the first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens is plastic. f1 is the focal length of the first lens, f3-6 is the focal length of the second lens group, Nd2 is the refractive index of the second lens at the d-line, and Vd2 is the Abbe number of the second lens at the d-line. .12<1/f1+1/f3-6<0.12
Nd2> 1.65
Vd2> 30
To be satisfied.

Conditional expression 0.7<f2/f<1.7 where f2 is the focal length of the second lens and f is the focal length of the entire lens system.
May be satisfied.

Conditional expression 0.6<f3-6/f<2.3
May be satisfied.

Where f3 is the focal length of the third lens, conditional expression 0.4 <f3/f <1.4
May be satisfied.

Conditional expression 1.5 <TT/f <3.5 where TT is the total length of the lens system.
May be satisfied.

An imaging device according to one aspect of the present invention includes the above lens system. The image pickup device includes an image pickup element.

A moving body according to one aspect of the present invention includes the above-described lens system and moves.

The mobile may be an unmanned aerial vehicle.

According to the lens system described above, it is possible to provide a lens system in which the fluctuation of the focal position due to the temperature change is suppressed.

The above summary of the invention does not list all of the features of the present invention. A sub-combination of these feature groups can also be an invention.

The lens configuration of the lens system 100 in the first example is shown together with the filter F and the image sensor IMA. 3 shows spherical aberration, astigmatism, and distortion of the lens system 100 focused on an object at infinity. The lens structure of the lens system 200 in the second example is shown together with the filter F and the image sensor IMA. 3 shows spherical aberration, astigmatism, and distortion of the lens system 200 focused on an object at infinity. The lens configuration of the lens system 300 in the third example is shown together with the filter F and the image sensor IMA. 7 shows spherical aberration, astigmatism, and distortion of the lens system 300 focused on an object at infinity. The lens configuration of the lens system 400 in the fourth example is shown together with the filter F and the image sensor IMA. 7 shows spherical aberration, astigmatism, and distortion of the lens system 400 in a state of being focused on an infinitely distant subject. 1 schematically illustrates an example of a mobile system 10 including an unmanned aerial vehicle (UAV) 40 and a controller 50. An example of the functional block of UAV40 is shown. It is an appearance perspective view showing an example of stabilizer 3000.

Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Further, not all of the combinations of features described in the embodiments are essential to the means for solving the invention. It is apparent to those skilled in the art that various modifications and improvements can be added to the following embodiments. It is apparent from the description of the scope of claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

The claims, the description, the drawings, and the abstract contain the subject matter of copyright protection. The copyright owner has no objection to the reproduction of any of these documents by anyone as it appears in the JPO file or record. However, in all other cases, all copyrights are reserved.

Embodiments of lens systems are disclosed in connection with FIGS. 1, 3, 5, and 7. As disclosed in each example, the lens system of one embodiment includes, in order from the object side, a positive first lens group, an aperture stop, and a positive second lens group. The first lens group includes a negative first lens whose image side surface is a concave surface facing the image side, and a positive second lens. The second lens group includes a positive third lens having an image side surface whose convex surface faces the image side, a negative fourth lens, a positive fifth lens, and a negative sixth lens. The material of the second lens is glass, and the material of the first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens is plastic. f1 is the focal length of the first lens, f3-6 is the focal length of the second lens group, Nd2 is the refractive index of the second lens at the d line, and Vd2 is the Abbe number of the second lens at the d line. 1, Conditional Expression 2 and Conditional Expression 3 are satisfied.
−0.12<1/f1+1/f3-6<0.12 (conditional expression 1)
Nd2> 1.6 (conditional expression 2)
Vd2> 30 (conditional expression 3)

Generally, a plastic lens has a larger variation in the refractive index with a temperature change than a glass lens. Therefore, when the lens system does not have a focus mechanism, it is desired to optically suppress the performance variation due to the temperature change. In particular, it is desired to optically suppress the fluctuation of the focal position due to the temperature change. With the configuration included in the lens system described above, it is possible to realize a lens system that is relatively small, has a high resolving power, and suppresses fluctuations in the focal position due to temperature changes.

Conditional expression 1 defines the refracting power of the second lens group which is composed of the first lens made of plastic material and the lenses made of all plastic material. By satisfying the conditional expression 1, it is possible to balance the positive refractive power and the negative refractive power of the lens made of a plastic material, and it is possible to suppress the fluctuation of the focal position due to the temperature change. Conditional expressions 2 and 3 define the refractive index and the Abbe number of the second lens at the d-line, respectively. By satisfying conditional expressions 2 and 3, it is possible to realize downsizing and excellent correction of chromatic aberration.

It is more preferable to satisfy the following conditional expression 1-1.
-0.09 <1/f1+1/f3-6 <0.09 (conditional expression 1-1)
By satisfying the conditional expression 1-1, the above effect becomes more remarkable.

It is preferable that the following conditional expression 4 is satisfied, where f2 is the focal length of the second lens and f is the focal length of the entire lens system.
0.7 <f2/f <1.7 (conditional expression 4)

Conditional expression 4 defines the relationship between the focal length of the second lens and the focal length of the entire lens system. If the upper limit of conditional expression 4 is exceeded, the refractive power of the second lens becomes weak, and the refractive power of the plastic lens other than the second lens becomes relatively strong. Therefore, the variation in the focal position when the temperature changes tends to increase. If the lower limit of conditional expression 4 is exceeded, the refractive power of the second lens becomes relatively strong. Therefore, it becomes difficult to correct the aberration, and the performance variation due to the assembly error increases. By satisfying the conditional expression 4, it is possible to suppress the variation in the focal position when the temperature changes. In addition, aberration correction becomes easy, and performance variations due to assembly errors can be suppressed.

It is more preferable to satisfy the following conditional expression 4-1.
0.9 <f2/f <1.5 (conditional expression 4-1)
By satisfying conditional expression 4-1, the above effect becomes more remarkable.

It is preferable that the lens system satisfies the following conditional expression 5.
0.6 <f3-6/f <2.3 (conditional expression 5)

Conditional expression 5 defines the relationship between the focal length of the second lens group and the focal length of the entire lens system. When the upper limit of conditional expression 5 is exceeded, the refractive power of the second lens group becomes relatively weak. Therefore, it is difficult to downsize the lens system. If the lower limit of conditional expression (5) is exceeded, the refractive power of the second lens group will become relatively strong. Therefore, it becomes difficult to correct aberrations, and the performance deterioration due to decentering of each lens becomes remarkable. By satisfying the conditional expression 5, the lens system can be easily downsized, and the aberration can be easily corrected, so that the performance deterioration due to the eccentricity of the lens can be suppressed.

It is more preferable to satisfy the following conditional expression 5-1.
0.9 <f3-6/f <2.0 (conditional expression 5-1)
By satisfying conditional expression 5-1, the above effect becomes more remarkable.

It is preferable that the following conditional expression 6 is satisfied with f3 being the focal length of the third lens.
0.4 <f3/f <1.4 (conditional expression 6)

Conditional expression 6 defines the relationship between the focal length of the third lens and the focal length of the entire lens system. If the upper limit of conditional expression 6 is exceeded, the refractive power of the third lens becomes relatively weak. Therefore, the size of the lens system is increased. If the lower limit of conditional expression (6) is exceeded, the refractive power of the third lens becomes relatively strong. Therefore, it becomes difficult to correct the axial aberration in particular. By satisfying conditional expression 6, the lens system can be downsized. Further, it becomes easy to correct the axial aberration.

It is more preferable to satisfy the following conditional expression 6-1.
0.55 <f3/f <1.25 (conditional expression 6-1)
By satisfying conditional expression 6-1, the above effect becomes more remarkable.

It is preferable that the following conditional expression 7 is satisfied with TT being the total length of the optical system.
1.5 <TT/f <3.5 (conditional expression 7)

Conditional expression 7 defines the relationship between the total length of the optical system and the focal length of the entire optical system. If the upper limit of conditional expression 7 is exceeded, the total length becomes long. When the lower limit of conditional expression 7 is exceeded, the refracting power of each lens becomes strong as the overall length is shortened, and it becomes difficult to correct aberrations. By satisfying conditional expression 7, the total length can be shortened. In addition, aberration correction becomes easy.

Next, a lens configuration of an example according to the embodiment of the lens system will be described.

FIG. 1 shows the lens configuration of the lens system 100 in the first embodiment together with the filter F and the image sensor IMA. The lens system 100 includes a first lens group 101, an aperture stop S, and a second lens group 102 in order from the object side. The optical filter F is provided on the object side of the image sensor IMA. The light that has passed through the lens system 100 and the filter F enters the image sensor IMA.

In the description of each embodiment of the lens system, “Ln” indicates a lens. Here, n following L is an integer of 1 or more. “N” indicates the nth lens from the object side. In each embodiment, Ln is a symbol assigned to indicate that the lens is the nth lens from the object side. In the description of each example, the lens to which the symbol Ln is assigned does not mean that the lens to which the same symbol Ln is assigned in the other examples is the same lens.

Meanings of symbols and the like used in the description of each embodiment of the lens system will be described. The plurality of surfaces of the lens system are identified by the surface number i, where i is a natural number. The first surface of the lens when viewed from the object side is the first surface, and thereafter, the surface numbers are counted in the order in which the light rays pass through the surface. “STO” in the surface number represents the aperture surface of the aperture stop S. “Di” indicates the interval on the optical axis between the i-th surface and the (i+1)-th surface.

“F” indicates the focal length. “Fno” indicates an F number. “Ω” indicates a half angle of view. "Y" indicates the maximum image height. “TT” indicates the total length of the optical system when focusing on an object at infinity. “R” indicates a radius of curvature. In the radius of curvature, “∞” indicates a plane. “Nd” indicates a refractive index. “Vd” indicates the Abbe number. The refractive index Nd and the Abbe number Vd are values at the d-line (λ=587.6 nm).

Table 1 shows lens data of the lenses included in the lens system 100. In Table 1, Di, Nd, and Vd are shown in association with the surface number i.

In Table 1, the surface marked with * is a surface having an aspherical shape. Tables 2 and 3 show surface numbers of surfaces having an aspherical shape and aspherical surface parameters. In Table 2, “κ” indicates a conic constant (conic constant). In Tables 2 and 3, "A", "B", "C", "D", "E", "F", "G", "H", and "I" are quaternary and 6 respectively. Next-order, eighth-order, tenth-order, 12th-order, 14th-order, 16th-order, 18th-order, and 20th-order aspherical coefficients. Further, when i is an integer, in the aspherical surface coefficient, "E-i" indicates an exponential expression having a base of 10, that is, "10- ⁱ ".

Let “x” be the distance in the optical axis direction from the apex of the lens surface, “y” be the height in the direction perpendicular to the optical axis, and “c” be the paraxial curvature at the apex of the lens. It is defined by the following formula.
^{x = cy 2 / (1+ (} 1- (1 + κ) c 2 y 2) 1/2) + + Ay 4 + By 6 + Cy 8 + Dy 10 + Ey 12 + Fy 14 + Gy 16 Hy 18 + Iy 20
Note that “x” is also called a sag amount. "Y" is also called image height. Paraxial curvature is the reciprocal of the radius of curvature.

Table 4 shows the focal lengths f, Fno, half angle of view ω, image height Y, and optical system total length TT of the entire lens system 100 focused on an infinitely distant subject.

The lens system 100 includes, in order from the object side, a first lens group 101 having a positive refractive power, an aperture stop S, and a second lens group 102 having a positive refractive power. The first lens group 101 includes a negative meniscus lens L1 whose image side surface is a concave surface facing the image side, and a biconvex positive lens L2 made of a glass material.

The second lens group 102 includes a positive lens L3 having an image side surface having a convex surface facing the image side, a negative lens L4 having an image side surface having a concave surface facing the image side, and a positive lens L5 having an image side surface having a convex surface facing the image side. And a negative lens L6 having an image side surface whose concave surface faces the image side.

FIG. 2 shows spherical aberration, astigmatism, and distortion of the lens system 100 focused on an object at infinity. In spherical aberration, the alternate long and short dash line indicates the C line (656.27 nm), the solid line indicates the d line (587.56 nm), and the broken line indicates the g line (435.84 nm). In the astigmatism, the solid line shows the value of the d-line sagittal image plane, and the broken line shows the value of the d-line meridional image plane. In the distortion aberration, the solid line shows the value of d line. From each aberration diagram, it is apparent that the lens system 100 has excellently corrected various aberrations and excellent imaging performance.

FIG. 3 shows the lens configuration of the lens system 200 according to the second example together with the filter F and the image sensor IMA. The lens system 200 includes a first lens group 201, an aperture stop S, and a second lens group 202 in order from the object side. The optical filter F is provided on the object side of the image sensor IMA.

Table 5 shows lens data of the lenses included in the lens system 200. In Table 5, Di, Nd, and Vd are shown in association with the surface number i.

In Table 5, the surface marked with * is a surface having an aspherical shape. Tables 6 and 7 show surface numbers of surfaces having an aspherical shape and aspherical surface parameters. In Table 6, “κ” indicates a conic constant (conic constant). In Tables 6 and 7, “A”, “B”, “C”, “D”, “E”, “F”, “G”, “H”, and “I” are quaternary and 6 respectively. Next-order, eighth-order, tenth-order, 12th-order, 14th-order, 16th-order, 18th-order, and 20th-order aspherical coefficients. Further, when i is an integer, in the aspherical surface coefficient, "E-i" indicates an exponential expression having a base of 10, that is, "10- ⁱ ".

Table 8 shows the focal lengths f, Fno, half angle of view ω, image height Y, and optical system total length TT of the entire lens system 200 focused on an infinitely distant subject.

The lens system 200 includes, in order from the object side, a first lens group 201 having a positive refractive power, an aperture stop S, and a second lens group 202 having a positive refractive power. The first lens group 201 includes a negative meniscus lens L1 whose image-side surface is a concave surface facing the image side, and a biconvex positive lens L2 made of a glass material. The second lens group 202 includes a positive lens L3 having an image side surface whose convex surface faces the image side, a negative lens L4 whose image side surface has a concave surface facing the image side, and a positive lens L5 whose image side surface has a convex surface facing the image side. And a negative lens L6 having an image side surface whose concave surface faces the image side.

FIG. 4 shows spherical aberration, astigmatism, and distortion of the lens system 200 focused on an infinite subject. In spherical aberration, the alternate long and short dash line indicates the C line (656.27 nm), the solid line indicates the d line (587.56 nm), and the broken line indicates the g line (435.84 nm). In the astigmatism, the solid line shows the value of the d-line sagittal image plane, and the broken line shows the value of the d-line meridional image plane. In the distortion aberration, the solid line shows the value of d line. From each aberration diagram, it is apparent that the lens system 200 has various aberrations favorably corrected and has excellent imaging performance.

FIG. 5 shows the lens configuration of the lens system 300 in the third example together with the filter F and the image sensor IMA. The lens system 300 includes a first lens group 301, an aperture stop S, and a second lens group 302 in order from the object side. The optical filter F is provided on the object side of the image sensor IMA.

Table 9 shows lens data of the lenses included in the lens system 300. In Table 9, Di, Nd, and Vd are shown in association with the surface number i.

In Table 9, a surface having a surface number with * is a surface having an aspherical shape. Tables 10 and 11 show surface numbers of surfaces having an aspherical shape and aspherical surface parameters. In Table 10, “κ” indicates a conic constant (conic constant). In Tables 10 and 11, "A", "B", "C", "D", "E", "F", "G", "H", and "I" are quaternary and 6 respectively. Next-order, eighth-order, tenth-order, 12th-order, 14th-order, 16th-order, 18th-order, and 20th-order aspherical coefficients. Further, when i is an integer, in the aspherical surface coefficient, "E-i" indicates an exponential expression having a base of 10, that is, "10- ⁱ ".

Table 12 shows the focal lengths f, Fno, half angle of view ω, image height Y, and optical system total length TT of the entire lens system 300 focused on an infinitely distant subject.

The lens system 300 includes, in order from the object side, a first lens group 301 having a positive refractive power, an aperture stop S, and a second lens group 302 having a positive refractive power. The first lens group 301 includes a biconcave negative lens L1 and a biconvex positive lens L2 made of a glass material. The second lens group 302 includes a positive lens L3 having an image side surface having a convex surface facing the image side, a negative lens L4 having an image side surface having a concave surface facing the image side, and a positive lens L5 having an image side surface having a convex surface facing the image side. And a negative lens L6 having an image side surface whose concave surface faces the image side.

FIG. 6 shows spherical aberration, astigmatism, and distortion of the lens system 300 focused on an infinite subject. In spherical aberration, the alternate long and short dash line indicates the C line (656.27 nm), the solid line indicates the d line (587.56 nm), and the broken line indicates the g line (435.84 nm). In the astigmatism, the solid line shows the value of the d-line sagittal image plane, and the broken line shows the value of the d-line meridional image plane. In the distortion aberration, the solid line shows the value of d line. From each aberration diagram, it is apparent that the lens system 300 has well-corrected various aberrations and has excellent imaging performance.

FIG. 7 shows the lens configuration of the lens system 400 in the fourth example together with the filter F and the image sensor IMA. The lens system 400 includes a first lens group 401, an aperture stop S, and a second lens group 402 in order from the object side. The optical filter F is provided on the object side of the image sensor IMA.

Table 13 shows lens data of the lenses included in the lens system 300. In Table 13, Di, Nd, and Vd are shown in association with the surface number i.

In Table 13, the surface marked with * is a surface having an aspherical shape. Tables 14 and 15 show surface numbers of surfaces having an aspherical shape and aspherical surface parameters. In Table 14, “κ” indicates a conic constant (conic constant). In Tables 14 and 15, "A", "B", "C", "D", "E", "F", "G", "H", and "I" are quaternary and 6 respectively. Next-order, eighth-order, tenth-order, 12th-order, 14th-order, 16th-order, 18th-order, and 20th-order aspherical coefficients. Further, when i is an integer, in the aspherical surface coefficient, "E-i" indicates an exponential expression having a base of 10, that is, "10- ⁱ ".

Table 16 shows the focal lengths f, Fno, half angle of view ω, image height Y, and optical system total length TT of the entire lens system 400 focused on an infinitely distant subject.

The lens system 400 includes, in order from the object side, a first lens group 401 having a positive refractive power, an aperture stop S, and a second lens group 402 having a positive refractive power. The first lens group 401 includes a negative meniscus lens L1 having an image side surface having a concave surface facing the image side, and a positive lens L2 made of glass having an object side surface having a convex surface facing the object side. The second lens group 402 includes a positive lens L3 whose image side surface is convex on the image side, a negative lens L4 whose image side surface is concave on the image side, and a positive lens L5 whose image side surface is convex on the image side. And a negative lens L6 having an image side surface whose concave surface faces the image side.

FIG. 8 shows spherical aberration, astigmatism, and distortion of the lens system 400 focused on an infinitely distant subject. In spherical aberration, the alternate long and short dash line indicates the C line (656.27 nm), the solid line indicates the d line (587.56 nm), and the broken line indicates the g line (435.84 nm). In the astigmatism, the solid line shows the value of the d-line sagittal image plane, and the broken line shows the value of the d-line meridional image plane. In the distortion aberration, the solid line shows the value of d line. From each aberration diagram, it is clear that the lens system 400 has various aberrations well corrected and has excellent imaging performance.

Table 17 shows numerical values relating to each conditional expression in the first to fourth examples.

Table 18 shows the focal lengths associated with each conditional expression.

The lens system according to this embodiment can provide a lens system having a relatively high resolution. Further, it is possible to provide a lens system in which the fluctuation of the focal position due to the temperature change is suppressed. In addition, it is possible to provide a relatively small and inexpensive lens system.

The lens system according to this embodiment can be applied to an imaging lens system of an imaging device such as a digital camera or a video camera. The lens system according to this embodiment can be applied to a lens system having no focus mechanism. The lens system according to this embodiment can also be applied to a lens system having a focus mechanism. The lens system according to this embodiment can be applied to a lens system having no zoom mechanism. The lens system according to this embodiment can also be applied to a lens system having a zoom mechanism. The lens system according to this embodiment can be applied to an imaging lens included in a non-interchangeable lens type imaging device. The lens system according to this embodiment can be applied to an interchangeable lens of an interchangeable lens type camera such as a single-lens reflex camera.

Next, a moving body system as an example of a system including the lens system according to the present embodiment will be described.

FIG. 9 schematically illustrates an example of a mobile system 10 including an unmanned aerial vehicle (UAV) 40 and a controller 50. The UAV 40 includes a UAV body 1101, a gimbal 1110, a plurality of imaging devices 1230, and an imaging device 1220. The imaging device 1220 includes a lens device 1160 and an imaging unit 1140. The lens device 1160 includes the lens system described above. The UAV 40 is an example of a moving body that includes the image pickup apparatus having the above-described lens system and moves. The moving body is a concept including, in addition to UAVs, other aircraft moving in the air, vehicles moving on the ground, ships moving on the water, and the like.

The UAV body 1101 includes a plurality of rotary blades. The UAV body 1101 causes the UAV 40 to fly by controlling the rotation of a plurality of rotor blades. The UAV body 1101 flies the UAV 40 by using, for example, four rotors. The number of rotor blades is not limited to four. The UAV 40 may be a fixed wing aircraft that does not have a rotary wing.

The image capturing device 1230 is an image capturing camera that captures an object included in a desired image capturing range. The plurality of image capturing devices 1230 are sensing cameras that capture images around the UAV 40 in order to control the flight of the UAV 40. The imaging device 1230 may be fixed to the UAV body 1101.

Two imagers 1230 may be provided on the front, which is the nose of the UAV 40. Still another two imaging devices 1230 may be provided on the bottom surface of the UAV 40. The two imaging devices 1230 on the front side may be paired and may function as a so-called stereo camera. The two imaging devices 1230 on the bottom side may also be paired and function as a stereo camera. Three-dimensional spatial data around the UAV 40 may be generated based on the images captured by the plurality of imaging devices 1230. The distance to the subject imaged by the plurality of imaging devices 1230 can be specified by the stereo camera of the plurality of imaging devices 1230.

The number of imaging devices 1230 included in the UAV 40 is not limited to four. The UAV 40 only needs to include at least one imaging device 1230. The UAV 40 may include at least one imaging device 1230 on each of the nose, tail, side surface, bottom surface, and ceiling surface of the UAV 40. The imaging device 1230 may include a single focus lens or a fisheye lens. In the description of the UAV 40, the plurality of imaging devices 1230 may be simply referred to as the imaging device 1230.

The controller 50 includes a display unit 54 and an operation unit 52. The operation unit 52 receives an input operation for controlling the attitude of the UAV 40 from the user. The controller 50 transmits a signal for controlling the UAV 40 based on the user operation accepted by the operation unit 52. For example, the operation unit 52 receives an operation of changing the focusing distance of the lens device 1160. The controller 50 transmits to the UAV 40 a signal instructing to change the focus state.

The controller 50 receives an image captured by at least one of the imaging device 1230 and the imaging device 1220. The display unit 54 displays the image received by the controller 50. The display unit 54 may be a touch panel. The controller 50 may receive an input operation from the user via the display unit 54. The display unit 54 may receive a user operation or the like in which the user specifies the position of the subject to be imaged by the imaging device 1220.

The imaging unit 1140 generates and records image data of the optical image formed by the lens device 1160. The lens device 1160 may be provided integrally with the imaging unit 1140. The lens device 1160 may be a so-called interchangeable lens. The lens device 1160 may be detachably attached to the imaging unit 1140.

The gimbal 1110 has a support mechanism that movably supports the imaging device 1220. The imaging device 1220 is attached to the UAV body 1101 via the gimbal 1110. The gimbal 1110 supports the imaging device 1220 so as to be rotatable about the pitch axis. The gimbal 1110 supports the imaging device 1220 rotatably around the roll axis. The gimbal 1110 supports the imaging device 1220 rotatably around the yaw axis. The gimbal 1110 may rotatably support the imaging device 1220 about at least one of a pitch axis, a roll axis, and a yaw axis. The gimbal 1110 may rotatably support the imaging device 1220 around each of the pitch axis, the roll axis, and the yaw axis. The gimbal 1110 may hold the imaging unit 1140. The gimbal 1110 may hold the lens device 1160. The gimbal 1110 may change the imaging direction of the imaging device 1220 by rotating the imaging unit 1140 and the lens device 1160 around at least one of the yaw axis, the pitch axis, and the roll axis.

FIG. 10 shows an example of functional blocks of the UAV 40. The UAV 40 includes an interface 1102, a control unit 1104, a memory 1106, a gimbal 1110, an image pickup unit 1140, and a lens device 1160.

The interface 1102 communicates with the controller 50. The interface 1102 receives various commands from the controller 50. The control unit 1104 controls the flight of the UAV 40 according to the command received from the controller 50. The control unit 1104 controls the gimbal 1110, the imaging unit 1140, and the lens device 1160. The control unit 1104 may be configured by a microprocessor such as CPU or MPU, a microcontroller such as MCU, or the like. The memory 1106 stores programs necessary for the control unit 1104 to control the gimbal 1110, the imaging unit 1140, and the lens device 1160.

The memory 1106 may be a computer-readable recording medium. The memory 1106 may include at least one of SRAM, DRAM, EPROM, EEPROM, and flash memory such as USB memory. The memory 1106 may be provided in the housing of the UAV 40. It may be detachably provided from the housing of the UAV 40.

The gimbal 1110 has a control unit 1112, a driver 1114, a driver 1116, a driver 1118, a drive unit 1124, a drive unit 1126, a drive unit 1128, and a support mechanism 1130. The drive unit 1124, the drive unit 1126, and the drive unit 1128 may be motors.

The support mechanism 1130 supports the imaging device 1220. The support mechanism 1130 movably supports the imaging direction of the imaging device 1220. The support mechanism 1130 supports the imaging unit 1140 and the lens device 1160 so as to be rotatable around the yaw axis, the pitch axis, and the roll axis. The support mechanism 1130 includes a rotation mechanism 1134, a rotation mechanism 1136, and a rotation mechanism 1138. The rotation mechanism 1134 uses the drive unit 1124 to rotate the imaging unit 1140 and the lens device 1160 about the yaw axis. The rotation mechanism 1136 rotates the imaging unit 1140 and the lens device 1160 about the pitch axis using the driving unit 1126. The rotation mechanism 1138 rotates the imaging unit 1140 and the lens device 1160 around the roll axis by using the driving unit 1128.

The control unit 1112 outputs an operation command indicating each rotation angle to the driver 1114, the driver 1116, and the driver 1118 according to the operation command of the gimbal 1110 from the control unit 1104. The driver 1114, the driver 1116, and the driver 1118 drive the drive unit 1124, the drive unit 1126, and the drive unit 1128 according to the operation command indicating the rotation angle. The rotation mechanism 1134, the rotation mechanism 1136, and the rotation mechanism 1138 are driven and rotated by the driving unit 1124, the driving unit 1126, and the driving unit 1128, respectively, and change the postures of the imaging unit 1140 and the lens device 1160.

The image capturing unit 1140 captures an image with light that has passed through the lens system 1168. The image pickup unit 1140 includes a control unit 1222, an image pickup element 1221, and a memory 1223. The control unit 1222 may be configured by a microprocessor such as a CPU or MPU, a microcontroller such as an MCU, or the like. The control unit 1222 controls the imaging unit 1140 and the lens device 1160 according to an operation command from the control unit 1104 to the imaging unit 1140 and the lens device 1160. The control unit 1222 outputs a control command for the lens apparatus 1160 to the lens apparatus 1160 based on the signal received from the controller 50. The control command may be a command to vibrate the lens system 1168 or a command to detect the temperature of the lens system 1168.

The memory 1223 may be a computer-readable recording medium and may include at least one of SRAM, DRAM, EPROM, EEPROM, and flash memory such as USB memory. The memory 1223 may be provided inside the housing of the imaging unit 1140. The image capturing unit 1140 may be detachably provided from the housing.

The imaging element 1221 is held inside the housing of the imaging unit 1140, generates image data of an optical image formed via the lens device 1160, and outputs the image data to the control unit 1222. The control unit 1222 stores the image data output from the image sensor 1221 in the memory 1223. The control unit 1222 may output the image data to the memory 1106 via the control unit 1104 and store the image data.

The lens device 1160 includes a control unit 1162, a memory 1163, a drive mechanism 1161, and a lens system 1168. As the lens system 1168, the lens system according to the above embodiment can be applied.

The control unit 1162 may vibrate the lens system 1168 according to a control command from the control unit 1222. The drive mechanism 1161 vibrates the lens system 1168. The drive mechanism 1161 includes, for example, an actuator. The image formed by the lens system 1168 of the lens device 1160 is captured by the image capturing unit 1140.

The lens device 1160 may be provided integrally with the imaging unit 1140. The lens device 1160 may be a so-called interchangeable lens. The lens device 1160 may be detachably attached to the imaging unit 1140.

The imaging device 1230 includes a control unit 1232, a control unit 1234, an image sensor 1231, a memory 1233, and a lens 1235. The control unit 1232 may be configured by a microprocessor such as a CPU or MPU, a microcontroller such as an MCU, or the like. The control unit 1232 controls the image sensor 1231 according to an operation command of the image sensor 1231 from the control unit 1104.

The control unit 1234 may be configured by a microprocessor such as CPU or MPU, a microcontroller such as MCU, or the like. The control unit 1234 may control the focus of the lens 1235 according to the operation command to the lens 1235. The control unit 1234 may control the aperture stop included in the lens 1235 according to the operation command to the lens 1235.

The memory 1233 may be a computer-readable recording medium. The memory 1233 may include at least one of SRAM, DRAM, EPROM, EEPROM, and flash memory such as USB memory.

The image sensor 1231 generates image data of an optical image formed via the lens 1235 and outputs the image data to the control unit 1232. The control unit 1232 stores the image data output from the image sensor 1231 in the memory 1233.

In the present embodiment, the UAV 40 includes a control unit 1104, a control unit 1112, a control unit 1222, a control unit 1232, a control unit 1234, and a control unit 1162. However, any one of the control unit 1104, the control unit 1112, the control unit 1222, the control unit 1232, the control unit 1234, and the control unit 1162 may execute the process executed by any one of the control units. The processes executed by the control unit 1104, the control unit 1112, the control unit 1222, the control unit 1232, the control unit 1234, and the control unit 1162 may be executed by one control unit. In this embodiment, the UAV 40 includes a memory 1106, a memory 1223, and a memory 1233. Information stored in at least one of memory 1106, memory 1223, and memory 1233 may be stored in one or more other memory 1106, memory 1223, and memory 1233.

Next, a stabilizer as an example of a system including the lens system according to the above embodiment will be described.

FIG. 11 is an external perspective view showing an example of the stabilizer 3000. Stabilizer 3000 is another example of a moving body. For example, the camera unit 3013 included in the stabilizer 3000 may include an imaging device having the same configuration as the imaging device 1220. The camera unit 3013 may include a lens device having the same configuration as the lens device 1160.

The stabilizer 3000 includes a camera unit 3013, a gimbal 3020, and a handle 3003. The gimbal 3020 rotatably supports the camera unit 3013. The gimbal 3020 has a pan axis 3009, a roll axis 3010, and a tilt axis 3011. The gimbal 3020 rotatably supports the camera unit 3013 around the pan axis 3009, the roll axis 3010, and the tilt axis 3011. The gimbal 3020 is an example of a support mechanism.

The camera unit 3013 is an example of an imaging device. The camera unit 3013 has a slot 3014 for inserting a memory. The gimbal 3020 is fixed to the handle 3003 via the holder 3007.

The handle portion 3003 has various buttons for operating the gimbal 3020 and the camera unit 3013. The handle portion 3003 includes a shutter button 3004, a recording button 3005, and an operation button 3006. By pressing the shutter button 3004, a still image can be recorded by the camera unit 3013. By pressing the record button 3005, a moving image can be recorded by the camera unit 3013.

The device holder 3001 is fixed to the handle 3003. The device holder 3001 holds a mobile device 3002 such as a smartphone. The mobile device 3002 is communicatively connected to the stabilizer 3000 via a wireless network such as WiFi. Thereby, the image captured by the camera unit 3013 can be displayed on the screen of the mobile device 3002.

Also in the stabilizer 3000, since the camera unit 3013 includes the lens system according to the above-described embodiment, the image size is relatively large and a bright image can be obtained. Further, the camera unit 3013 can be downsized.

The UAV 40 and the stabilizer 3000 have been described above as examples of the moving body. The imaging device having the same configuration as the imaging device 1220 may be attached to a moving body other than the UAV 40 and the stabilizer 3000.

The execution order of each process such as the operation, procedure, step, and step in the device, system, program, and method shown in the claims, the specification, and the drawings is, in particular, “before” or “prior to”. It is possible to realize in any order unless the output of the previous process is used in the subsequent process. Even if the operation flow in the claims, the description, and the drawings is described by using “first,” “next,” and the like for convenience, it means that it is essential to carry out in this order. Not a thing.

10 Mobile System 40 UAV
50 controller 52 operation unit 54 display unit 1101 UAV main body 1102 interface 1104 control unit 1106 memory 1110 gimbal 1112 control units 1114, 1116, 1118 drivers 1124, 1126, 1128 drive unit 1130 support mechanism 1134, 1136, 1138 rotation mechanism 1140 image pickup unit 1160 Lens device 1161 Drive mechanism 1162 Control unit 1163 Memory 1168 Lens system 1220, 1230 Imaging device 1221 Imaging device 1222 Control unit 1223 Memory 1231 Imaging device 1232 Control unit 1233 Memory 1234 Control unit 1235 Lens 100, 200, 300, 400 Lens system 101, 201, 301, 401 First lens group 102, 202, 302, 402 Second lens group 3000 Stabilizer 3001 Device holder 3002 Mobile device 3003 Handle 3004 Shutter button 3005 Record button 3006 Operation button 3007 Holder 3009 Pan axis 3010 Roll axis 3011 Tilt axis 3013 Camera unit 3014 Slot 3020 Gimbal

Claims (11)

Lens system,
In order from the object side, a positive first lens group, an aperture stop, and a positive second lens group,
The first lens group includes a negative first lens whose image side surface is a concave surface facing the image side, and a positive second lens,
The second lens group includes a positive third lens having an image side surface whose convex surface faces the image side, a negative fourth lens, a positive fifth lens, and a negative sixth lens,
The material of the second lens is glass, and the material of the first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens is plastic,
f1 is the focal length of the first lens, f3-6 is the focal length of the second lens group, Nd2 is the refractive index of the second lens at the d line, and Vd2 is the Abbe number of the second lens at the d line. Formula −0.12<1/f1+1/f3-6<0.12
Nd2> 1.65
Vd2> 30
Satisfied,
Where f2 is the focal length of the second lens, f3 is the focal length of the third lens, and f is the focal length of the entire lens system, the conditional expression 0.9 <f2/f <1.7.
0.4 <f3/f <1.4
A lens system that satisfies the requirements. Lens system,
In order from the object side, a positive first lens group, an aperture stop, and a positive second lens group,
The first lens group includes a negative first lens whose image side surface is a concave surface facing the image side, and a positive second lens,
The second lens group includes a positive third lens having an image side surface whose convex surface faces the image side, a negative fourth lens, a positive fifth lens, and a negative sixth lens,
The material of the second lens is glass, and the material of the first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens is plastic,
f1 is the focal length of the first lens, f3-6 is the focal length of the second lens group, Nd2 is the refractive index of the second lens at the d line, and Vd2 is the Abbe number of the second lens at the d line. formula
−0.12<1/f1+1/f3-6<0.12
Nd2> 1.65
Vd2> 30
Satisfied,
f2 is the focal length of the second lens, f is the focal length of the entire lens system, and TT is the total length of the lens system, the conditional expression
0.9 <f2/f <1.7
1.5 <TT/f <3.5
A lens system that satisfies the requirements. Lens system,
In order from the object side, a positive first lens group, an aperture stop, and a positive second lens group,
The first lens group includes a negative first lens whose image side surface is a concave surface facing the image side, and a positive second lens,
The second lens group includes a positive third lens having an image side surface whose convex surface faces the image side, a negative fourth lens, a positive fifth lens, and a negative sixth lens,
The material of the second lens is glass, and the material of the first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens is plastic,
f1 is the focal length of the first lens, f3-6 is the focal length of the second lens group, Nd2 is the refractive index of the second lens at the d line, and Vd2 is the Abbe number of the second lens at the d line. Formula −0.12<1/f1+1/f3-6<0.12
Nd2> 1.65
Vd2> 30
Satisfied,
f2 is the focal length of the second lens, f3 is the focal length of the third lens, and f is the focal length of the entire lens system. Conditional expression 1.051 ≤ f2/f <1.7
0.4 <f3/f <1.4
A lens system that satisfies the requirements. Lens system,
In order from the object side, a positive first lens group, an aperture stop, and a positive second lens group,
The first lens group includes a negative first lens whose image side surface is a concave surface facing the image side, and a positive second lens,
The second lens group includes a positive third lens having an image side surface whose convex surface faces the image side, a negative fourth lens, a positive fifth lens, and a negative sixth lens,
The material of the second lens is glass, and the material of the first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens is plastic,
f1 is the focal length of the first lens, f3-6 is the focal length of the second lens group, Nd2 is the refractive index of the second lens at the d-line, and Vd2 is the Abbe number of the second lens at the d-line. formula
−0.12<1/f1+1/f3-6<0.12
Nd2> 1.65
Vd2> 30
Satisfied,
f2 is the focal length of the second lens, f is the focal length of the entire lens system, and TT is the total length of the lens system, the conditional expression
1.051 ≤ f2/f <1.7
1.5 <TT/f <3.5
A lens system that satisfies the requirements. Lens system,
In order from the object side, a positive first lens group, an aperture stop, and a positive second lens group,
The first lens group includes a negative first lens whose image side surface is a concave surface facing the image side, and a positive second lens,
The second lens group includes a positive third lens having an image side surface whose convex surface faces the image side, a negative fourth lens, a positive fifth lens, and a negative sixth lens,
The material of the second lens is glass, and the material of the first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens is plastic,
f1 is the focal length of the first lens, f3-6 is the focal length of the second lens group, Nd2 is the refractive index of the second lens at the d line, and Vd2 is the Abbe number of the second lens at the d line. Formula −0.12<1/f1+1/f3-6<0.12
Nd2> 1.65
Vd2> 30
Satisfied,
Where f is the focal length of the entire lens system and f3 is the focal length of the third lens , conditional expression 0.6<f3-6/f≦1.759
0.4 <f3/f <1.4
A lens system that satisfies the requirements. Lens system,
In order from the object side, a positive first lens group, an aperture stop, and a positive second lens group,
The first lens group includes a negative first lens whose image side surface is a concave surface facing the image side, and a positive second lens,
The second lens group includes a positive third lens having an image side surface whose convex surface faces the image side, a negative fourth lens, a positive fifth lens, and a negative sixth lens,
The material of the second lens is glass, and the material of the first lens, the third lens, the fourth lens, the fifth lens, and the sixth lens is plastic,
f1 is the focal length of the first lens, f3-6 is the focal length of the second lens group, Nd2 is the refractive index of the second lens at the d-line, and Vd2 is the Abbe number of the second lens at the d-line. formula
-0.12 <1/f1+1/f3-6 <0.12
Nd2> 1.65
Vd2> 30
Satisfied,
where f is the focal length of the entire lens system and TT is the total length of the lens system, a conditional expression
0.6 <f3-6/f ≤ 1.759
1.5 <TT/f <3.5
A lens system that satisfies the requirements. Conditional expression 0.7<f2/f<1.7 where f2 is the focal length of the second lens.
The lens system according to claim 5 or 6 , which satisfies: Conditional expression 0.6<f3-6/f<2.3
The lens system according to any one of claims 1 to 4, which satisfies the above condition. A lens system according to any one of claims 1 to 8 ,
An imaging device including an imaging element. A movable body that moves with the lens system according to any one of claims 1 to 8. The moving body according to claim 10 , wherein the moving body is an unmanned aerial vehicle.

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