JP2023541982A - optical device - Google Patents

Abstract

An optical device is provided, the optical device including a lens group including a plurality of lenses, a moving unit configured to move the plurality of lenses, and controlling the moving unit to move the plurality of lenses closest to each other. The control unit is configured to switch between a closed position state in which the lens functions as one lens and an open position state in which the plurality of lenses are arranged apart from each other.

Description

TECHNICAL FIELD The present disclosure relates to optical apparatus, devices, and methods for controlling the refractive power of lens groups within an optical apparatus. For example, the device may be a mobile device such as a mobile phone, smart phone, tablet computer, or personal computer. Optionally, the device may be a digital still camera, digital video camera, security/surveillance camera, network camera, automotive/traffic camera, medical camera, or the like.

2. Description of the Related Art Conventionally, as a method for realizing a zoom function and a focus function in an imaging device, there is a method of changing the refractive power by relatively moving the lenses in a lens group including a plurality of lenses. It is also known to change the refractive power by changing and controlling the curvature of a single lens using a liquid lens.

On the other hand, the miniaturization of imaging devices contributes to the miniaturization of mobile devices equipped with imaging functions, such as smartphones, mobile phones, tablets, and drive recorders. Moreover, the miniaturization also contributes to the miniaturization of imaging devices such as web cameras, action cameras, monitoring cameras, and compact digital cameras. Furthermore, the imaging device can be further downsized by suppressing an increase in the size of the entire lens group forming the imaging lens.

The present disclosure makes it possible to change the distribution of refractive power while suppressing an increase in the size of the lens group.

Under the above circumstances, technical advantages are provided by the embodiments disclosed below. Embodiments provide optical apparatus, devices, and methods for controlling the optical power of lens groups within an optical apparatus. The device may be a mobile phone, smart phone, tablet computer, personal computer, digital still camera, digital video camera, security/surveillance camera, network camera, automotive/traffic camera, medical camera, or the like.

A first aspect of an embodiment provides an optical device.

In a first possible implementation of the first aspect, the optical device includes a lens group including a plurality of lenses, a movement unit configured to move the plurality of lenses, and a movement unit configured to control the movement unit to move the plurality of lenses. a control unit configured to switch between a closed position state in which the lenses are closest together and function as one lens, and an open position state in which the plurality of lenses are spaced apart from each other. According to a first implementation of the first aspect, the refractive power of the lens group is switched between a first refractive power corresponding to a closed position state and a second refractive power corresponding to an open position state. It can be done.

A second possible implementation of the first aspect provides an apparatus according to the first possible implementation of the first aspect.

Here, in the closed position state, the plurality of lenses are configured to satisfy the condition given by the following equation (1).
_Dmin /φ<0.2...(1)
Here, D _min indicates the distance between two adjacent lenses in the lens group, and φ indicates the optical effective diameter of the lens having the largest lens diameter in the lens group.
Optionally, the plurality of lenses in the closed position state may satisfy the following condition given by equation (1a) below.
_Dmin /φ<0.1...(1a)

A third possible implementation of the first aspect provides an apparatus according to the first or second possible implementation of the first aspect. Here, the plurality of lenses include first and second aspheric lenses facing each other, and the image side surface of the first lens and the object side surface of the second lens facing the image side surface of the first lens. The side surface has a shape expressed by the following equations (2) and (3).
0.5<abs[S _оb (h)/S _im (h)]<2.0...(2)
Here, S _оb (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis, and S _im (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis. Indicates the amount of sag on the image side surface.
0.7<R _оb /R _im <1.3...(3)
Here, R _оb represents the radius of curvature of the object-side surface of the second lens, and R _im represents the radius of curvature of the image-side surface of the first lens.

Optionally, the image side surface of the first lens and the object side surface of the second lens opposite the image side surface of the first lens are expressed by equations (2a) and (3a) below. It may have the shape of
0.7<abs[S _оb (h)/S _im (h)]<1.8...(2a)
0.8<R _оb /R _im <1.2...(3a)

Optionally, the image-side surface of the first lens and the object-side surface of the second lens opposite the image-side surface of the first lens have a shape represented by equation (3b) below. may have.
0.7<abs[S _оb (h)/S _im (h)]<1.6...(3b)

A second aspect of the embodiments provides a device.

In a first possible implementation of the second aspect, the device includes an optical device, an image sensor for receiving light passing through the optical device, and a processor for generating image data based on an output signal from the image sensor. The optical device includes a lens group including a plurality of lenses, a movement unit configured to move the plurality of lenses, and a movement unit configured to control the movement unit so that the plurality of lenses come closest to one lens. and a control unit configured to switch between a closed position in which the lens functions as a lens, and an open position in which the plurality of lenses are spaced apart from each other. According to a first implementation of the first aspect, the refractive power of the lens group is switched between a first refractive power corresponding to a closed position state and a second refractive power corresponding to an open position state. It can be done.

A second possible implementation of the second aspect provides a device according to the first possible implementation of the second aspect. Here, in the closed position state, the plurality of lenses are configured to satisfy the condition given by the following equation (1).
_Dmin /φ<0.2...(1)
Here, D _min indicates the distance between two adjacent lenses in the lens group, and φ indicates the optical effective diameter of the lens having the largest lens diameter in the lens group.
Optionally, the plurality of lenses in the closed position state may satisfy the condition given by equation (1a) below.
_Dmin /φ<0.1...(1a)

A third possible implementation of the second aspect provides a device according to the first or second possible implementation of the second aspect. Here, the plurality of lenses include first and second aspheric lenses facing each other, and the image side surface of the first lens and the object side surface of the second lens facing the image side surface of the first lens. The side surface has a shape expressed by the following equations (2) and (3).
0.5<abs[S _оb (h)/S _im (h)]<2.0...(2)
Here, S _оb (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis, and S _im (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis. Indicates the amount of sag on the image side surface.
0.7<R _оb /R _im <1.3...(3)
Here, R _оb represents the radius of curvature of the object-side surface of the second lens, and R _im represents the radius of curvature of the image-side surface of the first lens.

Optionally, the image side surface of the first lens and the object side surface of the second lens opposite the image side surface of the first lens are expressed by equations (2a) and (3a) below. It may have the shape of
0.7<abs[S _оb (h)/S _im (h)]<1.8...(2a)
0.8<R _оb /R _im <1.2...(3a)

Optionally, the image-side surface of the first lens and the object-side surface of the second lens opposite the image-side surface of the first lens have a shape represented by equation (3b) below. may have.
0.7<abs[S _оb (h)/S _im (h)]<1.6...(3b)

A third aspect of the embodiments provides a method. According to a first possible implementation of the third aspect, there is provided a method for controlling the optical power of a lens group including a plurality of lenses, the method comprising the steps of: The method includes moving the plurality of lenses to switch between a closed position in which the lenses function as one lens and an open position in which the plurality of lenses are spaced apart from each other. According to the first implementation of the third aspect, the refractive power of the lens group is switched between a first refractive power corresponding to a closed position state and a second refractive power corresponding to an open position state. It can be done.

A second possible implementation of the second aspect provides a method according to the first possible implementation of the third aspect. Here, in the closed position state, the plurality of lenses are configured to satisfy the condition given by the following equation (1).
_Dmin /φ<0.2...(1)
Here, D _min indicates the distance between two adjacent lenses in the lens group, and φ indicates the optical effective diameter of the lens having the largest lens diameter in the lens group.
Optionally, the plurality of lenses in the closed position state may satisfy the condition given by equation (1a) below.
_Dmin /φ<0.1...(1a)

A fourth aspect of the embodiments provides a non-transitory computer-readable storage medium storing a program for causing a processor to perform a method according to the first or second possible implementation of the third aspect. A fifth aspect of the embodiment provides a computer readable program for causing a processor to perform a method according to the first or second possible implementation of the third aspect.

FIG. 7 is an external view showing an example of the hardware configuration of a mobile device that can mount the imaging lens group according to each of the first to sixth embodiments. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1; FIG. 7 is a block diagram showing an example of the hardware configuration of a mobile device that can implement the imaging lens group according to each of the first to sixth embodiments. FIG. 4A is a configuration diagram showing an example of the imaging lens according to the first embodiment. FIG. 4B is a table showing the focal length of each lens constituting the imaging lens group according to the first embodiment and conditions satisfied by the lens. 3 is a table showing lens parameters of each lens constituting the imaging lens group according to the first embodiment. FIG. 6A is a configuration diagram showing an example of an imaging lens group according to the second embodiment. FIG. 6B is a table showing the focal length of each lens constituting the imaging lens group according to the second embodiment and the conditions satisfied by the lens. It is a table showing lens parameters of each lens that constitutes the imaging lens group according to the second embodiment. FIG. 8A is a configuration diagram showing an example of an imaging lens group according to the third embodiment. FIG. 8B is a table showing the focal length of each lens constituting the imaging lens group according to the third embodiment and the conditions satisfied by the lens. FIG. 9 is a table showing lens parameters of each lens making up the imaging lens group according to the third embodiment. FIG. 10A is a configuration diagram showing an example of an imaging lens group according to the fourth embodiment. FIG. 10B is a table showing the focal length of each lens constituting the imaging lens group according to the fourth embodiment and the conditions satisfied by the lens. 12 is a table showing lens parameters of each lens constituting the imaging lens group according to the fourth embodiment. FIG. 12A is a configuration diagram showing an example of an imaging lens group according to the fifth embodiment. FIG. 12B is a table showing the focal length of each lens constituting the imaging lens group according to the fifth embodiment and the conditions satisfied by the lens. 12 is a table showing lens parameters of each lens constituting the imaging lens group according to the fifth embodiment. FIG. 14A is a configuration diagram showing an example of an imaging lens group according to the sixth embodiment. FIG. 6B is a table showing the focal length of each lens constituting the imaging lens group according to the sixth embodiment and the conditions satisfied by the lens. It is a table showing lens parameters of each lens that constitutes the imaging lens group according to the sixth embodiment. 3 is a table showing lens data of each lens constituting an imaging lens group according to each embodiment.

In the following, technical solutions of embodiments will be described with reference to the accompanying drawings. The embodiments described below are obviously only some, but not all, of the embodiments according to the present disclosure. It should be noted that all other embodiments that can be obtained without creative efforts by a person skilled in the art based on the embodiments described below should also fall within the protection scope of the embodiments of the present disclosure.

Below, a configuration example of a mobile device that can implement the imaging lens group according to each embodiment will be described first, and then the first embodiment, the second embodiment, the third embodiment, the fourth embodiment, and the fifth embodiment will be described. A configuration example of the imaging lens group according to the sixth embodiment and characteristics of the imaging lenses will be sequentially described.

(Example of implementation on mobile device)
With reference to FIGS. 1 to 3, a mobile device 10 including one of imaging lens groups 101, 102, 103, 104, 105, and 106 of first to sixth embodiments to be described later will be described. The mobile device 10 illustrated in FIGS. 1 and 2 is a smartphone, but is not limited thereto. Mobile device 10 is an example of a device according to embodiments of the present disclosure. For example, the device may be a mobile phone, smart phone, tablet computer, personal computer, digital still camera, digital video camera, security/surveillance camera, network camera, automotive/traffic camera, medical camera, or the like.

FIG. 1 is a perspective view showing the external configuration of a smartphone 10 that can be equipped with an imaging lens group according to each of the first to sixth embodiments. In this configuration example, the smartphone includes three imaging units 31, 32, and 33. It should be noted that FIG. 1 only shows the openings of each of the three imaging units arranged in the case member 20 of the smartphone 10.

FIG. 2 is a sectional view taken along the line II-II in FIG. As shown in FIG. 2, the imaging unit 31 of the smartphone 10 includes a main lens 15 forming an opening of the imaging unit 31, and an imaging lens group ( (lens unit) 11 and an imaging device 16. During imaging, light entering through the main lens 15 serving as an aperture passes through each element in the above order and reaches the imaging device 16. Further, the imaging unit 31 includes a moving unit 120 for moving the imaging lens group 11, which will be described later in the section of each embodiment, and the moving unit 120 includes an actuator 12 (FIG. 3) as a driving source thereof. .

The imaging device 16 includes an imaging element 170 such as a CCD or CMOS, and an AD conversion circuit (not shown) that converts an analog electrical signal output from the imaging element into a digital imaging signal.

The imaging element 170 of the imaging device 16 is arranged at the position of the imaging plane. The image sensor has multiple pixels. For example, the image sensor includes a pixel that generates an electrical signal corresponding to the intensity of the red light component, a pixel that generates an electrical signal that corresponds to the intensity of the blue light component, and a pixel that generates an electrical signal that corresponds to the intensity of the green light component. Contains pixels. As a modification, the image sensor may be another image sensor for monochrome photography that includes a plurality of pixels that generate electrical signals corresponding to the intensity of light.

FIG. 3 is a block diagram showing an example of a hardware configuration of a smartphone 10 that can be equipped with an imaging lens according to each of the first to sixth embodiments, and mainly shows a control configuration related to an imaging unit 31.

As shown in FIG. 3, the control configuration of the smartphone 10 includes an actuator 12, a driver 13, and a CPU 14.

The CPU 14 executes a program stored in a memory (not shown) to control the movement of lenses in lens groups described later in the first to sixth embodiments. Specifically, the CPU 14 controls the drive of the actuator 12 via the driver 13, thereby controlling the movement of each lens in the imaging lens group 11. Actuator 12 and driver 13 may be examples of moving units according to embodiments of the present disclosure, and CPU 14 may be examples of control units according to embodiments of this disclosure. Further, the set of the imaging lens group 11, the actuator 12, and the driver 13 may be an example of the optical device according to the embodiment of the present disclosure. The configuration described above allows for moving and positioning the lenses in the lens groups of each embodiment described below.

Below, first to sixth embodiments of the imaging lens group 11 in the smartphone 10 will be described.

(First embodiment)

4A and 4B are diagrams showing an imaging lens group 101 according to the first embodiment of the present disclosure that can be installed as the imaging lens group 11 shown in the configuration example of the smartphone 10. 4A shows the lens positions of the imaging lens group 101 at the closed position and the open position, respectively, and FIG. 4B shows a table showing the focal lengths and the like of the imaging lens group 101 at the closed position and the open position. As shown in FIG. 4A, the imaging lens group 101 of this embodiment includes three lenses L1 to L3. Further, AX represents the optical axis, and S1, S2, S3, S4, S5, and S6 represent the surfaces of the lenses L1 to L3, respectively. Regarding the imaging lens group 101, the closed position is a position where each lens approaches each other and conditional expressions (1) to (3) described below are satisfied. The open position is a position where each lens of the imaging lens group 101 is spaced apart from each other so as to achieve a predetermined refractive power. This makes it possible to reverse the positive and negative refractive powers given in the closed position and the open position. Also, the open position can be determined, for example, to provide a refractive power that corresponds to the zoom and focus functions of the imaging device. Therefore, in a system of one lens group, the combination of distances D1 and D2 between the lenses, which will be described later with reference to FIG. There may be multiple open positions depending on the

In FIG. 4A, lenses L1, L2, and L3 of the imaging lens group 101 are arranged in order from the object side, which is the left side of FIG. 4A, to the image side, which is the right side of FIG. 4A. That is, the lens L1 is located closest to the object side, and the lens L3 is located closest to the image side.

As shown in FIG. 4A, surfaces S1 and S2 are aspheric surfaces that achieve predetermined optical properties. The shape of surfaces S1 and S2 allows lens L1 to have positive refractive power.

Lens L2 is an aspherical lens. The shape of surfaces S3 and S4 allows lens L2 to have negative refractive power.

The object-side surface S5 of the lens L3 has a shape similar to the image-side surface S4 of the adjacent lens L2 in the closed position, and is an aspheric surface that achieves predetermined optical characteristics. The shape of surfaces S5 and S6 allows lens L3 to have negative refractive power.

As shown in the table of FIG. 4B, the focal lengths of lenses L1, L2, and L3 in this embodiment are 22.8, -324.27, and -19.92, respectively. The total focal length of the entire imaging lens group 101 in the closed position and the open position is 29.14 and 23.94, respectively. Surface conditions indicating the degree of approximation of lens surface shapes that are close to each other in the closed position are S2/S3 of 0.84 and S4/S5 of 1.04. Similarly, the radius conditions indicating the degree of approximation of the lens surface shapes that are close to each other in the closed position are 1.19 for S2/S3 and 0.96 for S4/S5. The distance condition shown in FIG. 4B is a parameter of conditional expression (1) described later, and indicates the distance between the lenses when they are closest to each other in the closed position. In the imaging lens group 101 of this embodiment, the distance condition is 0.003.

In the closed position, lenses L1, L2, and L3 are close to each other and satisfy conditional expressions (1) to (3) described below. Then, in this state (positional relationship), the three lenses L1, L2, and L3 have the same refractive power as one lens in the entire lens group. On the other hand, in the open position, lenses L1, L2, and L3 are separated from each other. In this state (positional relationship), the lenses L1, L2, and L3 have their respective refractive powers, but the imaging lens group 101 as a whole has a refractive power different from that in the open position.

As described above, in the closed position, lenses L1, L2, and L3 of the imaging lens group 101 are close to each other, and the entire lens group has the same refractive power as a single lens. On the other hand, in the open position, the refractive powers of each lens are combined, so that the entire imaging lens group 101 has a different refractive power than in the closed position. Then, when the lenses L1, L2, and L3 are set to the closed position and the open position in terms of positional (distance) relationship, it becomes possible to generate a refractive power distribution according to that relationship.

Here, conditional expressions (1) to (3) that must be satisfied in order for the lenses L1, L2, and L3 of the imaging lens group 101 to produce the above-mentioned refractive power distribution in the closed position will be described.

Lenses L1, L2, and L3 of the imaging lens group 10 are
D _min /φ < 0.2 …Conditional expression (1)
is satisfied, D _min is the lens distance between each lens when the lenses L1, L2, and L3 are close to each other in the closed position, and φ is the distance between the lenses L1, L2, and L3 that constitute the imaging lens group 101. This is the optical effective diameter of the lens with the largest lens diameter. In this embodiment, the lens distance is a value given by the distance conditions shown in FIG. 4B.
Furthermore, the lens surfaces of lenses L1, L2, and L3 that face each other have similar surface shapes that satisfy the following conditional expression (2), and S _оb (h) is S im (h) is the surface shape (sag amount) of the object side surface, and S _im (h) is the surface shape (sag amount) of the image side surface. In this embodiment, the surface shape has a value given by the surface conditions shown in FIG. 4B.
0.5 < abs[S _оb (h)/S _im (h)] < 2.0...Conditional expression (2)
The radii of curvature R ₁ and R ₂ , R ₃ and R ₄ , and R ₅ and R ₆ of the lens surfaces facing each other satisfy the following conditional expressions, and R _оb is the radius of curvature of the object-side surface facing the object. , and R _im is the radius of curvature of the image side surface. In this embodiment, those radii of curvature have values given by the radius conditions shown in FIG. 4B.
0.7 < R _оb /R _im < 1.3 ... Conditional expression (3)

More suitable conditions will be provided below for conditional expressions (1) to (3). In conditional expression (1), when the value of D _min /φ becomes 0.2 or more, the refractive power of each lens begins to affect each lens individually, and even when each lens is in the closed position, the entire lens group is approximately unified. This makes it difficult to use it as a lens. As a result, the difference when switching between the power arrangement of refractive power in the closed position and the power arrangement of refractive power after the lens is separated becomes smaller, making it impossible to obtain the expected effect. Therefore, conditional expression (1) is
D _min /φ < 0.1 ... Conditional expression (4)
It is preferable that

Furthermore, when the surface shape of the lens does not satisfy conditional expressions (2) and (3), the lens surfaces of lenses L1, L2, and L3 that face each other are affected by their own refractive action, so that each lens Even in the closed position, it becomes difficult to treat the entire lens group approximately as a single lens. As a result, the difference when switching between the power arrangement of refractive power in the closed position and the power arrangement of refractive power after the lens is separated becomes smaller, making it impossible to obtain the expected effect. Therefore, conditional expressions (2) and (3) are each more preferably
0.7 < abs[S _оb (h)/S _im (h)] < 1.8...Conditional expression (5)
as well as,
0.8 < R _оb /R _im < 1.2... Conditional expression (6)
Should be.

Furthermore, conditional expression (5) is more preferably
0.7 < abs[S _оb (h)/S _im (h)] < 1.6...Conditional expression (7)
Should be.

Next, conditions regarding parameters that define the optical characteristics of lenses L1, L2, and L3 included in the imaging lens group 101 will be described with reference to FIG. 5. RDN in FIG. 5 indicates parameters such as each surface S1 to S6 of each lens constituting the imaging lens group 101 according to the first embodiment, R is the radius of curvature of the lens surface, and D is the distance between each lens. Nd is the refractive index on each surface, Vd is the Abbe number, and φ is the effective optical diameter of each lens. Here, D1 represents the distance between the image side (S2) of lens L1 and the object side (S3) of lens L2, and D2 represents the distance between the image side (S4) of lens L2 and the object side of lens L3. (S5), and D1 and D2 show different values depending on whether the lens group is in the closed position or in the open position. Specifically, as shown in FIG. 5, in the closed position, D1 is 0.01 and D2 is 0.01, and in the open position, D1 is 1.23 and D2 is 1.69.

“Aspherical Coefficients” in FIG. 5 indicates the aspherical coefficients of the corresponding order.

Among the parameters shown in the RDN table of FIG. 5, R, D, Nd, and φ are designed to satisfy all of the above-mentioned conditional expressions (1) to (3). The Abbe number Vd is a value that corrects longitudinal chromatic aberration and lateral chromatic aberration in a well-balanced manner.

The shape of the aspherical lens is given by the aspherical shape formula shown in equation (8) below, where Z represents the depth of the aspherical surface, and Y is the distance from the optical axis to the lens surface. (height), R represents the paraxial radius of curvature, K represents the conic constant, and C ₄ , C ₆ , C ₈ , and C ₁₀ represent the 4th, 6th, 8th, and 10th orders, respectively. represents the aspheric coefficient of

Z=(Y ² /R)/[1-{1-(1+K)(Y ² /R ² )} ^1/2 ]+C ₄ Y ⁴ +C ₆ Y ⁶ +C ₈ Y ⁸ +C ₁₀ Y ¹⁰ …conditional expression (8)

In the example shown in FIG. 5, the lens L2 is an aspherical lens. Lenses L1 and L3 have an aspherical surface on one side and a spherical surface on the other side. At least one of the lenses L1, L2, and L3 may be a resin lens. For example, when the aspherical lens is composed of a resin lens that can be easily processed, the manufacturing cost of the imaging lens group 101 can be reduced.

Comparing the total focal length of the lens group in the closed position and the open position in the table shown in FIG. 4B, it is 29.14 mm in the closed position and 23.94 mm in the open position. Therefore, by changing the state from the closed position to the open position and changing the refractive power distribution, it is possible for the three lenses L1, L2, and L3 to have a zoom lens function.

In addition, the values in the table shown in Figure 4B representing the values of conditional expressions (1) to (3) satisfy conditional expressions (4) to (6) that provide more suitable conditions, and provide more suitable conditions. It is understood that the provided conditional expression (7) is also satisfied. As a result, lenses L1, L2, L3 in this embodiment behave as a single lens in the entire lens group in the closed position, and during separation to the open position, the lenses are Furthermore, the refractive power distribution of the entire lens group can be changed from the value at the closed position.
As mentioned above, when a plurality of lenses are arranged to form a lens group and their arrangement relationship does not satisfy conditional expressions (1) to (3), the plurality of lenses exist individually, and each lens is simply It merely realizes the optical properties of. On the other hand, according to the first embodiment of the present disclosure, the arrangement relationship of the plurality of lenses is set so that conditional expressions (1) to (3) are satisfied in the closed position, and the lenses have a predetermined refractive power in the open position. Be prepared. Thereby, the lens, as a lens group, can produce a refractive power distribution according to the positional relationship of the lenses. As a result, it is possible to prevent the size of the imaging device from increasing when the refractive power distribution is realized.

(Second embodiment)
Next, a second embodiment will be described. In the following, detailed explanations of contents that overlap with those of the first embodiment will be omitted.

6A and 6B are diagrams showing an imaging lens group 102 according to a second embodiment of the present disclosure, which can be implemented as the imaging lens group 11 shown in the configuration example of the smartphone 10. 6A shows the lens positions of the imaging lens group 102 at the closed position and the open position, and FIG. 6B shows a table showing the focal lengths of the imaging lens group 102 at the closed position and the open position.

In FIG. 6A, lenses L1, L2, L3, and L4 of the imaging lens group 102 according to the second embodiment are arranged in order from the object side, which is the left side of FIG. 6A, to the image side, which is the right side of FIG. 6A. That is, the lens L1 is located closest to the object side, and the lens L4 is located closest to the image side.

The shapes of lenses L1, L2, L3, and L4 are as shown in FIG. 6A. In the imaging lens group 102, lenses L1 and L2 have negative refractive power. Lenses L3 and L4 have positive refractive power. Lens L3 is an aspherical lens.

Each lens of the imaging lens group 102 satisfies the conditions shown in FIG. 6B, and its shape is defined by the lens parameters shown in FIG. 7.

FIG. 7 is a table showing lens parameters of each lens making up the imaging lens group 102 according to the second embodiment. FIG. 6B shows the focal lengths of the lenses constituting the imaging lens group 102 according to the second embodiment, the total focal length of the entire lens group at the open position and the closed position, and the conditional expressions for the lenses L1, L2, L3, and L4. It is a table showing each value of (1) to (3).

By setting the lens parameters of each lens according to the conditions shown in FIG. 6B, various aberrations can be corrected. Further, since the Abbe number of each lens is set as shown in FIG. 7, chromatic aberration can be corrected. Also, when comparing the total focal length in the closed position and the open position, the total focal length in the open position is 58.82 mm, and the total focal length in the closed position is 341.42 mm, which is the same as that in the open position. This is approximately 5.8 times the total focal length. Therefore, the four lenses L1, L2, L3, and L4 of the imaging lens group 102 can have the function of a zoom lens by changing the state from the closed position to the open position and changing the refractive power distribution.

As shown in FIG. 6A, lenses L1 and L2, lenses L2 and L3, and lenses L3 and L4 have similar shapes at least in the vicinity of the optical axis with respect to opposing sides S2 and S3, S4 and S5, and S6 and S7, respectively. . As a result, the lenses in the closed position can approach each other so as to satisfy conditional expressions (1) to (3) and have a refractive power equivalent to that of a single lens.

(Third embodiment)
Next, a third embodiment will be described. In the following, detailed explanations of contents that overlap with those of the first embodiment will be omitted.

8A and 8B are diagrams showing an imaging lens group 103 according to a third embodiment of the present disclosure, which can be implemented as the imaging lens group 11 shown in the configuration example of the smartphone 10. 8A shows the positions of the lenses in the closed and open positions of the imaging lens group 103, and FIG. 8B shows a table showing the focal lengths and the like of the imaging lens group 103 in the closed and open positions. The lens configuration of the imaging lens group 103 corresponds to the conditions shown in FIG. 8B and the lens parameters shown in FIG. 9, which will be described later.

As shown in FIG. 8A, the imaging lens group 103 of this embodiment includes two lenses L1 and L2. The lenses L1 and L2 are arranged in order from the object side, which is the left side of FIG. 8A, to the image side, which is the right side of FIG. 8A. Lens L1 is located closest to the object side, and lens L2 is located closest to the image side.

The shapes of lenses L1 and L2 are as shown in FIG. 8A. In the imaging lens group 103, the lens L1 has negative refractive power. Lens L2 has positive refractive power. Lenses L1 and L2 are aspheric lenses.

Each lens of the imaging lens group 103 satisfies the conditions shown in FIG. 8B, and its shape is defined by the lens parameters shown in FIG. 9.

FIG. 8B shows the focal lengths of the lenses constituting the imaging lens group 103 according to the third embodiment, the total focal length of the entire lens group at the open position and the closed position, and conditional expressions (1) to 1 for the lenses L1 and L2. It is a table showing each value of (3). FIG. 9 is a table showing lens parameters of each lens making up the imaging lens group 103 according to the third embodiment.

By setting the lens parameters of each lens according to the conditions shown in FIG. 8B, various aberrations can be corrected. Furthermore, since the Abbe number of each lens is set as shown in FIG. 9, chromatic aberration can be corrected. Also, comparing the total focal length in the closed position and the open position, the total focal length in the open position is 13.48 mm, and the total focal length in the closed position is 89.97 mm, which is the same as that in the open position. This is approximately 6.7 times the total focal length. Therefore, the two lenses L1 and L2 of the imaging lens group 103 can have the function of a zoom lens by changing the state from the closed position to the open position and changing the refractive power distribution.

As shown in FIG. 8A, the lenses L1 and L2 have shapes that are similar to each other at least in the vicinity of the optical axis on opposing surfaces S2 and S3. As a result, the lenses in the closed position can approach each other so as to satisfy conditional expressions (1) to (3) and have a refractive power equivalent to that of a single lens.

(Fourth embodiment)
Next, a fourth embodiment will be described. In the following, detailed explanations of contents that overlap with those of the first embodiment will be omitted.

10A and 10B are diagrams showing an imaging lens group 104 according to a fourth embodiment of the present disclosure, which can be implemented as the imaging lens group 11 shown in the configuration example of the smartphone 10. FIG. 10A shows the lens positions of the imaging lens group 104 at the closed position and the open position, and FIG. 10B shows a table showing the focal lengths of the imaging lens group 104 at the closed position and the open position.

As shown in FIG. 10A, the imaging lens group 104 of this embodiment includes two lenses L1 and L2. Lenses L1 and L2 are arranged in order from the object side, which is the left side of FIG. 10A, to the image side, which is the right side of FIG. 10A. Lens L1 is located closest to the object side, and lens L2 is located closest to the image side.

The shapes of lenses L1 and L2 are as shown in FIG. 10A. In the imaging lens group 104, the lens L1 has negative refractive power. Lens L2 has positive refractive power. Lens L1 is an aspherical lens.

Each lens of the imaging lens group 104 satisfies the conditions shown in FIG. 10B, and its shape is defined by the lens parameters shown in FIG. 11.

FIG. 10B shows the focal lengths of the lenses constituting the imaging lens group 104 according to the fourth embodiment, the total focal length of the entire lens group at the open position and the closed position, and conditional expressions (1) to 1 for the lenses L1 and L2. It is a table showing each value of (3). FIG. 11 is a table showing lens parameters of each lens making up the imaging lens group 104 according to the fourth embodiment.

By setting the lens parameters of each lens according to the conditions shown in FIG. 10B, various aberrations can be corrected. Furthermore, since the Abbe number of each lens is set as shown in FIG. 11, chromatic aberration can be corrected. Also, when comparing the total focal length in the closed position and the open position, the total focal length in the closed position takes a negative value of -60.40mm, and the total focal length in the open position takes a positive value of 50.20mm. . Therefore, the two lenses L1 and L2 of the imaging lens group 104 can have the function of a zoom lens by changing the state from the closed position to the open position and changing the refractive power distribution from negative to positive.

As shown in FIG. 10A, opposite sides S2 and S3 of lenses L1 and L2 are close to each other with a slight spacing between them in the closed position. However, even in this case, the lenses L1 and L2 satisfy conditional expressions (1) to (3), so that the lenses in the closed position have the same refractive power as a single lens.

(Fifth embodiment)
Next, a fifth embodiment will be described. In the following, detailed explanations of contents that overlap with those of the first embodiment will be omitted.

12A and 12B are diagrams showing an imaging lens group 105 according to a fifth embodiment of the present disclosure, which can be implemented as the imaging lens group 11 shown in the configuration example of the smartphone 10. 12A shows the positions of the lenses in the closed and open positions of the imaging lens group 105, and FIG. 12B shows a table showing the focal lengths and the like of the imaging lens group 105 in the closed and open positions.

As shown in FIG. 12A, the imaging lens group 105 of this embodiment includes three lenses L1 to L3. Lenses L1, L2, and L3 are arranged in order from the object side, which is the left side of FIG. 12A, to the image side, which is the right side of FIG. 12A. Lens L1 is located closest to the object side, and lens L3 is located closest to the image side.

The shapes of lenses L1, L2, and L3 are as shown in FIG. 12A. In the imaging lens group 105, lenses L1 and L3 have negative refractive power. Lens L3 is an aspherical lens. Lens L2 has positive refractive power.

Each lens of the imaging lens group 105 satisfies the conditions shown in FIG. 12B, and its shape is defined by the lens parameters shown in FIG. 13.

FIG. 12B shows the focal lengths of the lenses constituting the imaging lens group 105 according to the fifth embodiment, the total focal length of the entire lens group at the open position and the closed position, and the conditional expression (1 ) to (3). FIG. 13 is a table showing lens parameters of each lens making up the imaging lens group 105 according to the fifth embodiment.

By setting the lens parameters of each lens according to the conditions shown in FIG. 12B, various aberrations can be corrected. Furthermore, since the Abbe number of each lens is set as shown in FIG. 13, chromatic aberration can be corrected. Also, when comparing the total focal length in the closed position and the open position, the total focal length in the closed position takes a negative value of -60.40mm, and the total focal length in the open position takes a positive value of 50.20mm. . Therefore, the three lenses L1, L2, and L3 of the imaging lens group 105 can have the function of a zoom lens by changing the state from the closed position to the open position and changing the refractive power distribution from negative to positive. can.

As shown in FIG. 12A, lenses L1 and L2 have shapes that are similar at least near the optical axis on opposing sides S2 and S3, respectively. The same applies to L2 and L3. As a result, the lenses in the closed position can approach each other so as to satisfy conditional expressions (1) to (3) and have a refractive power equivalent to that of a single lens.

(Sixth embodiment)
Next, a sixth embodiment will be described. In the following, detailed explanations of contents that overlap with those of the first embodiment will be omitted.

14A and 14B are diagrams showing an imaging lens group 106 according to a sixth embodiment of the present disclosure, which can be implemented as the imaging lens group 11 shown in the configuration example of the smartphone 10. FIG. 14A shows the positions of the lenses in the closed and open positions of the imaging lens group 106, and FIG. 14B shows a table showing the focal lengths and the like of the imaging lens group 106 in the closed and open positions.

As shown in FIG. 14A, the imaging lens group 106 of this embodiment includes three lenses L1 to L3. Lenses L1, L2, and L3 are arranged in order from the object side, which is the left side of FIG. 14A, to the image side, which is the right side of FIG. 14A. Lens L1 is located closest to the object side, and lens L3 is located closest to the image side.

The shapes of lenses L1, L2, and L3 are as shown in FIG. 14A. In the imaging lens group 106, lenses L1 and L2 have negative refractive power. Lenses L1, L2, and L3 are aspheric lenses. Lens L3 has positive refractive power.

Each lens of the imaging lens group 106 satisfies the conditions shown in FIG. 14B, and its shape is defined by the lens parameters shown in FIG. 15.

FIG. 14B shows the focal lengths of the lenses constituting the imaging lens group 106 according to the sixth embodiment, the total focal length of the entire lens group at the open position and the closed position, and the conditional expression (1 ) to (3). FIG. 15 is a table showing lens parameters of each lens making up the imaging lens group 106 according to the sixth embodiment.

By setting the lens parameters of each lens according to the conditions shown in FIG. 14B, various aberrations can be corrected. Furthermore, since the Abbe number of each lens is set as shown in FIG. 15, chromatic aberration can be corrected. Also, when comparing the total focal length in the closed position and the open position, the total focal length in the closed position takes a negative value of -60.40mm, and the total focal length in the open position takes a positive value of 50.20mm. . Therefore, the three lenses L1, L2, and L3 of the imaging lens group 106 can have the function of a zoom lens by changing the state from the closed position to the open position and changing the refractive power distribution from negative to positive. can.

As shown in FIG. 14A, opposite sides S3, S4, S5 of lenses L1, L2, L3 have a small spacing between them in the closed position. However, even in this case, lenses L1, L2, and L3 satisfy conditional expressions (1) to (3), so that the lenses in the closed position have a refractive power equivalent to that of a single lens.

In FIG. 16, the values of conditional expressions (1) to (3) for each example are summarized. As can be understood from the values in the table, conditional expressions (1) to (3) are satisfied in each example. Furthermore, since conditional expressions (4) to (6) and (7) are satisfied in Example 1, Example 2, and Example 3, the imaging lenses constituting Example 1, Example 2, and Example 3 are more suitable. has parameters.

The above disclosure merely discloses exemplary embodiments and is not intended to limit the protection scope of the present invention. Those skilled in the art will understand that all or part of the embodiments described above and other embodiments and modifications that can be derived based on the scope of the claims of the present invention naturally fall within the scope of the present invention. Dew.

TECHNICAL FIELD The present disclosure relates to optical apparatus, devices, and methods for controlling the refractive power of lens groups within an optical apparatus. For example, the device may be a mobile device such as a mobile phone, smart phone, tablet computer, or personal computer. Optionally, the device may be a digital still camera, digital video camera, security/surveillance camera, network camera, automotive/traffic camera, medical camera, or the like.

2. Description of the Related Art Conventionally, as a method for realizing a zoom function and a focus function in an imaging device, there is a method of changing the refractive power by relatively moving the lenses in a lens group including a plurality of lenses. It is also known to change the refractive power by changing and controlling the curvature of a single lens using a liquid lens.

On the other hand, the miniaturization of imaging devices contributes to the miniaturization of mobile devices equipped with imaging functions, such as smartphones, mobile phones, tablets, and drive recorders. Moreover, the miniaturization also contributes to the miniaturization of imaging devices such as web cameras, action cameras, monitoring cameras, and compact digital cameras. Furthermore, the imaging device can be further downsized by suppressing an increase in the size of the entire lens group forming the imaging lens.

The present disclosure makes it possible to change the distribution of refractive power while suppressing an increase in the size of the lens group.

Under the above circumstances, technical advantages are provided by the embodiments disclosed below. Embodiments provide optical apparatus, devices, and methods for controlling the optical power of lens groups within an optical apparatus. The device may be a mobile phone, smart phone, tablet computer, personal computer, digital still camera, digital video camera, security/surveillance camera, network camera, automotive/traffic camera, medical camera, or the like.

A first aspect of an embodiment provides an optical device.

In a first possible implementation of the first aspect, the optical device includes a lens group including a plurality of lenses, a movement unit configured to move the plurality of lenses, and a movement unit configured to control the movement unit to move the plurality of lenses. a control unit configured to switch between a closed position state in which the lenses are closest together and function as one lens, and an open position state in which the plurality of lenses are spaced apart from each other. According to a first possible implementation of the first aspect, the optical power of the lens group is between a first optical power corresponding to the closed position state and a second optical power corresponding to the open position state. It can be switched with .

A second possible implementation of the first aspect provides an apparatus according to the first possible implementation of the first aspect.

Here, in the closed position state, the plurality of lenses are configured to satisfy the condition given by the following equation (1).
_Dmin /φ<0.2...(1)
Here, D _min indicates the distance between two adjacent lenses in the lens group, and φ indicates the optical effective diameter of the lens having the largest lens diameter in the lens group.
Optionally, the plurality of lenses in the closed position state may satisfy the condition given by equation (1a) below.
_Dmin /φ<0.1...(1a)

A third possible implementation of the first aspect provides an apparatus according to the first or second possible implementation of the first aspect. Here, the plurality of lenses include first and second aspheric lenses facing each other, and the image side surface of the first lens and the object side surface of the second lens facing the image side surface of the first lens. The side surface has a shape expressed by the following equations (2) and (3).
0.5<abs[S _оb (h)/S _im (h)]<2.0...(2)
Here, S _оb (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis, and S _im (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis. Indicates the amount of sag on the image side surface.
0.7<R _оb /R _im <1.3...(3)
Here, R _оb represents the radius of curvature of the object-side surface of the second lens, and R _im represents the radius of curvature of the image-side surface of the first lens.

Optionally, the image side surface of the first lens and the object side surface of the second lens opposite the image side surface of the first lens are expressed by equations (2a) and (3a) below. It may have the shape of
0.7<abs[S _оb (h)/S _im (h)]<1.8...(2a)
0.8<R _оb /R _im <1.2...(3a)

Optionally, the image-side surface of the first lens and the object-side surface of the second lens opposite the image-side surface of the first lens have a shape represented by equation (3b) below. may have.
0.7<abs[S _оb (h)/S _im (h)]<1.6...(3b)

A second aspect of the embodiments provides a device.

In a first possible implementation of the second aspect, the device includes an optical device, an image sensor for receiving light passing through the optical device, and a processor for generating image data based on an output signal from the image sensor. The optical device includes a lens group including a plurality of lenses, a movement unit configured to move the plurality of lenses, and a movement unit configured to control the movement unit so that the plurality of lenses come closest to one lens. and a control unit configured to switch between a closed position in which the lens functions as a lens, and an open position in which the plurality of lenses are spaced apart from each other. According to a first possible implementation of the second aspect, the optical power of the lens group is between a first optical power corresponding to the closed position state and a second optical power corresponding to the open position state. It can be switched with .

A second possible implementation of the second aspect provides a device according to the first possible implementation of the second aspect. Here, in the closed position state, the plurality of lenses are configured to satisfy the condition given by the following equation (1).
_Dmin /φ<0.2...(1)
Here, D _min indicates the distance between two adjacent lenses in the lens group, and φ indicates the optical effective diameter of the lens having the largest lens diameter in the lens group.
Optionally, the plurality of lenses in the closed position state may satisfy the condition given by equation (1a) below.
_Dmin /φ<0.1...(1a)

A third possible implementation of the second aspect provides a device according to the first or second possible implementation of the second aspect. Here, the plurality of lenses include first and second aspheric lenses facing each other, and the image side surface of the first lens and the object side surface of the second lens facing the image side surface of the first lens. The side surface has a shape expressed by the following equations (2) and (3).
0.5<abs[S _оb (h)/S _im (h)]<2.0...(2)
Here, S _оb (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis, and S _im (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis. Indicates the amount of sag on the image side surface.
0.7<R _оb /R _im <1.3...(3)
Here, R _оb represents the radius of curvature of the object-side surface of the second lens, and R _im represents the radius of curvature of the image-side surface of the first lens.

Optionally, the image side surface of the first lens and the object side surface of the second lens opposite the image side surface of the first lens are expressed by equations (2a) and (3a) below. It may have the shape of
0.7<abs[S _оb (h)/S _im (h)]<1.8...(2a)
0.8<R _оb /R _im <1.2...(3a)

Optionally, the image-side surface of the first lens and the object-side surface of the second lens opposite the image-side surface of the first lens have a shape represented by equation (3b) below. may have.
0.7<abs[S _оb (h)/S _im (h)]<1.6...(3b)

A third aspect of the embodiments provides a method for controlling the refractive power of a lens group including a plurality of lenses . According to a first possible implementation of the third aspect , the method is characterized in that the actuator provides a closed position state in which the plurality of lenses are closest together and act as one lens; and moving the plurality of lenses to switch between open and open positions. According to a first possible implementation of the third aspect, the optical power of the lens group is between a first optical power corresponding to the closed position condition and a second optical power corresponding to the open position condition. It can be switched with .

A second possible implementation of the third aspect provides a method according to the first possible implementation of the third aspect. Here, in the closed position state, the plurality of lenses are configured to satisfy the condition given by the following equation (1).
_Dmin /φ<0.2...(1)
Here, D _min indicates the distance between two adjacent lenses in the lens group, and φ indicates the optical effective diameter of the lens having the largest lens diameter in the lens group.
Optionally, the plurality of lenses in the closed position state may satisfy the condition given by equation (1a) below.
_Dmin /φ<0.1...(1a)

A fourth aspect of the embodiments provides a non-transitory computer-readable storage medium storing a program for causing a processor to perform a method according to the first or second possible implementation of the third aspect. A fifth aspect of the embodiment provides a computer readable program for causing a processor to perform a method according to the first or second possible implementation of the third aspect.

FIG. 7 is an external view showing an example of the hardware configuration of a mobile device that can mount the imaging lens group according to each of the first to sixth embodiments. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1; FIG. 7 is a block diagram showing an example of the hardware configuration of a mobile device that can implement the imaging lens group according to each of the first to sixth embodiments. FIG. 4(a) is a configuration diagram showing an example of the imaging lens according to the first embodiment. FIG. 4(b) is a table showing the focal length of each lens constituting the imaging lens group according to the first embodiment and the conditions satisfied by the lens. 3 is a table showing lens parameters of each lens constituting the imaging lens group according to the first embodiment. FIG. 6A is a configuration diagram showing an example of an imaging lens group according to the second embodiment. FIG. 6(b) is a table showing the focal length of each lens constituting the imaging lens group according to the second embodiment and the conditions satisfied by the lens. It is a table showing lens parameters of each lens that constitutes the imaging lens group according to the second embodiment. FIG. 8A is a configuration diagram showing an example of an imaging lens group according to the third embodiment. FIG. 8(b) is a table showing the focal length of each lens constituting the imaging lens group according to the third embodiment and the conditions satisfied by the lens. FIG. 9 is a table showing lens parameters of each lens making up the imaging lens group according to the third embodiment. FIG. 10A is a configuration diagram showing an example of an imaging lens group according to the fourth embodiment. FIG. 10(b) is a table showing the focal length of each lens constituting the imaging lens group according to the fourth embodiment and the conditions satisfied by the lenses. 12 is a table showing lens parameters of each lens constituting the imaging lens group according to the fourth embodiment. FIG. 12A is a configuration diagram showing an example of an imaging lens group according to the fifth embodiment. FIG. 12(b) is a table showing the focal length of each lens constituting the imaging lens group according to the fifth embodiment and the conditions satisfied by the lens. 12 is a table showing lens parameters of each lens constituting the imaging lens group according to the fifth embodiment. FIG. 14A is a configuration diagram showing an example of an imaging lens group according to the sixth embodiment. FIG. 14(b) is a table showing the focal length of each lens constituting the imaging lens group according to the sixth embodiment and the conditions satisfied by the lens. 12 is a table showing lens parameters of each lens constituting the imaging lens group according to the sixth embodiment. 3 is a table showing lens data of each lens constituting an imaging lens group according to each embodiment.

In the following, technical solutions of embodiments will be described with reference to the accompanying drawings. The embodiments described below are obviously only some, but not all, of the embodiments according to the present disclosure. It should be noted that all other embodiments that can be obtained without creative efforts by a person skilled in the art based on the embodiments described below should also fall within the protection scope of the embodiments of the present disclosure.

Below, a configuration example of a mobile device that can implement the imaging lens group according to each embodiment will be described first, and then the first embodiment, the second embodiment, the third embodiment, the fourth embodiment, and the fifth embodiment will be described. A configuration example of the imaging lens group according to the sixth embodiment and characteristics of the imaging lenses will be sequentially described.

(Example of implementation on mobile device)
With reference to FIGS. 1 to 3, a mobile device 10 that can be equipped with one of imaging lens groups 101, 102, 103, 104, 105, and 106 of first to sixth embodiments to be described later will be described. The mobile device 10 illustrated in FIGS. 1 and 2 is a smartphone, but is not limited thereto. Mobile device 10 is an example of a device according to embodiments of the present disclosure. For example, the device may be a mobile phone, smart phone, tablet computer, personal computer, digital still camera, digital video camera, security/surveillance camera, network camera, automotive/traffic camera, medical camera, or the like.

FIG. 1 is a perspective view showing the external configuration of a smartphone 10 that can be equipped with an imaging lens group according to each of the first to sixth embodiments. In this configuration example, the smartphone includes three imaging units 31, 32, and 33. It should be noted that FIG. 1 only shows the openings of each of the three imaging units arranged in the case member 20 of the smartphone 10.

FIG. 2 is a sectional view taken along the line II-II in FIG. As shown in FIG. 2, the imaging unit 31 of the smartphone 10 includes a main lens 15 forming an opening of the imaging unit 31, and an imaging lens group ( (lens unit) 11 and an imaging device 16. During imaging, light entering through the main lens 15 serving as an aperture passes through each element in the above order and reaches the imaging device 16. Further, the imaging unit 31 includes a moving unit 120 for moving the imaging lens group 11, which will be described later in the section of each embodiment, and the moving unit 120 includes an actuator 12 (FIG. 3) as a driving source thereof. .

The imaging device 16 includes an imaging element 170 such as a CCD or CMOS, and an AD conversion circuit (not shown) that converts an analog electrical signal output from the imaging element into a digital imaging signal.

The imaging element 170 of the imaging device 16 is arranged at the position of the imaging plane. The image sensor has multiple pixels. For example, the image sensor includes a pixel that generates an electric signal corresponding to the intensity of the red light component, a pixel that generates an electric signal that corresponds to the intensity of the blue light component, and a pixel that generates an electric signal that corresponds to the intensity of the green light component. Contains pixels. As a modification, the image sensor may be another image sensor for monochrome photography that includes a plurality of pixels that generate electrical signals corresponding to the intensity of light.

FIG. 3 is a block diagram showing an example of a hardware configuration of a smartphone 10 that can be equipped with an imaging lens according to each of the first to sixth embodiments, and mainly shows a control configuration related to an imaging unit 31.

As shown in FIG. 3, the control configuration of the smartphone 10 includes an actuator 12, a driver 13, and a CPU 14.

The CPU 14 executes a program stored in a memory (not shown) to control the movement of lenses in lens groups described later in the first to sixth embodiments. Specifically, the CPU 14 controls the drive of the actuator 12 via the driver 13, thereby controlling the movement of each lens in the imaging lens group 11. Actuator 12 and driver 13 may be examples of moving units according to embodiments of the present disclosure, and CPU 14 may be examples of control units according to embodiments of this disclosure. Further, the set of the imaging lens group 11, the actuator 12, and the driver 13 may be an example of the optical device according to the embodiment of the present disclosure. The configuration described above allows for moving and positioning the lenses in the lens groups of each embodiment described below.

Below, first to sixth embodiments of the imaging lens group 11 in the smartphone 10 will be described.

(First embodiment)

FIGS. 4A and 4B are diagrams showing an imaging lens group 101 according to the first embodiment of the present disclosure that can be installed as the imaging lens group 11 shown in the configuration example of the smartphone 10. 4(a) shows the lens positions of the imaging lens group 101 in the closed position and the open position, respectively, and FIG. 4(b) shows the focal length etc. of the imaging lens group 101 in the closed position and the open position, respectively. Shows a table showing. As shown in FIG. 4(a) , the imaging lens group 101 of this embodiment includes three lenses L1 to L3. Further, AX represents the optical axis, and S1, S2, S3, S4, S5, and S6 represent the surfaces of the lenses L1 to L3, respectively. Regarding the imaging lens group 101, the closed position is a position where each lens approaches each other and conditional expressions (1) to (3) described below are satisfied. The open position is a position where each lens of the imaging lens group 101 is spaced apart from each other so as to achieve a predetermined refractive power. This makes it possible to reverse the positive and negative refractive powers given in the closed position and the open position. Also, the open position can be determined, for example, to provide a refractive power that corresponds to the zoom and focus functions of the imaging device. Therefore, in a system of one lens group, the combination of distances D1 and D2 between the lenses, which will be described later with reference to FIG. There may be multiple open positions depending on the

In FIG. 4(a) , lenses L1, L2, and L3 of the imaging lens group 101 are arranged in order from the object side, which is the left side of FIG. 4(a) , to the image side, which is the right side of FIG. 4(a) . That is, the lens L1 is located closest to the object side, and the lens L3 is located closest to the image side.

As shown in FIG. 4(a) , surfaces S1 and S2 are aspheric surfaces that achieve predetermined optical characteristics. The shape of surfaces S1 and S2 allows lens L1 to have positive refractive power.

Lens L2 is an aspherical lens. The shape of surfaces S3 and S4 allows lens L2 to have negative refractive power.

The object-side surface S5 of the lens L3 has a shape similar to the image-side surface S4 of the adjacent lens L2 in the closed position, and is an aspheric surface that achieves predetermined optical characteristics. The shape of surfaces S5 and S6 allows lens L3 to have negative refractive power.

As shown in the table of FIG. 4(b) , the focal lengths of lenses L1, L2, and L3 in this embodiment are 22.8, -324.27, and -19.92, respectively. The total focal length of the entire imaging lens group 101 in the closed position and the open position is 29.14 and 23.94, respectively. Surface conditions indicating the degree of approximation of lens surface shapes that are close to each other in the closed position are S2/S3 of 0.84 and S4/S5 of 1.04. Similarly, the radius conditions indicating the degree of approximation of the lens surface shapes that are close to each other in the closed position are 1.19 for S2/S3 and 0.96 for S4/S5. The distance condition shown in FIG. 4(b) is a parameter of conditional expression (1) described later, and indicates the distance between the lenses when they are closest to each other in the closed position. In the imaging lens group 101 of this embodiment, the distance condition is 0.003.

In the closed position, lenses L1, L2, and L3 are close to each other and satisfy conditional expressions (1) to (3) described below. Then, in this state (positional relationship), the three lenses L1, L2, and L3 have the same refractive power as one lens in the entire lens group. On the other hand, in the open position, lenses L1, L2, and L3 are separated from each other. In this state (positional relationship), the lenses L1, L2, and L3 have their respective refractive powers, but the imaging lens group 101 as a whole has a refractive power different from that in the open position.

As described above, in the closed position, lenses L1, L2, and L3 of the imaging lens group 101 are close to each other, and the entire lens group has the same refractive power as a single lens. On the other hand, in the open position, the refractive powers of each lens are combined, so that the entire imaging lens group 101 has a different refractive power than in the closed position. Then, when the lenses L1, L2, and L3 are set to the closed position and the open position in terms of positional (distance) relationship, it becomes possible to generate a refractive power distribution according to that relationship.

Here, conditional expressions (1) to (3) that must be satisfied in order for the lenses L1, L2, and L3 of the imaging lens group 101 to produce the above-mentioned refractive power distribution in the closed position will be described.

Lenses L1, L2, and L3 of the imaging lens group 10 are
D _min /φ < 0.2 …Conditional expression (1)
is satisfied, D _min is the lens distance between each lens when the lenses L1, L2, and L3 are close to each other in the closed position, and φ is the distance between the lenses L1, L2, and L3 that constitute the imaging lens group 101. This is the optical effective diameter of the lens with the largest lens diameter. In this embodiment, the lens distance is a value given by the distance conditions shown in FIG. 4(b) .
Furthermore, the lens surfaces of lenses L1, L2, and L3 that face each other have similar surface shapes that satisfy the following conditional expression (2), and S _оb (h) is S im (h) is the surface shape (sag amount) of the object side surface, and S _im (h) is the surface shape (sag amount) of the image side surface. In this embodiment, the surface shape has a value given by the surface conditions shown in FIG. 4(b) .
0.5 < abs[S _оb (h)/S _im (h)] < 2.0...Conditional expression (2)
The radii of curvature R ₁ and R ₂ , R ₃ and R ₄ , and R ₅ and R ₆ of the lens surfaces facing each other satisfy the following conditional expressions, and R _оb is the radius of curvature of the object-side surface facing the object. , and R _im is the radius of curvature of the image side surface. In this embodiment, those radii of curvature have values given by the radius conditions shown in FIG. 4(b) .
0.7 < R _оb /R _im < 1.3 ... Conditional expression (3)

More suitable conditions will be provided below for conditional expressions (1) to (3). In conditional expression (1), when the value of D _min /φ becomes 0.2 or more, the refractive power of each lens begins to affect each lens individually, and even when each lens is in the closed position, the entire lens group is approximately unified. This makes it difficult to use it as a lens. As a result, the difference when switching between the power arrangement of refractive power in the closed position and the power arrangement of refractive power after the lens is separated becomes smaller, making it impossible to obtain the expected effect. Therefore, conditional expression (1) is
D _min /φ < 0.1 ... Conditional expression (4)
It is preferable that

Furthermore, when the surface shape of the lens does not satisfy conditional expressions (2) and (3), the lens surfaces of lenses L1, L2, and L3 that face each other are affected by their own refractive action, so that each lens Even in the closed position, it becomes difficult to treat the entire lens group approximately as a single lens. As a result, the difference when switching between the power arrangement of refractive power in the closed position and the power arrangement of refractive power after the lens is separated becomes smaller, making it impossible to obtain the expected effect. Therefore, conditional expressions (2) and (3) are each more preferably
0.7 < abs[S _оb (h)/S _im (h)] < 1.8...Conditional expression (5)
as well as,
0.8 < R _оb /R _im < 1.2... Conditional expression (6)
Should be.

Furthermore, conditional expression (5) is more preferably
0.7 < abs[S _оb (h)/S _im (h)] < 1.6...Conditional expression (7)
Should be.

Next, conditions regarding parameters that define the optical characteristics of lenses L1, L2, and L3 included in the imaging lens group 101 will be described with reference to FIG. 5. RDN in FIG. 5 indicates parameters such as each surface S1 to S6 of each lens constituting the imaging lens group 101 according to the first embodiment, R is the radius of curvature of the lens surface, and D is the distance between each lens. Nd is the refractive index on each surface, Vd is the Abbe number, and φ is the effective optical diameter of each lens. Here, D1 represents the distance between the image side (S2) of lens L1 and the object side (S3) of lens L2, and D2 represents the distance between the image side (S4) of lens L2 and the object side of lens L3. (S5), and D1 and D2 show different values depending on whether the lens group is in the closed position or in the open position. Specifically, as shown in FIG. 5, in the closed position, D1 is 0.01 and D2 is 0.01, and in the open position, D1 is 1.23 and D2 is 1.69.

“Aspherical Coefficients” in FIG. 5 indicates the aspherical coefficients of the corresponding order.

Among the parameters shown in the RDN table of FIG. 5, R, D, Nd, and φ are designed to satisfy all of the above-mentioned conditional expressions (1) to (3). The Abbe number Vd is a value that corrects longitudinal chromatic aberration and lateral chromatic aberration in a well-balanced manner.

The shape of the aspherical lens is given by the aspherical shape formula shown in equation (8) below, where Z represents the depth of the aspherical surface, and Y is the distance from the optical axis to the lens surface. (height), R represents the paraxial radius of curvature, K represents the conic constant, and C ₄ , C ₆ , C ₈ , and C ₁₀ represent the 4th, 6th, 8th, and 10th orders, respectively. represents the aspheric coefficient of

Z=(Y ² /R)/[1-{1-(1+K)(Y ² /R ² )} ^1/2 ]+C ₄ Y ⁴ +C ₆ Y ⁶ +C ₈ Y ⁸ +C ₁₀ Y ¹⁰ …conditional expression (8)

In the example shown in FIG. 5, the lens L2 is an aspherical lens. Lenses L1 and L3 have an aspherical surface on one side and a spherical surface on the other side. At least one of the lenses L1, L2, and L3 may be a resin lens. For example, when the aspherical lens is composed of a resin lens that can be easily processed, the manufacturing cost of the imaging lens group 101 can be reduced.

Comparing the total focal length of the lens group at the closed position and the open position in the table shown in FIG. 4(b) , it is 29.14 mm at the closed position and 23.94 mm at the open position. Therefore, by changing the state from the closed position to the open position and changing the refractive power distribution, it is possible for the three lenses L1, L2, and L3 to have a zoom lens function.

In addition, the values in the table shown in FIG. 4(b) representing the values of conditional expressions (1) to (3) satisfy conditional expressions (4) to (6), which provide more suitable conditions, and are more suitable. It is understood that conditional expression (7), which provides the following conditions, is also satisfied. As a result, lenses L1, L2, L3 in this embodiment behave as a single lens in the entire lens group in the closed position, and during separation to the open position, the lenses are Furthermore, the refractive power distribution of the entire lens group can be changed from the value at the closed position.
As mentioned above, when a plurality of lenses are arranged to form a lens group and their arrangement relationship does not satisfy conditional expressions (1) to (3), the plurality of lenses exist individually, and each lens is simply It merely realizes the optical properties of. On the other hand, according to the first embodiment of the present disclosure, the arrangement relationship of the plurality of lenses is set so that conditional expressions (1) to (3) are satisfied in the closed position, and the lenses have a predetermined refractive power in the open position. Be prepared. Thereby, the lens, as a lens group, can produce a refractive power distribution according to the positional relationship of the lenses. As a result, it is possible to prevent the size of the imaging device from increasing when the refractive power distribution is realized.

(Second embodiment)
Next, a second embodiment will be described. In the following, detailed explanations of contents that overlap with those of the first embodiment will be omitted.

FIGS. 6A and 6B are diagrams showing an imaging lens group 102 according to a second embodiment of the present disclosure, which can be implemented as the imaging lens group 11 shown in the configuration example of the smartphone 10. 6(a) shows the lens positions of the imaging lens group 102 in the closed position and the open position, and FIG. 6(b) shows the focal length etc. of the imaging lens group 102 in the closed position and the open position. Show the table.

In FIG. 6(a) , lenses L1, L2, L3, and L4 of the imaging lens group 102 according to the second embodiment are arranged from the object side, which is the left side of FIG. 6(a) , to the image side, which is the right side of FIG. 6(a). are arranged in order from side to side. That is, the lens L1 is located closest to the object side, and the lens L4 is located closest to the image side.

The shapes of the lenses L1, L2, L3, and L4 are as shown in FIG. 6(a) . In the imaging lens group 102, lenses L1 and L2 have negative refractive power. Lenses L3 and L4 have positive refractive power. Lens L3 is an aspherical lens.

Each lens of the imaging lens group 102 satisfies the conditions shown in FIG. 6(b) , and its shape is defined by the lens parameters shown in FIG. 7.

FIG. 7 is a table showing lens parameters of each lens making up the imaging lens group 102 according to the second embodiment. FIG. 6(b) shows the focal lengths of the lenses constituting the imaging lens group 102 according to the second embodiment, the total focal length of the entire lens group at the open position and the closed position, and the lenses L1, L2, L3, and L4. This is a table showing each value of conditional expressions (1) to (3).

Various aberrations can be corrected by setting the lens parameters of each lens according to the conditions shown in FIG. 6(b) . Further, since the Abbe number of each lens is set as shown in FIG. 7, chromatic aberration can be corrected. Also, when comparing the total focal length in the closed position and the open position, the total focal length in the open position is 58.82 mm, and the total focal length in the closed position is 341.42 mm, which is the same as that in the open position. This is approximately 5.8 times the total focal length. Therefore, the four lenses L1, L2, L3, and L4 of the imaging lens group 102 can have the function of a zoom lens by changing the state from the closed position to the open position and changing the refractive power distribution.

As shown in FIG. 6(a) , lenses L1 and L2, lenses L2 and L3, and lenses L3 and L4 are approximated at least near the optical axis with respect to opposing sides S2 and S3, S4 and S5, and S6 and S7, respectively. It has a shape. As a result, the lenses in the closed position can approach each other so as to satisfy conditional expressions (1) to (3) and have a refractive power equivalent to that of a single lens.

(Third embodiment)
Next, a third embodiment will be described. In the following, detailed explanations of contents that overlap with those of the first embodiment will be omitted.

FIGS. 8A and 8B are diagrams showing an imaging lens group 103 according to a third embodiment of the present disclosure, which can be implemented as the imaging lens group 11 shown in the configuration example of the smartphone 10. 8(a) shows the lens positions of the imaging lens group 103 in the closed position and the open position, and FIG. 8(b) shows the focal length etc. of the imaging lens group 103 in the closed position and the open position. Show the table. The lens configuration of the imaging lens group 103 corresponds to the conditions shown in FIG. 8(b) and the lens parameters shown in FIG. 9, which will be described later.

As shown in FIG. 8(a) , the imaging lens group 103 of this embodiment includes two lenses L1 and L2. The lenses L1 and L2 are arranged in order from the object side, which is the left side of FIG. 8(a) , to the image side, which is the right side of FIG. 8(a) . Lens L1 is located closest to the object side, and lens L2 is located closest to the image side.

The shapes of the lenses L1 and L2 are as shown in FIG. 8(a) . In the imaging lens group 103, the lens L1 has negative refractive power. Lens L2 has positive refractive power. Lenses L1 and L2 are aspheric lenses.

Each lens of the imaging lens group 103 satisfies the conditions shown in FIG. 8(b) , and its shape is defined by the lens parameters shown in FIG. 9.

FIG. 8(b) shows the focal lengths of the lenses constituting the imaging lens group 103 according to the third embodiment, the total focal length of the entire lens group at the open position and the closed position, and the conditional expression ( 1) is a table showing each value of (3). FIG. 9 is a table showing lens parameters of each lens making up the imaging lens group 103 according to the third embodiment.

Various aberrations can be corrected by setting the lens parameters of each lens according to the conditions shown in FIG. 8(b) . Furthermore, since the Abbe number of each lens is set as shown in FIG. 9, chromatic aberration can be corrected. Also, comparing the total focal length in the closed position and the open position, the total focal length in the open position is 13.48 mm, and the total focal length in the closed position is 89.97 mm, which is the same as that in the open position. This is approximately 6.7 times the total focal length. Therefore, the two lenses L1 and L2 of the imaging lens group 103 can have the function of a zoom lens by changing the state from the closed position to the open position and changing the refractive power distribution.

As shown in FIG. 8A , the lenses L1 and L2 have shapes that are similar to each other at least in the vicinity of the optical axis with respect to opposing surfaces S2 and S3. As a result, the lenses in the closed position can approach each other so as to satisfy conditional expressions (1) to (3) and have a refractive power equivalent to that of a single lens.

(Fourth embodiment)
Next, a fourth embodiment will be described. In the following, detailed explanations of contents that overlap with those of the first embodiment will be omitted.

FIGS. 10A and 10B are diagrams showing an imaging lens group 104 according to a fourth embodiment of the present disclosure, which can be implemented as the imaging lens group 11 shown in the configuration example of the smartphone 10. 10(a) shows the lens positions of the imaging lens group 104 in the closed position and the open position, and FIG. 10(b) shows the focal length etc. of the imaging lens group 104 in the closed position and the open position. Show the table.

As shown in FIG. 10(a) , the imaging lens group 104 of this embodiment includes two lenses L1 and L2. The lenses L1 and L2 are arranged in order from the object side, which is the left side of FIG. 10(a) , to the image side, which is the right side of FIG. 10(a) . Lens L1 is located closest to the object side, and lens L2 is located closest to the image side.

The shapes of the lenses L1 and L2 are as shown in FIG. 10(a) . In the imaging lens group 104, the lens L1 has negative refractive power. Lens L2 has positive refractive power. Lens L1 is an aspherical lens.

Each lens of the imaging lens group 104 satisfies the conditions shown in FIG. 10(b) , and its shape is defined by the lens parameters shown in FIG. 11.

FIG. 10(b) shows the focal lengths of the lenses constituting the imaging lens group 104 according to the fourth embodiment, the total focal length of the entire lens group at the open position and the closed position, and the conditional expression ( 1) is a table showing each value of (3). FIG. 11 is a table showing lens parameters of each lens making up the imaging lens group 104 according to the fourth embodiment.

Various aberrations can be corrected by setting the lens parameters of each lens according to the conditions shown in FIG. 10(b) . Furthermore, since the Abbe number of each lens is set as shown in FIG. 11, chromatic aberration can be corrected. Also, when comparing the total focal length in the closed position and the open position, the total focal length in the closed position takes a negative value of -60.40mm, and the total focal length in the open position takes a positive value of 50.20mm. . Therefore, the two lenses L1 and L2 of the imaging lens group 104 can have the function of a zoom lens by changing the state from the closed position to the open position and changing the refractive power distribution from negative to positive.

As shown in FIG. 10(a) , opposite sides S2 and S3 of lenses L1 and L2 are close to each other with a slight spacing between them in the closed position. However, even in this case, the lenses L1 and L2 satisfy conditional expressions (1) to (3), so that the lenses in the closed position have the same refractive power as a single lens.

(Fifth embodiment)
Next, a fifth embodiment will be described. In the following, detailed explanations of contents that overlap with those of the first embodiment will be omitted.

12(a) and 12(b) are diagrams showing an imaging lens group 105 according to a fifth embodiment of the present disclosure, which can be implemented as the imaging lens group 11 shown in the configuration example of the smartphone 10. 12(a) shows the lens positions of the imaging lens group 105 in the closed position and the open position, and FIG. 12(b) shows the focal length etc. of the imaging lens group 105 in the closed position and the open position. Show the table.

As shown in FIG. 12(a) , the imaging lens group 105 of this embodiment includes three lenses L1 to L3. Lenses L1, L2, and L3 are arranged in order from the object side, which is the left side of FIG. 12(a) , to the image side, which is the right side of FIG. 12(a) . Lens L1 is located closest to the object side, and lens L3 is located closest to the image side.

The shapes of the lenses L1, L2, and L3 are as shown in FIG. 12(a) . In the imaging lens group 105, lenses L1 and L3 have negative refractive power. Lens L3 is an aspherical lens. Lens L2 has positive refractive power.

Each lens of the imaging lens group 105 satisfies the conditions shown in FIG. 12(b) , and its shape is defined by the lens parameters shown in FIG. 13.

FIG. 12(b) shows the focal lengths of the lenses constituting the imaging lens group 105 according to the fifth embodiment, the total focal length of the entire lens group at the open position and the closed position, and the conditions for lenses L1, L2, and L3. 3 is a table showing each value of formulas (1) to (3). FIG. 13 is a table showing lens parameters of each lens making up the imaging lens group 105 according to the fifth embodiment.

By setting the lens parameters of each lens according to the conditions shown in FIG. 12(b) , various aberrations can be corrected. Furthermore, since the Abbe number of each lens is set as shown in FIG. 13, chromatic aberration can be corrected. Also, when comparing the total focal length in the closed position and the open position, the total focal length in the closed position takes a negative value of -60.40mm, and the total focal length in the open position takes a positive value of 50.20mm. . Therefore, the three lenses L1, L2, and L3 of the imaging lens group 105 can have the function of a zoom lens by changing the state from the closed position to the open position and changing the refractive power distribution from negative to positive. can.

As shown in FIG. 12(a) , the lenses L1 and L2 have shapes that are similar at least near the optical axis on opposing sides S2 and S3, respectively. The same applies to L2 and L3. As a result, the lenses in the closed position can approach each other so as to satisfy conditional expressions (1) to (3) and have a refractive power equivalent to that of a single lens.

(Sixth embodiment)
Next, a sixth embodiment will be described. In the following, detailed explanations of contents that overlap with those of the first embodiment will be omitted.

14(a) and 14(b) are diagrams showing an imaging lens group 106 according to a sixth embodiment of the present disclosure, which can be implemented as the imaging lens group 11 shown in the configuration example of the smartphone 10. 14(a) shows the lens positions of the imaging lens group 106 in the closed position and the open position, and FIG. 14(b) shows the focal length etc. of the imaging lens group 106 in the closed position and the open position. Show the table.

As shown in FIG. 14(a) , the imaging lens group 106 of this embodiment includes three lenses L1 to L3. Lenses L1, L2, and L3 are arranged in order from the object side, which is the left side of FIG. 14(a) , to the image side, which is the right side of FIG. 14(a) . Lens L1 is located closest to the object side, and lens L3 is located closest to the image side.

The shapes of the lenses L1, L2, and L3 are as shown in FIG. 14(a) . In the imaging lens group 106, lenses L1 and L2 have negative refractive power. Lenses L1, L2, and L3 are aspheric lenses. Lens L3 has positive refractive power.

Each lens of the imaging lens group 106 satisfies the conditions shown in FIG. 14(b) , and its shape is defined by the lens parameters shown in FIG. 15.

FIG. 14(b) shows the focal lengths of the lenses constituting the imaging lens group 106 according to the sixth embodiment, the total focal length of the entire lens group at the open position and the closed position, and the conditions for lenses L1, L2, and L3. 3 is a table showing each value of formulas (1) to (3). FIG. 15 is a table showing lens parameters of each lens making up the imaging lens group 106 according to the sixth embodiment.

Various aberrations can be corrected by setting the lens parameters of each lens according to the conditions shown in FIG. 14(b) . Furthermore, since the Abbe number of each lens is set as shown in FIG. 15, chromatic aberration can be corrected. Also, when comparing the total focal length in the closed position and the open position, the total focal length in the closed position takes a negative value of -60.40mm, and the total focal length in the open position takes a positive value of 50.20mm. . Therefore, the three lenses L1, L2, and L3 of the imaging lens group 106 can have the function of a zoom lens by changing the state from the closed position to the open position and changing the refractive power distribution from negative to positive. can.

As shown in FIG. 14(a) , opposite sides S3, S4, S5 of lenses L1, L2, L3 have a small spacing between them in the closed position. However, even in this case, lenses L1, L2, and L3 satisfy conditional expressions (1) to (3), so that the lenses in the closed position have a refractive power equivalent to that of a single lens.

In FIG. 16, the values of conditional expressions (1) to (3) for each example are summarized. As can be understood from the values in the table, conditional expressions (1) to (3) are satisfied in each example. Furthermore, since conditional expressions (4) to (6) and (7) are satisfied in Example 1, Example 2, and Example 3, the imaging lenses constituting Example 1, Example 2, and Example 3 are more suitable. has parameters.

The above disclosure merely discloses exemplary embodiments and is not intended to limit the protection scope of the present invention. Those skilled in the art will understand that all or part of the embodiments described above and other embodiments and modifications that can be derived based on the scope of the claims of the present invention naturally fall within the scope of the present invention. Dew.

Claims (16)

a lens group including multiple lenses;
a moving unit configured to move the plurality of lenses;
The moving unit is configured to control the moving unit to switch between a closed position state in which the plurality of lenses are closest to each other and function as one lens, and an open position state in which the plurality of lenses are arranged apart from each other. a control unit;
An optical device comprising: In the closed position state, the plurality of lenses are configured to satisfy the condition given by the following equation (1),
_Dmin /φ<0.2...(1)
Here, D _min indicates the distance between two adjacent lenses of the lens group, and φ indicates the optical effective diameter of the lens having the largest lens diameter in the lens group.
The device according to claim 1. The plurality of lenses include first and second aspheric lenses facing each other, the image-side surface of the first lens, and the second lens facing the image-side surface of the first lens. The object-side surface of has a shape expressed by the following equations (2) and (3),
0.5<abs[S _оb (h)/S _im (h)]<2.0...(2)
Here, S _оb (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis, and S _im (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis. Indicates the amount of sag on the image side surface of the first lens,
0.7<R _оb /R _im <1.3...(3)
Here, R _оb represents the radius of curvature of the object-side surface of the second lens, and R _im represents the radius of curvature of the image-side surface of the first lens.
The device according to claim 1 or 2. In the closed position state, the plurality of lenses are particularly configured to satisfy the condition given by the following equation (4),
_Dmin /φ<0.1...(4)
3. The device according to claim 2. In particular, the image-side surface of the first lens and the object-side surface of the second lens, which faces the image-side surface of the first lens, are defined by the following equation (5) and equation (6) configured to have a shape represented by
0.7<abs[S _оb (h)/S _im (h)]<1.8...(5)
0.8<R _оb /R _im <1.2...(6)
4. The device according to claim 3. The image-side surface of the first lens and the object-side surface of the second lens, which faces the image-side surface of the first lens, are particularly expressed by the following equation (7). configured to have a shape that
0.7<abs[S _оb (h)/S _im (h)]<1.6...(7)
Apparatus according to claim 5. A device comprising an optical device, an image sensor that receives light passing through the optical device, and a processor for generating image data based on an output signal from the image sensor, the optical device comprising:
a lens group including multiple lenses;
a moving unit configured to move the plurality of lenses;
The moving unit is configured to control the moving unit to switch between a closed position state in which the plurality of lenses are closest to each other and function as one lens, and an open position state in which the plurality of lenses are arranged apart from each other. a control unit;
A device comprising: In the closed position state, the plurality of lenses are configured to satisfy the condition given by the following equation (8),
_Dmin /φ<0.2...(8)
Here, D _min indicates the distance between two adjacent lenses of the lens group, and φ indicates the optical effective diameter of the lens having the largest lens diameter in the lens group.
8. A device according to claim 7. The plurality of lenses include first and second aspheric lenses facing each other, the image-side surface of the first lens, and the second lens facing the image-side surface of the first lens. The object-side surface of has a shape expressed by the following equations (9) and (10),
0.5<abs[S _оb (h)/S _im (h)]<2.0...(9)
Here, S _оb (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis, and S _im (h) represents the sag amount of the object side surface of the second lens at the height h from the optical axis. Indicates the amount of sag on the image side surface of the first lens,
0.7<R _оb /R _im <1.3...(10)
Here, R _оb represents the radius of curvature of the object-side surface of the second lens, and R _im represents the radius of curvature of the image-side surface of the first lens.
A device according to claim 7 or 8. In the closed position state, the plurality of lenses are particularly configured to satisfy the condition given by the following equation (11),
D _min /φ<0.1 (11)
9. A device according to claim 8. In particular, the image-side surface of the first lens and the object-side surface of the second lens, which faces the image-side surface of the first lens, are defined by the following equation (12) and equation (13) configured to have a shape expressed by
0.7<abs[S _оb (h)/S _im (h)]<1.8...(12)
0.8<R _оb /R _im <1.2 (13)
A device according to claim 9. The image-side surface of the first lens and the object-side surface of the second lens, which faces the image-side surface of the first lens, are particularly expressed by the following equation (14). configured to have a shape that
0.7<abs[S _оb (h)/S _im (h)]<1.6...(14)
The device according to claim 11. A method for controlling the refractive power of a lens group including a plurality of lenses, the method comprising:
The plurality of lenses are moved by an actuator so as to switch between a closed position state in which the plurality of lenses are closest to each other and function as one lens, and an open position state in which the plurality of lenses are arranged apart from each other. A method, including steps. The closed position state is configured such that the plurality of lenses satisfy the condition given by the following equation (15),
_Dmin /φ<0.2...(15)
Here, D _min indicates the distance between two adjacent lenses of the lens group, and φ indicates the optical effective diameter of the lens having the largest lens diameter in the lens group.
14. The method according to claim 13. The closed position state is particularly configured such that the plurality of lenses satisfy the condition given by the following equation (16),
_Dmin /φ<0.1...(16)
15. The method according to claim 14. A non-transitory computer-readable storage medium storing a program for causing a computer to execute the method according to any one of claims 13 to 15.

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