JP2019168491A - Wide-angle lens, lens unit, and image capturing device - Google Patents

Abstract

To provide a wide-angle lens which is compact and offers good optical performance.SOLUTION: A wide-angle lens 10 has a six-lens-configuration consisting of a front group G1, an aperture stop ST, and a rear group G2 in order from the object side, and satisfies the following conditional expression (1): |f/f1|<0.028 ...(1), where a value f1 represents a focal length of the front group G1, and a value f represents a focal length of the entire system.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a six-lens wide-angle lens including a front group, a stop, and a positive rear group, and a lens unit and an imaging apparatus including the wide-angle lens.

  In recent years, in-vehicle cameras and surveillance cameras have been required to have a wider angle, a smaller size, and a lower cost. In addition to the above demands, there is a demand for a lens that achieves high optical performance from on-axis to off-axis and maintains high performance even in harsh environments.

  The optical system described in Patent Document 1 is configured from a front group, a stop, and a positive rear group in order from the object side, thereby achieving a reduction in size and a wide angle. However, since the optical system of Patent Document 1 has too much power in the front group, a large curvature of field and lateral chromatic aberration are generated, and a sufficiently high optical performance cannot be achieved.

  Patent Document 1 proposes an optical system that uses an aspheric glass lens immediately after the aperture stop and an optical system in which all six lenses are made of plastic lenses. If aspherical glass is used as in the former case, it causes a significant increase in cost, and cost reduction cannot be achieved. In the case of an optical system that consists of all six plastic lenses, as in the latter case, plastic has a greater change in refractive index due to temperature changes than glass, so sufficient weather resistance cannot be ensured. The performance has been degraded.

Japanese Patent Laid-Open No. 2006-57562

  An object of the present invention is to provide a wide-angle lens that is compact and can ensure good optical performance.

  It is another object of the present invention to provide a lens unit and an imaging apparatus that include the wide-angle lens.

In order to achieve the above object, a wide-angle lens according to the present invention is a six-lens wide-angle lens including a front group, a stop, and a positive rear group in order from the object side, and satisfies the following conditional expression.
| f / f1 | <0.028 (1)
Here, the value f1 is the focal length of the front group, and the value f is the focal length of the entire system. The front group includes, for example, a first lens, a second lens, and a third lens. In this case, the rear group includes a fourth lens, a fifth lens, and a sixth lens. The present invention is not limited to the above, and the number of the six lenses distributed to the front group and the rear group can be changed.

The wide-angle lens includes, in order from the object side, a front group (for example, a first lens, a second lens, and a third lens), a diaphragm, and a positive rear group (for example, a fourth lens, a fifth lens, and a sixth lens). The lens arrangement is adopted, and widening can be achieved while reducing the diameter of the front lens. Conditional expression (1) defines the ratio of the focal length of the entire system to the focal length of the front group, and it is a feature of the present invention that the power of the front group is small. When the value f1 / f satisfies the conditional expression (1), the power of the front group does not become too large, the field curvature, coma aberration, and lateral chromatic aberration are suppressed, and high optical performance is achieved from on-axis to the periphery. Can do. In addition, since the power of the front group does not become too large, it is possible to suppress aberration fluctuations due to decentering errors during lens assembly. For conditional expression (1), the following range
| f / f1 | <0.025 (1) '
Is more desirable.

  In one specific aspect of the present invention, the lens disposed closest to the object side and the lens disposed immediately after the stop are glass lenses. For in-vehicle cameras and surveillance cameras, there is a demand for a lens that can be used in a wide temperature range with little performance degradation even under severe conditions. In the lens arranged closest to the object side, off-axis rays pass through a high position of the lens, which greatly affects off-axis performance. Further, both the on-axis light beam and off-axis light beam that pass through the lens arranged immediately after the stop are thick, and the influence on the on-axis and off-axis performance is great. By making these lenses into glass, the refractive index change due to temperature change is smaller than that of plastic, which suppresses spherical aberration and curvature of field variation due to temperature change, and from on-axis to the periphery even in harsh environments. High optical performance can be achieved. Furthermore, by using a material that is not easily damaged, such as glass, for the lens closest to the object in direct contact with the outside air, it is possible to prevent optical performance from being deteriorated due to the damage.

In another aspect of the present invention, the following conditional expression is satisfied.
Nd1> 1.80 (2)
Here, the value Nd1 is the refractive index of the lens closest to the object side. Conditional expression (2) defines an appropriate range of the refractive index of the lens disposed closest to the object side. When the refractive index Nd1 of the lens closest to the object satisfies the conditional expression (2), astigmatism generated in this lens can be suppressed. As described above, the lens on the most object side has a great influence on the off-axis performance of the entire optical system, and by satisfying this conditional expression (2), the image quality up to a high image height is corrected satisfactorily. Optical performance can be achieved.
Regarding conditional expression (2), the following range Nd1> 1.83 (2) ′
Is more desirable.

  In still another aspect of the present invention, only the lens disposed closest to the object side and the lens disposed immediately after the stop are spherical lenses. Although it is desirable that the lens disposed closest to the object side and immediately after the stop is made of glass, the use of an aspheric glass lens causes a significant cost increase. Therefore, in the present invention, spherical glass lenses are used as these two lenses, and high optical performance is achieved from on-axis to off-axis by setting the power of both groups while realizing cost reduction. In addition, aspherical lenses will be used for the remaining four lenses, excluding these two lenses, which have a large effect on performance fluctuations when temperature changes. An optical system with excellent imaging performance has been realized.

  In still another aspect of the present invention, a cemented lens including a biconcave lens and a biconvex lens is arranged on the most image side in order from the object side. By arranging a cemented lens composed of a biconcave lens and a biconvex lens in this order from the object side, the occurrence of chromatic aberration can be suppressed. In the lens arranged on the most image side, both the on-axis light beam and off-axis light beam passing through are thick, and the influence on on-axis and off-axis performance is great. By making such a lens a cemented lens composed of a biconcave lens and a biconvex lens in order from the object side, axial chromatic aberration and lateral chromatic aberration generated in each lens are canceled out, and the chromatic aberration is suppressed satisfactorily in the entire optical system. be able to.

In still another aspect of the present invention, the following conditional expression is satisfied.
| f2 / f1 | <0.1 (3)
Here, the value f1 is the focal length of the front group, and the value f2 is the focal length of the rear group. Conditional expression (3) defines a preferable range of the ratio of the focal length of the rear group to the focal length of the front group. When the value | f2 / f1 | satisfies the conditional expression (3), the power arrangement of the front group and the rear group is made appropriate, the power of each group does not become too large, and the aberration generated in the entire optical system is good. And high optical performance can be achieved. For conditional expression (3), the following range
| f2 / f1 | <0.08 (3) ′
Is more desirable.

  In order to achieve the above object, a lens unit according to the present invention includes the above-described wide-angle lens and a lens barrel that holds the wide-angle lens.

  In order to achieve the above object, an imaging apparatus according to the present invention includes the above-described wide-angle lens and an imaging element that detects an image obtained by the wide-angle lens.

  According to the imaging apparatus, by providing the above-described wide-angle lens, high weather resistance can be achieved at low cost while realizing good optical performance.

It is a figure explaining a lens unit and imaging device provided with a wide angle lens of one embodiment of the present invention. (A) is sectional drawing, such as a wide angle lens of Example 1, (B)-(D) are aberration diagrams. (A) is sectional drawing, such as a wide angle lens of Example 2, (B)-(D) are aberration diagrams. (A) is sectional drawing, such as a wide angle lens of Example 3, (B)-(D) are aberration diagrams. (A) is sectional drawing, such as a wide angle lens of Example 4, (B)-(D) are aberration diagrams. (A) is sectional drawing, such as a wide angle lens of Example 5, (B)-(D) are aberration diagrams. (A) is sectional drawing, such as a wide angle lens of Example 6, (B)-(D) are aberration diagrams.

  FIG. 1 is a cross-sectional view illustrating an imaging apparatus 100 that is an embodiment of the present invention. The imaging apparatus 100 includes a camera module 30 that forms an image signal, and a processing unit 60 that exhibits the functions of the imaging apparatus 100 by operating the camera module 30.

  The camera module 30 includes a lens unit 40 that includes the wide-angle lens 10 and a sensor unit 50 that converts a subject image formed by the wide-angle lens 10 into an image signal.

  The lens unit 40 includes a wide-angle lens 10 that is an imaging optical system, and a lens barrel 41 that incorporates the wide-angle lens 10. The wide angle lens 10 includes first to sixth lenses L1 to L6. The lens barrel 41 is formed of resin, metal, a mixture of resin and glass fiber, etc., and stores and holds a lens or the like therein. When the lens barrel 41 is formed of, for example, a mixture of glass fiber and resin, the wide-angle lens 10 can be stably fixed with less thermal expansion than the resin. The lens barrel 41 has an opening OP through which light from the object side is incident.

  The total angle of view of the wide-angle lens 10 is 200 ° or more. The first to sixth lenses L1 to L6 constituting the wide-angle lens 10 are held directly or indirectly on the inner surface side of the lens barrel 41 at their flange portions or outer peripheral portions, and the optical axis AX direction and the optical axis Positioning in the direction perpendicular to AX is performed. The lens barrel 41 also supports optical elements other than the lenses L1 to L6, such as an aperture stop (stop) ST and a filter F1.

  The sensor unit 50 includes a solid-state imaging device (imaging device) 51 that photoelectrically converts a subject image formed by the wide-angle lens 10, a substrate 52 that supports the solid-state imaging device 51, and the solid-state imaging device 51 via the substrate 52. And a sensor holder 53 for holding. The solid-state image sensor 51 is, for example, a CMOS image sensor. The substrate 52 includes wiring for operating the solid-state imaging device 51, peripheral circuits, and the like. The sensor holder 53 is formed of a resin or other material, and positions the solid-state image sensor 51 with respect to the optical axis AX. The lens barrel 41 of the lens unit 40 is fixed in a state of being positioned so as to be fitted to the sensor holder 53.

  The solid-state imaging device 51 has a photoelectric conversion unit 51a as the imaging surface I, and a signal processing circuit (not shown) is formed in the vicinity thereof. Pixels, that is, photoelectric conversion elements are two-dimensionally arranged in the photoelectric conversion unit 51a. The solid-state imaging device 51 is not limited to the above-described CMOS type image sensor, and may be a device incorporating another imaging device such as a CCD.

  A filter or the like can be disposed between the lenses constituting the lens unit 40 or between the lens unit 40 and the sensor unit 50. In the example of FIG. 1, the filter F <b> 1 is disposed between the sixth lens L <b> 6 of the wide-angle lens 10 and the solid-state image sensor 51. The filter F1 is a parallel plate assuming an optical low-pass filter, an IR cut filter, a seal glass of the solid-state image sensor 51, and the like. The filter F1 can be arranged as a separate filter member, but it can be given to any lens surface constituting the wide-angle lens 10 without being arranged separately. For example, in the case of an infrared cut filter, an infrared cut coat may be applied on the surface of one or a plurality of lenses.

  The processing unit 60 includes an element driving unit 61, an input unit 62, a storage unit 63, a display unit 64, and a control unit 68. The element driving unit 61 operates the solid-state image sensor 51 by outputting a control signal to a circuit or the like associated with the solid-state image sensor 51. The element driving unit 61 receives a voltage and a clock signal for driving the solid-state imaging device 51 from the control unit 68, and outputs YUV and other digital pixel signals corresponding to the output signal of the solid-state imaging device 51 to an external circuit. You can also do it. The input unit 62 is a part that accepts user operations, the storage unit 63 is a part that stores information necessary for the operation of the imaging apparatus 100, image data acquired by the camera module 30, and the like. This is a part for displaying information to be presented to the user, captured images, and the like. The control unit 68 comprehensively controls operations of the element driving unit 61, the input unit 62, the storage unit 63, and the like, and can perform various image processing on image data obtained by the camera module 30, for example. .

  Although detailed description is omitted, the specific function of the processing unit 60 is appropriately adjusted according to the application of the device in which the imaging apparatus 100 is incorporated. The imaging device 100 can be mounted on devices for various uses such as an in-vehicle camera and a surveillance camera.

  Hereinafter, the wide-angle lens (imaging optical system) 10 according to the first embodiment will be described with reference to FIG. The wide-angle lens 10 illustrated in FIG. 1 has substantially the same configuration as a wide-angle lens 10A of Example 1 described later.

  The illustrated wide-angle lens 10 is a six-lens wide-angle lens including a front group G1, an aperture stop ST, and a positive rear group G2 in order from the object side. Specifically, the wide-angle lens 10 includes, in order from the object side, a first lens L1 having negative power, a second lens L2 having negative power, a third lens L3 having positive power, and an aperture stop. It comprises ST, a fourth lens L4 having positive power, a fifth lens L5 having negative power, and a sixth lens L6 having positive power. The cemented lens CL is disposed on the most image side. The cemented lens CL includes a fifth lens L5 that is a biconcave lens and a sixth lens L6 that is a biconvex lens in order from the object side, and these are cemented.

  This wide-angle lens 10 employs a lens arrangement composed of a front group G1, an aperture stop ST, and a positive rear group G2 in order from the object side, and widens the angle while reducing the front lens diameter. Can be achieved.

  In the wide-angle lens 10, the first lens L1 that is disposed closest to the object side and the fourth lens L4 that is disposed immediately after the aperture stop ST are glass lenses. For in-vehicle cameras and surveillance cameras, there is a demand for a lens that can be used in a wide temperature range with little performance degradation even under severe conditions. In the first lens L1 arranged on the most object side, the off-axis light beam passes through a high position of the lens, and the influence on off-axis performance is great. Further, both the on-axis light beam and the off-axis light beam that pass through the fourth lens L4 disposed immediately after the aperture stop ST are thick and have a great influence on the on-axis and off-axis performance. By making these lenses L1 and L4 into glass, since the refractive index change due to temperature change is smaller than plastic, glass suppresses spherical aberration and curvature of field fluctuation due to temperature change, and it is on-axis even in harsh environments. High optical performance can be achieved from to the periphery. Further, by using a material that is not easily damaged, such as glass, for the first lens L1 that is in direct contact with the outside air, it is possible to prevent deterioration of optical performance due to the damage.

  In the wide-angle lens 10, only the first lens L1 disposed closest to the object side and the fourth lens L4 disposed immediately after the aperture stop ST are spherical lenses. The first lens L1 arranged closest to the object side and the fourth lens L4 arranged immediately after the aperture stop ST are preferably made of glass. However, if an aspheric glass lens is used, the cost increases significantly. End up. Therefore, spherical glass lenses are used as the two first and fourth lenses L1 and L4, and the optical performance is high from on-axis to off-axis by setting the power of both groups G1 and G2, while realizing cost reduction. Has achieved. All of the remaining second, third, fifth, and sixth lenses L2, L3, L5, and L6 except for the first and fourth lenses L1 and L4, which have a large effect on performance fluctuations when the temperature changes, are all included. An aspheric lens will be adopted. Thereby, the generation of coma aberration can be suppressed, and an optical system excellent in depiction performance from on-axis to the periphery can be realized. If a plastic lens is used as the material for the aspheric lens, the cost can be reduced.

  In the wide-angle lens 10, a cemented lens CL including a fifth lens L 5 that is a biconcave lens and a sixth lens L 6 that is a biconvex lens are arranged on the most image side in order from the object side. By arranging such a cemented lens CL closest to the image side, the occurrence of chromatic aberration can be suppressed. In the lens arranged on the most image side, both the on-axis light beam and off-axis light beam passing through are thick, and the influence on on-axis and off-axis performance is great. By making such a lens a cemented lens CL composed of a biconcave fifth lens L5 and a biconvex sixth lens L6 in this order from the object side, axial chromatic aberration generated in each of the lenses L5 and L6. Further, the chromatic aberration of magnification can be canceled and the chromatic aberration can be suppressed satisfactorily in the entire optical system.

The wide-angle lens 10 satisfies the following conditional expression (1).
| f / f1 | <0.028 (1)
Here, the value f1 is the focal length of the front group G1, and the value f is the focal length of the entire system.

Conditional expression (1) defines the ratio of the focal length of the entire system to the focal length of the front group G1, and is characterized by the small power of the front group G1. When the value | f / f1 | satisfies the conditional expression (1), the G1 power of the front group does not increase too much, and field curvature, coma aberration, and chromatic aberration of magnification are suppressed, and high optical performance is achieved from on-axis to the periphery. Can be achieved. Further, since the power of the front group G1 does not become excessively large, it is possible to suppress aberration fluctuations due to decentering errors during lens assembly. For conditional expression (1), the following range
| f / f1 | <0.025 (1) '
Is more desirable.

The wide-angle lens 10 satisfies the following conditional expression (2).
Nd1> 1.80 (2)
Here, the value Nd1 is the refractive index of the first lens L1 closest to the object side. Conditional expression (2) defines an appropriate range of the refractive index of the first lens L1 arranged closest to the object side. When the refractive index Nd1 of the lens closest to the object satisfies the conditional expression (2), astigmatism generated in the first lens L1 can be suppressed. As described above, the effect of the first lens L1 closest to the object side on the off-axis performance of the entire optical system is large. By satisfying this conditional expression (2), the image quality up to a high image height can be corrected well. And high optical performance can be achieved. Regarding conditional expression (2), the following range Nd1> 1.83 (2) ′
Is more desirable.

The wide-angle lens 10 satisfies the following conditional expression (3).
| f2 / f1 | <0.1 (3)
Here, the value f1 is the focal length of the front group G1, and the value f2 is the focal length of the rear group G2. Conditional expression (3) defines the ratio of the focal length of the rear group G2 to the focal length of the front group G1. When the value | f2 / f1 | satisfies the conditional expression (3), the power arrangement of the front group G1 and the rear group G2 is made appropriate, and the power of each of the groups G1 and G2 does not become too large. It is possible to satisfactorily suppress the generated aberration and achieve high optical performance. For conditional expression (3), the following range
| f2 / f1 | <0.08 (3) ′
Is more desirable.

ただし、
Ａｉ：ｉ次の非球面係数
Ｒ ：曲率半径
Ｋ ：円錐定数 The wide-angle lens 10 may further include a lens or other optical element that has substantially no power (for example, a lens, a filter member, etc.).
〔Example〕
Examples of the wide angle lens of the present invention will be described below. Symbols used in each example are as follows.
f: Focal length 2ω of the entire system: Maximum total angle of view TL: Optical total length Fno: F number R: Radius of curvature D: Axis upper surface distance Nd: Refractive index of lens material with respect to d-line vd: Abbe number of lens material In FIG. 5, the surface described with “*” after each surface number is a surface having an aspherical shape, and the aspherical shape has the vertex of the surface as the origin, the X axis in the optical axis direction, and the optical axis. And the height in the vertical direction is represented by the following “Equation 1”.

However,
Ai: i-order aspheric coefficient R: radius of curvature K: conic constant

Example 1
The overall specifications of the wide-angle lens of Example 1 are shown below.
f = 0.97mm
2ω = 220 °
TL = 12.60mm
Fno = 2.00

The lens surface data of the wide-angle lens of Example 1 is shown in Table 1 below. In Table 1 below, the surface number is represented by “Surf. N”, the aperture stop is represented by “ST”, and the infinity is represented by “INF”.
[Table 1]
Surf. NR (mm) D (mm) Nd vd
1 12.810 1.028 1.8348 42.72
2 3.824 1.523
* 3 10.412 0.628 1.5459 56.16
* 4 1.591 1.922
* 5 -2.539 1.361 1.6346 23.87
* 6 -1.911 0.305
7ST INF 0.130
8 7.579 1.267 1.7292 54.67
9 -2.570 0.369
* 10 -4.805 0.500 1.5459 56.16
* 11 1.423 0.015 1.5140 42.83
* 12 1.423 1.952 1.6346 23.87
* 13 -1.910 0.854
14 INF 0.200 1.5168 64.19
15 INF 0.447
16 INF 0.000

The aspheric coefficients of the lens surfaces of Example 1 are shown in Table 2 below. In the following (including the lens data in the table), a power of 10 (for example, 2.5 × 10 ⁻⁰² ) is expressed using E (for example, 2.5E-02).
[Table 2]
Third side
K = 8.2528E + 00, A4 = 4.6306E-03, A6 = -6.1485E-05,
A8 = -2.0866E-05, A10 = -2.2643E-06, A12 = 3.9267E-07,
A14 = 4.6273E-08, A16 = -1.1416E-08, A18 = 4.7261E-10
4th page
K = -1.5119E + 00, A4 = 3.4228E-02, A6 = 4.2339E-02,
A8 = -7.4535E-02, A10 = 8.6116E-02, A12 = -5.3555E-02,
A14 = 1.7453E-02, A16 = -2.2848E-03, A18 = 0.0000E + 00
5th page
K = 1.5715E + 00, A4 = -3.9754E-02, A6 = 4.9645E-02,
A8 = 2.1925E-04, A10 = -2.1779E-01, A12 = 4.6789E-01,
A14 = -4.4376E-01, A16 = 2.0427E-01, A18 = -3.6955E-02
6th page
K = 5.0401E-01, A4 = 3.6480E-02, A6 = -3.0284E-02,
A8 = 9.5293E-02, A10 = -1.2801E-01, A12 = 1.0077E-01,
A14 = -4.2412E-02, A16 = 7.6856E-03, A18 = 0.0000E + 00
10th page
K = -3.7420E + 01, A4 = 1.6710E-02, A6 = -1.2965E-01,
A8 = 1.9349E-01, A10 = -1.8823E-01, A12 = 1.3255E-01,
A14 = -7.1428E-02, A16 = 2.0472E-02, A18 = 0.0000E + 00
11th page
K = -8.6718E-01, A4 = 4.7997E-01, A6 = -6.2814E-01,
A8 = 4.1866E-01, A10 = -1.3465E-01, A12 = 8.2899E-03,
A14 = 2.4207E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00
12th page
K = -8.6718E-01, A4 = 4.7997E-01, A6 = -6.2814E-01,
A8 = 4.1866E-01, A10 = -1.3465E-01, A12 = 8.2899E-03,
A14 = 2.4207E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00
Side 13
K = -2.9097E + 00, A4 = 1.9240E-02, A6 = -1.3714E-01,
A8 = 2.6051E-01, A10 = -2.6638E-01, A12 = 1.5359E-01,
A14 = -4.6685E-02, A16 = 5.8385E-03, A18 = 0.0000E + 00

The lens group focal length of Example 1 is shown in Table 3 below.
[Table 3]
Front group -35.396mm
Rear group 2.956mm

  FIG. 2A is a cross-sectional view of the wide-angle lens 10A and the like of the first embodiment. The wide-angle lens 10A has negative power and a first meniscus lens L1 convex toward the object side, a second meniscus lens L2 negative and concave toward the image side, and positive power. A convex meniscus third lens L3, a biconvex fourth lens L4, a biconcave fifth lens L5, and a biconvex sixth lens L6 are provided. The first to third lenses L1 to L3 constitute a front group G1, the fourth to sixth lenses L4 to L6 constitute a rear group G2, and an aperture stop is provided between the front group G1 and the rear group G2. ST is arranged. The most image-side cemented lens CL is obtained by cementing a fifth lens L5 that is a biconcave lens and a sixth lens L6 that is a biconvex lens. A filter F1 having an appropriate thickness is disposed between the sixth lens L6 and the solid-state imaging element 51. The filter F1 is a parallel plate assuming an optical low-pass filter, an IR cut filter, a seal glass of the solid-state image sensor 51, and the like. Reference numeral I denotes an imaging surface that is a projection surface of the solid-state imaging device 51. Note that the symbols F1 and I are the same in the following embodiments.

  2B to 2D show aberration diagrams (spherical aberration, astigmatism, and distortion aberration) of the wide-angle lens 10A of Example 1. FIG.

(Example 2)
The overall specifications of the wide-angle lens of Example 2 are shown below.
f = 0.97mm
2ω = 220 °
TL = 12.50mm
Fno = 2.00

The data of the lens surface of the wide-angle lens of Example 2 is shown in Table 4 below.
[Table 4]
Surf. NR (mm) D (mm) Nd vd
1 12.833 1.030 1.8348 42.72
2 3.948 1.457
* 3 10.354 0.600 1.5459 56.16
* 4 1.575 1.930
* 5 -2.513 1.389 1.6346 23.87
* 6 -1.910 0.308
7ST INF 0.130
8 7.519 1.265 1.7292 54.67
9 -2.584 0.335
* 10 -5.008 0.500 1.5459 56.16
* 11 1.369 0.015 1.5140 42.83
* 12 1.369 1.941 1.6346 23.87
* 13 -1.915 0.903
14 INF 0.150 1.5168 64.19
15 INF 0.447
16 INF 0.000

The aspherical coefficient of the lens surface of Example 2 is shown in Table 5 below.
[Table 5]
Third side
K = 8.2921E + 00, A4 = 4.6147E-03, A6 = -6.7867E-05,
A8 = -2.0875E-05, A10 = -2.1899E-06, A12 = 4.0603E-07,
A14 = 4.7696E-08, A16 = -1.1343E-08, A18 = 4.6375E-10
4th page
K = -1.4955E + 00, A4 = 3.4590E-02, A6 = 4.7498E-02,
A8 = -8.8441E-02, A10 = 1.0154E-01, A12 = -6.2175E-02,
A14 = 1.9774E-02, A16 = -2.5234E-03, A18 = 0.0000E + 00
5th page
K = 1.5445E + 00, A4 = -3.2038E-02, A6 = -1.7251E-04,
A8 = 1.6777E-01, A10 = -5.5512E-01, A12 = 8.8156E-01,
A14 = -7.4537E-01, A16 = 3.2446E-01, A18 = -5.7103E-02
6th page
K = 5.1312E-01, A4 = 3.6155E-02, A6 = -2.9844E-02,
A8 = 9.5431E-02, A10 = -1.2776E-01, A12 = 1.0045E-01,
A14 = -4.2600E-02, A16 = 7.8721E-03, A18 = 0.0000E + 00
10th page
K = -3.8031E + 01, A4 = 1.4371E-02, A6 = -1.2224E-01,
A8 = 1.9407E-01, A10 = -2.1780E-01, A12 = 1.8087E-01,
A14 = -1.0167E-01, A16 = 2.6901E-02, A18 = 0.0000E + 00
11th page
K = -9.7016E-01, A4 = 4.6320E-01, A6 = -6.3623E-01,
A8 = 4.6743E-01, A10 = -1.8987E-01, A12 = 3.6578E-02,
A14 = -3.1201E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00
12th page
K = -9.7016E-01, A4 = 4.6320E-01, A6 = -6.3623E-01,
A8 = 4.6743E-01, A10 = -1.8987E-01, A12 = 3.6578E-02,
A14 = -3.1201E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00
Side 13
K = -2.9090E + 00, A4 = 1.7730E-02, A6 = -1.3243E-01,
A8 = 2.5244E-01, A10 = -2.5847E-01, A12 = 1.4955E-01,
A14 = -4.5680E-02, A16 = 5.7418E-03, A18 = 0.0000E + 00

The lens group focal length of Example 2 is shown in Table 6 below.
[Table 6]
Front group -40.435mm
Rear group 2.930mm

  FIG. 3A is a cross-sectional view of the wide-angle lens 10B and the like of the second embodiment. The wide-angle lens 10B has a positive meniscus type first lens L1 having negative power and convex on the object side, a meniscus type second lens L2 having negative power and concave on the image side, and positive power. A convex meniscus third lens L3, a biconvex fourth lens L4, a biconcave fifth lens L5, and a biconvex sixth lens L6 are provided. The first to third lenses L1 to L3 constitute a front group G1, the fourth to sixth lenses L4 to L6 constitute a rear group G2, and an aperture stop is provided between the front group G1 and the rear group G2. ST is arranged. The most image-side cemented lens CL is obtained by cementing a fifth lens L5 that is a biconcave lens and a sixth lens L6 that is a biconvex lens. A filter F1 having an appropriate thickness is disposed between the sixth lens L6 and the solid-state imaging element 51.

  3B to 3D show aberration diagrams (spherical aberration, astigmatism, and distortion aberration) of the wide-angle lens 10B of Example 2. FIG.

Example 3
The overall specifications of the wide-angle lens of Example 3 are shown below.
f = 0.97mm
2ω = 220 °
TL = 12.50mm
Fno = 1.90

Data of the lens surface of the wide-angle lens of Example 3 is shown in Table 7 below.
[Table 7]
Surf. NR (mm) D (mm) Nd vd
1 12.869 1.000 1.8348 42.72
2 4.017 1.446
* 3 10.283 0.600 1.5459 56.16
* 4 1.590 1.957
* 5 -2.476 1.399 1.6346 23.87
* 6 -1.903 0.330
7ST INF 0.130
8 7.448 1.267 1.7292 54.67
9 -2.623 0.321
* 10 -5.361 0.500 1.5459 56.16
* 11 1.300 0.015 1.5140 42.83
* 12 1.300 1.935 1.6346 23.87
* 13 -1.926 0.903
14 INF 0.150 1.5168 64.19
15 INF 0.448
16 INF 0.000

The aspherical coefficients of the lens surfaces of Example 3 are shown in Table 8 below.
[Table 8]
Third side
K = 8.3539E + 00, A4 = 4.4946E-03, A6 = -7.8563E-05,
A8 = -2.1150E-05, A10 = -2.1291E-06, A12 = 4.1787E-07,
A14 = 4.8739E-08, A16 = -1.1313E-08, A18 = 4.5321E-10
4th page
K = -1.5278E + 00, A4 = 3.4118E-02, A6 = 5.0038E-02,
A8 = -9.2027E-02, A10 = 1.0117E-01, A12 = -5.9380E-02,
A14 = 1.8083E-02, A16 = -2.2128E-03, A18 = 0.0000E + 00
5th page
K = 1.4577E + 00, A4 = -2.9957E-02, A6 = 2.5317E-03,
A8 = 1.2951E-01, A10 = -4.3034E-01, A12 = 6.7620E-01,
A14 = -5.6057E-01, A16 = 2.3830E-01, A18 = -4.0880E-02
6th page
K = 5.0516E-01, A4 = 3.6508E-02, A6 = -3.0558E-02,
A8 = 9.4879E-02, A10 = -1.2652E-01, A12 = 1.0040E-01,
A14 = -4.3041E-02, A16 = 7.9334E-03, A18 = 0.0000E + 00
10th page
K = -3.9882E + 01, A4 = 7.8710E-03, A6 = -8.9038E-02,
A8 = 1.2240E-01, A10 = -1.2793E-01, A12 = 1.1600E-01,
A14 = -7.4742E-02, A16 = 2.1397E-02, A18 = 0.0000E + 00
11th page
K = -1.0965E + 00, A4 = 4.0739E-01, A6 = -5.2798E-01,
A8 = 3.4595E-01, A10 = -1.0842E-01, A12 = 8.1141E-03,
A14 = 8.6200E-04, A16 = 0.0000E + 00, A18 = 0.0000E + 00
12th page
K = -1.0965E + 00, A4 = 4.0739E-01, A6 = -5.2798E-01,
A8 = 3.4595E-01, A10 = -1.0842E-01, A12 = 8.1141E-03,
A14 = 8.6200E-04, A16 = 0.0000E + 00, A18 = 0.0000E + 00
Side 13
K = -2.9963E + 00, A4 = 1.6181E-02, A6 = -1.2743E-01,
A8 = 2.4561E-01, A10 = -2.5287E-01, A12 = 1.4704E-01,
A14 = -4.5105E-02, A16 = 5.6873E-03, A18 = 0.0000E + 00

The lens group focal lengths of Example 3 are shown in Table 9 below.
[Table 9]
Front group -50.384mm
Rear group 2.924mm

  FIG. 4A is a cross-sectional view of the wide-angle lens 10C of Example 3 and the like. The wide-angle lens 10C has a negative meniscus type first lens L1 having negative power and convex on the object side, a meniscus type second lens L2 having negative power and concave on the image side, and has positive power. A convex meniscus third lens L3, a biconvex fourth lens L4, a biconcave fifth lens L5, and a biconvex sixth lens L6 are provided. The first to third lenses L1 to L3 constitute a front group G1, the fourth to sixth lenses L4 to L6 constitute a rear group G2, and an aperture stop is provided between the front group G1 and the rear group G2. ST is arranged. The most image-side cemented lens CL is obtained by cementing a fifth lens L5 that is a biconcave lens and a sixth lens L6 that is a biconvex lens. A filter F1 having an appropriate thickness is disposed between the sixth lens L6 and the solid-state imaging element 51.

  4B to 4D show aberration diagrams (spherical aberration, astigmatism, and distortion aberration) of the wide-angle lens 10C of Example 3. FIG.

Example 4
The overall specifications of the wide-angle lens of Example 4 are shown below.
f = 0.97mm
2ω = 220 °
TL = 12.50mm
Fno = 2.10

Data of the lens surface of the wide-angle lens of Example 4 is shown in Table 10 below.
[Table 10]
Surf. NR (mm) D (mm) Nd vd
1 13.020 1.000 1.8348 42.72
2 4.065 1.425
* 3 10.212 0.600 1.5459 56.16
* 4 1.580 1.961
* 5 -2.495 1.403 1.6346 23.87
* 6 -1.906 0.416
7ST INF 0.130
8 7.879 1.169 1.7292 54.67
9 -2.631 0.343
* 10 -5.608 0.500 1.5459 56.16
* 11 1.300 0.015 1.5140 42.83
* 12 1.300 1.938 1.6346 23.87
* 13 -1.942 0.902
14 INF 0.150 1.5168 64.19
15 INF 0.448
16 INF 0.000

The aspherical coefficients of the lens surfaces of Example 4 are shown in Table 11 below.
[Table 11]
Third side
K = 8.3205E + 00, A4 = 4.2840E-03, A6 = -9.5699E-05,
A8 = -2.1284E-05, A10 = -2.0307E-06, A12 = 4.3208E-07,
A14 = 4.9965E-08, A16 = -1.1285E-08, A18 = 4.3941E-10
4th page
K = -1.4864E + 00, A4 = 3.7721E-02, A6 = 4.3935E-02,
A8 = -8.5626E-02, A10 = 9.6392E-02, A12 = -5.7009E-02,
A14 = 1.7336E-02, A16 = -2.1090E-03, A18 = 0.0000E + 00
5th page
K = 1.4496E + 00, A4 = -1.8418E-02, A6 = -6.2587E-02,
A8 = 3.2141E-01, A10 = -7.6547E-01, A12 = 1.0293E + 00,
A14 = -7.8274E-01, A16 = 3.1555E-01, A18 = -5.2372E-02
6th page
K = 4.8889E-01, A4 = 3.5423E-02, A6 = -2.6339E-02,
A8 = 8.7240E-02, A10 = -1.2344E-01, A12 = 1.0205E-01,
A14 = -4.3986E-02, A16 = 7.8154E-03, A18 = 0.0000E + 00
10th page
K = -3.9510E + 01, A4 = 6.9494E-03, A6 = -1.0067E-01,
A8 = 2.1598E-01, A10 = -3.5052E-01, A12 = 3.6659E-01,
A14 = -2.1077E-01, A16 = 4.9524E-02, A18 = 0.0000E + 00
11th page
K = -1.0719E + 00, A4 = 3.9219E-01, A6 = -5.3108E-01,
A8 = 4.1755E-01, A10 = -2.0407E-01, A12 = 6.0276E-02,
A14 = -9.7374E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00
12th page
K = -1.0719E + 00, A4 = 3.9219E-01, A6 = -5.3108E-01,
A8 = 4.1755E-01, A10 = -2.0407E-01, A12 = 6.0276E-02,
A14 = -9.7374E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00
Side 13
K = -2.8788E + 00, A4 = 1.2662E-02, A6 = -1.1288E-01,
A8 = 2.2246E-01, A10 = -2.3304E-01, A12 = 1.3759E-01,
A14 = -4.2808E-02, A16 = 5.4670E-03, A18 = 0.0000E + 00

The lens group focal length of Example 4 is shown in Table 12 below.
[Table 12]
Front group -55.961mm
Rear group 2.928mm

  FIG. 5A is a cross-sectional view of the wide-angle lens 10D according to the fourth embodiment. The wide-angle lens 10D has a negative meniscus type first lens L1 having negative power and convex on the object side, a meniscus type second lens L2 having negative power and concave on the image side, and has positive power. A convex meniscus third lens L3, a biconvex fourth lens L4, a biconcave fifth lens L5, and a biconvex sixth lens L6 are provided. The first to third lenses L1 to L3 constitute a front group G1, the fourth to sixth lenses L4 to L6 constitute a rear group G2, and an aperture stop is provided between the front group G1 and the rear group G2. ST is arranged. The most image-side cemented lens CL is obtained by cementing a fifth lens L5 that is a biconcave lens and a sixth lens L6 that is a biconvex lens. A filter F1 having an appropriate thickness is disposed between the sixth lens L6 and the solid-state imaging element 51.

  FIGS. 5B to 5D show aberration diagrams (spherical aberration, astigmatism, and distortion aberration) of the wide-angle lens 10D of Example 4. FIGS.

(Example 5)
The overall specifications of the wide-angle lens of Example 5 are shown below.
f = 0.98mm
2ω = 220 °
TL = 12.36mm
Fno = 2.00

Data on the lens surface of the wide-angle lens of Example 5 is shown in Table 13 below.
[Table 13]
Surf. NR (mm) D (mm) Nd vd
1 12.100 1.000 1.8042 46.50
2 3.690 1.741
* 3 -25.022 0.700 1.5459 56.16
* 4 1.976 1.671
* 5 -2.901 1.474 1.6346 23.87
* 6 -1.918 0.087
7ST INF 0.140
8 7.076 1.300 1.7292 54.67
9 -2.273 0.344
* 10 -2.920 0.500 1.5459 56.16
* 11 2.000 0.015 1.5140 42.83
* 12 2.000 1.884 1.6346 23.87
* 13 -1.922 1.103
14 INF 0.300 1.5168 64.19
15 INF 0.100
16 INF 0.000

The aspheric coefficients of the lens surfaces of Example 5 are shown in Table 14 below.
[Table 14]
Third side
K = 5.0000E + 01, A4 = -1.1843E-02, A6 = 3.5567E-02,
A8 = -2.0180E-02, A10 = 6.4471E-03, A12 = -1.2974E-03,
A14 = 1.6738E-04, A16 = -1.3416E-05, A18 = 6.0571E-07,
A20 = -1.1703E-08
4th page
K = 1.7167E-01, A4 = -6.8914E-03, A6 = -4.6392E-02,
A8 = 2.3922E-01, A10 = -2.4193E-01, A12 = 8.6396E-02,
A14 = 1.1641E-02, A16 = -1.6340E-02, A18 = 4.0391E-03,
A20 = -3.2599E-04
5th page
K = 3.8487E-01, A4 = -4.1708E-02, A6 = 2.0932E-02,
A8 = -2.5775E-02, A10 = 2.1375E-02, A12 = -6.6582E-03,
A14 = 7.1743E-04, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00
6th page
K = 9.4846E-01, A4 = 5.3942E-02, A6 = -4.4237E-02,
A8 = 1.4659E-01, A10 = -1.7996E-01, A12 = 1.1065E-01,
A14 = -2.4442E-02, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00
10th page
K = -1.4455E + 01, A4 = -3.7506E-03, A6 = -7.2062E-02,
A8 = 6.1547E-02, A10 = -2.5592E-02, A12 = 4.6563E-03,
A14 = 0.0000E + 00, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00
11th page
K = -1.8100E + 00, A4 = 6.1146E-01, A6 = -7.1245E-01,
A8 = 4.2615E-01, A10 = -1.3137E-01, A12 = 1.4413E-02,
A14 = 1.8170E-04, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00
12th page
K = -1.8100E + 00, A4 = 6.1146E-01, A6 = -7.1245E-01,
A8 = 4.2615E-01, A10 = -1.3137E-01, A12 = 1.4413E-02,
A14 = 1.8170E-04, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00
Side 13
K = -1.7713E + 01, A4 = -2.1079E-01, A6 = 2.5018E-01,
A8 = -2.0201E-01, A10 = 1.0154E-01, A12 = -2.7420E-02,
A14 = 3.0890E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00

The lens group focal lengths of Example 5 are shown in Table 15 below.
[Table 15]
Front group 48.859mm
Rear group 3.024mm

  FIG. 6A is a cross-sectional view of the wide-angle lens 10E according to the fifth embodiment. The wide-angle lens 10E has a negative meniscus type first lens L1 having negative power and convex on the object side, a meniscus type second lens L2 having negative power and concave on the image side, and has positive power. A convex meniscus third lens L3, a biconvex fourth lens L4, a biconcave fifth lens L5, and a biconvex sixth lens L6 are provided. The first to third lenses L1 to L3 constitute a front group G1, the fourth to sixth lenses L4 to L6 constitute a rear group G2, and an aperture stop is provided between the front group G1 and the rear group G2. ST is arranged. The most image-side cemented lens CL is obtained by cementing a fifth lens L5 that is a biconcave lens and a sixth lens L6 that is a biconvex lens. A filter F1 having an appropriate thickness is disposed between the sixth lens L6 and the solid-state imaging element 51.

  6B to 6D show aberration diagrams (spherical aberration, astigmatism, and distortion aberration) of the wide-angle lens 10E of Example 5. FIG.

(Example 6)
The overall specifications of the wide-angle lens of Example 6 are shown below.
f = 0.98mm
2ω = 220 °
TL = 12.31mm
Fno = 2.00

Data on the lens surface of the wide-angle lens of Example 6 is shown in Table 16 below.
[Table 16]
Surf. NR (mm) D (mm) Nd vd
1 12.100 1.000 1.8042 46.50
2 3.690 1.746
* 3 -24.411 0.700 1.5459 56.16
* 4 1.975 1.668
* 5 -2.787 1.427 1.6346 23.87
* 6 -1.861 0.093
7ST INF 0.140
8 7.555 1.314 1.7292 54.67
9 -2.235 0.336
* 10 -2.960 0.500 1.5459 56.16
* 11 2.000 0.015 1.5140 42.83
* 12 2.000 1.872 1.6346 23.87
* 13 -1.957 1.101
14 INF 0.300 1.5168 64.19
15 INF 0.100
16 INF 0.000

Table 17 below shows the aspheric coefficients of the lens surfaces of Example 6.
[Table 17]
Third side
K = 5.0000E + 01, A4 = -1.1205E-02, A6 = 3.5082E-02,
A8 = -2.0070E-02, A10 = 6.4498E-03, A12 = -1.3033E-03,
A14 = 1.6858E-04, A16 = -1.3529E-05, A18 = 6.1097E-07,
A20 = -1.1799E-08
4th page
K = 1.6680E-01, A4 = -1.3385E-03, A6 = -7.8650E-02,
A8 = 3.2581E-01, A10 = -3.7397E-01, A12 = 2.0211E-01,
A14 = -4.7872E-02, A16 = 1.1348E-03, A18 = 1.3473E-03,
A20 = -1.5777E-04
5th page
K = 6.7043E-01, A4 = -4.3363E-02, A6 = 2.2998E-02,
A8 = -2.9954E-02, A10 = 2.8619E-02, A12 = -1.0566E-02,
A14 = 1.3553E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00
6th page
K = -1.9154E + 00, A4 = -3.4077E-03, A6 = -2.0397E-02,
A8 = 5.2293E-02, A10 = -4.5854E-02, A12 = 1.4082E-02,
A14 = 1.1180E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00
10th page
K = -1.4436E + 01, A4 = 2.7718E-03, A6 = -8.4443E-02,
A8 = 7.4824E-02, A10 = -3.2637E-02, A12 = 5.9093E-03,
A14 = 0.0000E + 00, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00
11th page
K = -1.7548E + 00, A4 = 6.2505E-01, A6 = -7.3548E-01,
A8 = 4.3838E-01, A10 = -1.2974E-01, A12 = 1.0894E-02,
A14 = 1.0075E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00
12th page
K = -1.7548E + 00, A4 = 6.2505E-01, A6 = -7.3548E-01,
A8 = 4.3838E-01, A10 = -1.2974E-01, A12 = 1.0894E-02,
A14 = 1.0075E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00
Side 13
K = -1.8836E + 01, A4 = -2.1234E-01, A6 = 2.5613E-01,
A8 = -2.0938E-01, A10 = 1.0641E-01, A12 = -2.9009E-02,
A14 = 3.2885E-03, A16 = 0.0000E + 00, A18 = 0.0000E + 00,
A20 = 0.0000E + 00

The lens group focal length of Example 6 is shown in Table 18 below.
[Table 18]
Front group 36.218mm
Rear group 3.023mm

  FIG. 7A is a cross-sectional view of the wide-angle lens 10F and the like of the sixth embodiment. The wide-angle lens 10F has a negative power, a first meniscus lens L1 that is convex on the object side, a second meniscus lens L2 that has a negative power and is concave on the image side, and a positive power. A convex meniscus third lens L3, a biconvex fourth lens L4, a biconcave fifth lens L5, and a biconvex sixth lens L6 are provided. The first to third lenses L1 to L3 constitute a front group G1, the fourth to sixth lenses L4 to L6 constitute a rear group G2, and an aperture stop is provided between the front group G1 and the rear group G2. ST is arranged. The most image-side cemented lens CL is obtained by cementing a fifth lens L5 that is a biconcave lens and a sixth lens L6 that is a biconvex lens. A filter F1 having an appropriate thickness is disposed between the sixth lens L6 and the solid-state imaging element 51.

  7B to 7D show aberration diagrams (spherical aberration, astigmatism, and distortion aberration) of the wide-angle lens 10F of Example 6. FIG.

Table 19 below summarizes the values of Examples 1 to 6 corresponding to the conditional expressions (1) to (3) for reference.
[Table 19]

  As described above, the wide-angle lens and the like have been described according to the embodiment. However, the wide-angle lens according to the present invention is not limited to the above-described embodiment or examples, and various modifications can be made. For example, the front group G1 can be composed of four sheets and the positive rear group G2 can be composed of two sheets, or the front group G1 can be composed of two sheets and the positive rear group G2 can be composed of four sheets.

  Moreover, in the said Example, the filter F1 divides | segments the filter F1 into two sheets, and each has another role at the time of imaging with visible light or near-infrared light in uses, such as a vehicle-mounted camera and a surveillance camera. It is also possible to take the configuration as described above.

AX: optical axis, CL: cemented lens, F1: filter, G1: front group, G2: rear group, I: imaging surface, L1 to L6 ... lens, OP ... aperture, 10, 10A to 10D ... wide angle lens, 30 ... Camera module 40 ... Lens unit 41 ... Lens barrel 50 ... Sensor unit 51 ... Solid-state imaging device 53 ... Sensor holder 60 ... Processing unit 61 ... Element drive unit 62 ... Input unit 63 ... Storage unit 64 ... display unit, 68 ... control unit, 100 ... imaging device

Claims (8)

In order from the object side, a wide-angle lens having a six-lens configuration including a front group, a diaphragm, and a positive rear group,
A wide angle lens satisfying the following conditional expression.
| f / f1 | <0.028 (1)
f1: focal length of the front group f: focal length of the entire system   The wide-angle lens according to claim 1, wherein the lens disposed closest to the object side and the lens disposed immediately after the aperture stop are glass lenses. The wide-angle lens according to claim 1, wherein the following conditional expression is satisfied.
Nd1> 1.80 (2)
Nd1: Refractive index of the lens closest to the object   The wide-angle lens according to claim 2, wherein only the lens disposed closest to the object side and the lens disposed immediately after the stop are spherical lenses.   The wide-angle lens according to any one of claims 1 to 4, wherein a cemented lens including a biconcave lens and a biconvex lens is arranged on the most image side in order from the object side. The wide-angle lens according to claim 1, wherein the following conditional expression is satisfied.
| f2 / f1 | <0.1 (3)
f1: Focal length of the front group f2: Focal length of the rear group   A lens unit comprising: the wide-angle lens according to claim 1; and a lens barrel that holds the wide-angle lens.   An imaging apparatus comprising: the wide-angle lens according to claim 1; and an imaging device that detects an image obtained by the wide-angle lens.

Images