Imaging lens

Abstract

An image pickup lens includes a cemented lens having positive refractive power and including a spherical lens and a liquid-drop lens. The image pickup lens has four or five lenses including the cemented lens having refractive power.

Description

TECHNICAL FIELD

[0001] The present application relates to an optical element, and more particularly to an image pickup lens. BACKGROUND

[0002] The optical properties of an optical lens, such as surface shape, refractive index, and radius of curvature, are often dependent on the manufacturing process and are often limited. For aspherical lenses, a complex molding process can be required, which is costly. Therefore, there is a need for a technique that can manufacture various optical lenses with a simpler process and at a lower cost. SUMMARY

[0003] The present application provides an image pickup lens having a margin for elastically adjusting the overall refractive index, surface shape, and radius of curvature of the optical properties.

[0004] According to an embodiment of the present application, an image pickup lens includes a cemented lens having positive refractive power, and the cemented lens includes a spherical lens and a liquid drop lens. The image pickup lens has four or five lenses including the cemented lens having refractive power.

[0005] Based on the above, the image pickup lens provided by the embodiments of the present application combines the liquid drop lens and the solid lens to form a cemented lens, mainly utilizes the high plasticity of the liquid drop lens to elastically adjust the overall refractive index, surface shape, and radius of curvature of the optical properties of the cemented lens, and breaks through the manufacturing limitations of the traditional solid lens.

[0006] In order to make the above features and advantages of the present application more obvious and easy to understand, the following specific embodiments are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0007] FIG. 1A A schematic diagram of an image pickup lens according to a first embodiment of the present application is shown. FIG. 1B A schematic diagram of the field curvature of the image pickup lens of the first embodiment is shown, FIG. 1C A schematic diagram of the distortion of the image pickup lens of the first embodiment is shown. FIG. 1D

[0008] A schematic diagram of an image pickup lens according to a second embodiment of the present application is shown. FIG. 2A A schematic diagram of the field curvature of the image pickup lens of the second embodiment is shown, FIG. 2B A schematic diagram of the distortion of the image pickup lens of the second embodiment is shown. FIG. 2C FIG. 2D A schematic diagram of an image pickup lens according to a third embodiment of the present application is shown.

[0009] A schematic diagram of the field curvature of the image pickup lens of the third embodiment is shown, FIG. 3A A schematic diagram of the distortion of the image pickup lens of the third embodiment is shown. FIG. 3B FIG. 3C FIG. 3D ​​This is a schematic diagram of the distortion of the imaging lens in the third embodiment.

[0010] Explanation of icon numbers:

[0011] 0: Aperture;

[0012] 1, 2, 3, 4, 5, 6, 7: Lenses;

[0013] 8: Filters;

[0014] 10: Image capture lens;

[0015] 15, 25, 35, 45, 55, 65, 75, 85: Side view of the object;

[0016] 16, 26, 36, 46, 56, 66, 76, 86: like a side view;

[0017] 99: Imaging plane;

[0018] A1: Object side;

[0019] A2: Image side;

[0020] BL: Cemented Lens

[0021] I: optical axis. Detailed Implementation

[0022] Reference FIG. 1A This diagram illustrates an imaging lens according to a first embodiment of the present invention. The imaging lens 10 of the first embodiment of the present invention includes, sequentially along the optical axis I of the imaging lens 10 from the object side A1 to the image side A2, an aperture 0, lenses 1 to 7, and a filter 8. Lens 1 is a spherical lens, lens 2 is a droplet lens, and lenses 1 and 2 are cemented together to form a cemented lens BL. When light emitted from an object to be photographed enters the imaging lens 10 and sequentially passes through the aperture 0, lenses 1, 2, 3, 4, 5, 6, 7, and filter 8, an image is formed on the image plane 99. The filter 8 is, for example, an infrared cut-off filter, which allows light of appropriate wavelengths (e.g., infrared or visible light) to pass through while filtering out the desired infrared band. The filter 8 is disposed between lens 7 and the image plane 99. To clarify, object side A1 is the side facing the object to be photographed, while image side A2 is the side facing the imaging plane 99.

[0023] In the present embodiment, the lens 1, the lens 2, the lens 3, the lens 4, the lens 5, the lens 6, the lens 7 and the filter 8 of the imaging lens 10 each have a material side 15, 25, 35, 45, 55, 65, 75, 85 facing the object side A1 and passing the imaging light, and a material side 16, 26, 36, 46, 56, 66, 76, 86 facing the image side A2 and passing the imaging light. The lens 1 and the lens 2 are bonded by the material side 16 of the lens 1 and the material side 25 of the lens 2 to form a bonded lens BL having positive refracting power. In the present embodiment, the aperture 0 is arranged on the object side A1 of the lens 1.

[0024] It should be noted that the present embodiment combines the liquid lens and the solid lens to form the bonded lens BL, mainly utilizes the high plasticity of the liquid lens to elastically adjust the optical characteristics such as the refractive index, the surface shape and the radius of curvature of the bonded lens BL, and breaks through the manufacturing limitation of the traditional solid lens.

[0025] According to the present embodiment, the refractive index of the spherical lens 1 falls within the range of 1.5 to 1.96, the liquid lens 2 can include a UV resin, the refractive index falls within the range of 1.5 to 1.62, and the diameter of the liquid lens 2 falls within the range of 1.0 mm to 6.0 mm. However, the present application is not limited thereto, and in other embodiments, other liquid lenses with high plasticity can be used to manufacture the liquid lens 2.

[0026] The bonded lens BL has positive refracting power, the optical axis area of the material side 15 is convex, the optical axis area of the material side 26 is concave, the material side 15 is a spherical surface, and the material side 26 is an aspheric surface. Specifically, by bonding the liquid lens 2 on the spherical lens 1 which is easier to manufacture, the aspheric material side 26 is generated, and the bonded lens BL with aspheric surface is generated, which greatly reduces the difficulty of manufacturing the aspheric lens in the traditional way.

[0027] The lens 3 has negative refracting power, the optical axis area of the material side 35 is convex, the optical axis area of the material side 36 is concave, and both the material side 35 and the material side 36 are aspheric surfaces.

[0028] The lens 4 has positive refracting power, the optical axis area of the material side 45 is convex, the optical axis area of the material side 46 is concave, and both the material side 45 and the material side 46 are aspheric surfaces.

[0029] The lens 5 has negative refracting power, the optical axis area of the material side 55 is convex, the optical axis area of the material side 56 is concave, and both the material side 55 and the material side 56 are aspheric surfaces.

[0030] Lens 6 has positive refractive power, the optical axis area of object side surface 65 is convex, the optical axis area of image side surface 66 is convex, and both object side surface 65 and image side surface 66 are aspherical surfaces.

[0031] Lens 7 has negative refractive power, the optical axis area of object side surface 75 is concave, the optical axis area of image side surface 76 is concave, and both object side surface 75 and image side surface 76 are aspherical surfaces.

[0032] Other detailed optical data of the first embodiment are shown in Table 1, and the full field of view (FOV) of the taking lens 10 is 80°.

[0033] Table 1:

[0034]

[0035] In Table 1, the interval of object side surface 15 (0.440 mm in Table 1) is the thickness of lens 1 on the optical axis I, the interval of image side surface 16 (0.100 mm in Table 1) is the thickness of lens 2 on the optical axis I, the interval of image side surface 26 (0.100 mm in Table 1) is the distance between image side surface 26 of lens 2 and object side surface 35 of lens 3 on the optical axis I, that is, the gap between the cemented lens BL and lens 3 on the optical axis I, and so on.

[0036] As shown in Table 1, the thickness of the droplet lens 2 is 0.100 mm, but the present application is not limited thereto, and in some embodiments, the thickness of the droplet lens 2 can be reduced as the refractive index thereof is increased, and the thickness of the droplet lens 2 can be less than 0.100 mm.

[0037] In addition, since the droplet lens has high plasticity, the radius of curvature of the image side surface 26 of the droplet lens 2 (7.638 mm in Table 1) can be different from the radius of curvature of the image side surface 16 of the spherical lens 1 (30.657 in Table 1), so that the cemented lens BL can have an aspherical image side surface 26 with a radius of curvature of 7.638 mm. In other words, the radius of curvature of the object side surface 25 of the droplet lens 2 can be different from the radius of curvature of the image side surface 26 thereof. However, the present application is not limited thereto, and in some embodiments, the radius of curvature of the object side surface 25 of the droplet lens 2 is the same as the radius of curvature of the image side surface 26 thereof.

[0038] In the present embodiment, the object side surfaces 35, 45, 55, 65, 75 of the lenses 3, 4, 5, 6, 7 and the image side surfaces 26, 36, 46, 56, 66, 76 of the lenses 2, 3, 4, 5, 6, 7 are all aspherical surfaces, and these aspherical surfaces are defined according to the following formula (1):

[0039]

[0040] Y: The distance between a point on the aspherical curve and the optical axis;

[0041] Z: Aspherical depth, which is the perpendicular distance between a point on the aspherical surface that is a distance Y from the optical axis and a tangent plane that is tangent to the vertex on the optical axis of the aspherical surface.

[0042] R: Radius of curvature of the lens surface;

[0043] K: Conic coefficient;

[0044] a 2i : The second-order aspherical coefficient.

[0045] In this embodiment, the conic coefficient K of the aspherical surface in formula (1) and various aspherical coefficients are shown in Table 2. In Table 2, number 26 indicates that it is the aspherical coefficient of the image side 26 of lens 2, and the other numbers follow the same pattern.

[0046] Table 2:

[0047] Surface K [a4] [a6] [a8] a 10 ]]> 26 0.00E+00 -2.35E-02 1.98E-02 5.62E-03 -9.44E-03 35 0.00E+00 -5.05E-02 1.92E-02 1.30E-01 -2.74E-01 36 0.00E+00 -1.25E-02 -7.16E-02 3.74E-01 -7.00E-01 45 0.00E+00 -1.54E-02 -1.47E-01 3.54E-01 -6.41E-01 46 0.00E+00 -2.95E-01 -3.72E-02 4.99E-03 6.28E-03 55 0.00E+00 -5.48E-01 -4.27E-02 -8.64E-03 -2.59E-03 56 0.00E+00 -5.83E-01 1.63E-01 2.96E-02 8.27E-03 65 0.00E+00 -3.57E-01 1.14E-02 -2.34E-02 1.99E-02 66 0.00E+00 -1.09E-01 2.73E-02 -7.07E-02 1.36E-02 75 0.00E+00 -1.04E-01 2.78E-01 -7.64E-02 -6.81E-03 76 0.00E+00 -1.01E+00 2.48E-01 -5.76E-02 -2.82E-02 Surface a 12 ]]> a 14 ]]> a 16 ]]> a 18 ]]> a 20 ]]> 26 -7.61E-03 4.61E-03 0.00E+00 0.00E+00 0.00E+00 35 2.73E-01 -1.45E-01 3.27E-02 0.00E+00 0.00E+00 36 7.35E-01 -4.12E-01 9.92E-02 0.00E+00 0.00E+00 45 6.67E-01 -3.93E-01 1.02E-01 0.00E+00 0.00E+00 46 3.40E-03 1.08E-03 2.23E-04 0.00E+00 0.00E+00 55 -9.96E-04 1.15E-04 -8.33E-05 0.00E+00 0.00E+00 56 -2.27E-03 -2.38E-03 -2.66E-03 0.00E+00 0.00E+00 65 -4.66E-03 2.29E-03 3.67E-03 3.15E-03 -9.49E-04 66 1.76E-02 7.32E-03 5.97E-03 4.80E-03 1.69E-03 75 1.14E-02 -6.27E-03 3.55E-03 -2.16E-03 4.88E-04 76 -2.75E-02 2.89E-04 1.19E-02 6.03E-03 2.19E-03

[0048] See also FIGS. 1B-1D , FIG. 1B The diagram shows the field curvature aberration in the sagittal direction when light with wavelengths of 470 nm, 510 nm, 555 nm, 610 nm, and 650 nm is incident on the imaging lens 10 of the first embodiment. FIG. 1C The graph shows the field curvature aberration in the meridional direction when light with wavelengths of 470 nm, 510 nm, 555 nm, 610 nm, and 650 nm is incident on the imaging lens 10 of the first embodiment. FIG. 1D The graph shows the distortion curves when light with wavelengths of 470 nm, 510 nm, 555 nm, 610 nm and 650 nm is incident on the imaging lens 10 of the first embodiment.

[0049] exist FIG. 1B as well as FIG. 1C In the two field curvature aberration curves shown, the field curvature aberrations of the five representative wavelengths fall within ±0.20 mm across the entire field of view, indicating that the imaging lens 10 of the first embodiment of the present invention can effectively eliminate aberrations. FIG. 1D In the distortion curve diagram shown, the distortion aberration of the five representative wavelengths is less than 3.4407% across the entire field of view, indicating that the imaging lens 10 of the first embodiment of the present invention has good imaging quality.

[0050] To fully illustrate the various embodiments of the present application, other embodiments of the present application will be described hereinafter. It must be noted here that the following embodiments use the element numbers and parts of the foregoing embodiments, wherein the same numbers are used to represent the same or similar elements, and the description of the same technical content is omitted. The description of the omitted parts can be referred to the foregoing embodiments, which will not be repeated hereinafter.

[0051] Referring to FIG. 2A FIG. 2 shows a schematic diagram of an image pickup lens according to a second embodiment of the present application. The image pickup lens 10 of the second embodiment of the present application sequentially includes lenses 1 to 4, an aperture 0, a lens 5, a lens 6, and a filter 8 from an object side Al to an image side A2 along an optical axis I of the image pickup lens 10. The lens 1 is a liquid lens, the lens 2 is a spherical lens, and the lens 1 and the lens 2 are cemented as a cemented lens BL. When a light ray emitted from an object to be photographed enters the image pickup lens 10 and sequentially passes through the lens 1, the lens 2, the lens 3, the lens 4, the aperture 0, the lens 5, the lens 6, and the filter 8, an image is formed on an imaging surface 99. The filter 8 is disposed between the lens 6 and the imaging surface 99.

[0052] In the present embodiment, the lens 1, the lens 2, the lens 3, the lens 4, the lens 5, the lens 6, and the filter 8 of the image pickup lens 10 each have an object side surface 15, 25, 35, 45, 55, 65, 85 facing the object side Al and passing the imaging light ray and an image side surface 16, 26, 36, 46, 56, 66, 86 facing the image side A2 and passing the imaging light ray, wherein the lens 1 and the lens 2 are cemented by the image side surface 16 of the former and the object side surface 25 of the latter to form the cemented lens BL having positive refractive power.

[0053] The cemented lens BL has positive refractive power, the optical axis region of the object side surface 15 is a convex surface, the optical axis region of the image side surface 26 is a concave surface, the object side surface 15 is an aspherical surface, and the image side surface 26 is a spherical surface. Specifically, by cementing the liquid lens 1 on the spherical lens 2 which is easier to mold, the object side surface 15 of the aspherical surface is generated, and the cemented lens BL of the aspherical surface is generated.

[0054] The lens 3 has positive refractive power, the optical axis region of the object side surface 35 is a convex surface, the optical axis region of the image side surface 36 is a convex surface, and both the object side surface 35 and the image side surface 36 are aspherical surfaces.

[0055] The lens 4 has negative refractive power, the optical axis region of the object side surface 45 is a concave surface, the optical axis region of the image side surface 46 is a concave surface, and both the object side surface 45 and the image side surface 46 are aspherical surfaces.

[0056] The lens 5 has positive refractive power, the optical axis region of the object side surface 55 is a concave surface, the optical axis region of the image side surface 56 is a convex surface, and both the object side surface 55 and the image side surface 56 are aspherical surfaces.

[0057] Lens 6 has positive refractive power. Its object-side surface 65 has a convex optical axis region, and its image-side surface 66 has a concave optical axis region. Both the object-side surface 65 and the image-side surface 66 are aspherical.

[0058] Other detailed optical data for the second embodiment are shown in Table 3. The full field of view of the imaging lens 10 is 34.3°.

[0059] Table 3:

[0060]

[0061] In Table 3, the spacing of the object side 15 (0.100 mm as shown in Table 3) is the thickness of lens 1 on optical axis I, the spacing of the object side 25 (0.709 mm as shown in Table 3) is the thickness of lens 2 on optical axis I, the spacing of the image side 26 (2.274 mm as shown in Table 3) is the distance between the image side 26 of lens 2 and the object side 35 of lens 3 on optical axis I, which is the gap between the cemented lens BL and lens 3 on optical axis I, and so on.

[0062] In this embodiment, the object surfaces 15, 35, 45, 55, and 65 of lenses 1, 3, 4, 5, and 6, as well as the image surfaces 36, 46, 56, and 66 of lenses 3, 4, 5, and 6, are all aspherical surfaces, and these aspherical surfaces are defined according to formula (1).

[0063] In this embodiment, the conic coefficient K of the aspherical surface in formula (1) and various aspherical coefficients are shown in Table 4. In Table 4, number 15 indicates that it is the aspherical coefficient of the object surface 15 of lens 1, and the other numbers follow the same pattern.

[0064] Table 4:

[0065]

[0066] See also FIGS. 2B-2D , FIG. 2B The diagram shows the field curvature aberration in the sagittal direction when light with wavelengths of 470 nm, 510 nm, 555 nm, 610 nm, and 650 nm is incident on the imaging lens 10 of the second embodiment. FIG. 2C The graph shows the field curvature aberration in the meridional direction when light with wavelengths of 470 nm, 510 nm, 555 nm, 610 nm, and 650 nm is incident on the imaging lens 10 of the second embodiment. FIG. 2D The graph shows the distortion curves when light with wavelengths of 470 nm, 510 nm, 555 nm, 610 nm and 650 nm is incident on the imaging lens 10 of the second embodiment.

[0067] In FIG. 2B and FIG. 2C The field curvature aberration curves of the five representative wavelengths in the entire field of view range are within ±0.10 mm, which indicates that the imaging lens 10 of the second embodiment of the present application can effectively eliminate aberration. FIG. 2D The distortion curves of the five representative wavelengths in the entire field of view range are less than 2.3224%, which indicates that the imaging lens 10 of the second embodiment of the present application has good imaging quality.

[0068] Referring to FIG. 3A , which shows a schematic diagram of an imaging lens according to a third embodiment of the present application. The imaging lens 10 of the third embodiment of the present application comprises, in order from the object side Al to the image side A2 along the optical axis I of the imaging lens 10, a lens 1, an aperture 0, a lens 2 to a lens 6, and a filter 8. The lens 2 is a liquid drop lens, the lens 3 is a spherical lens, and the lens 2 and the lens 3 are cemented as a cemented lens BL. After the light emitted by an object to be photographed enters the imaging lens 10 and sequentially passes through the lens 1, the aperture 0, the lens 2, the lens 3, the lens 4, the lens 5, the lens 6, and the filter 8, an image is formed on the imaging surface 99. The filter 8 is arranged between the lens 6 and the imaging surface 99.

[0069] In the present embodiment, the lens 1, the lens 2, the lens 3, the lens 4, the lens 5, the lens 6, and the filter 8 of the imaging lens 10 each have an object side surface 15, 25, 35, 45, 55, 65, 85 facing the object side Al and passing the imaging light, and an image side surface 16, 26, 36, 46, 56, 66, 86 facing the image side A2 and passing the imaging light, wherein the lens 2 and the lens 3 are cemented by the image side surface 26 of the former and the object side surface 35 of the latter to form the cemented lens BL having positive refractive power.

[0070] The lens 1 has negative refractive power, the optical axis region of the object side surface 15 is concave, the optical axis region of the image side surface 16 is concave, and the object side surface 35 and the image side surface 36 are both aspherical surfaces.

[0071] The cemented lens BL has positive refractive power, the optical axis region of the object side surface 25 is convex, the optical axis region of the image side surface 36 is convex, the object side surface 25 is an aspherical surface, and the image side surface 36 is a spherical surface. Specifically, by cementing the liquid drop lens 2 on the spherical lens 3 which is easier to mold, the aspherical object side surface 25 is generated, and the aspherical cemented lens BL is generated.

[0072] The lens 4 has negative refractive power, the optical axis region of the object side surface 45 is convex, the optical axis region of the image side surface 46 is concave, and the object side surface 45 and the image side surface 46 are both aspherical surfaces.

[0073] Lens 5 has positive refractive power, the optical axis area of object side surface 55 is concave, the optical axis area of image side surface 56 is convex, and both object side surface 55 and image side surface 56 are aspherical surfaces.

[0074] Lens 6 has negative refractive power, the optical axis area of object side surface 65 is convex, the optical axis area of image side surface 66 is concave, and both object side surface 65 and image side surface 66 are aspherical surfaces.

[0075] Other detailed optical data of the third embodiment are shown in Table 5, and the full field angle of the image pickup lens 10 is 110.0°.

[0076] Table 5:

[0077]

[0078]

[0079] In Table 5, the interval of object side surface 15 (0.322 mm in Table 5) is the thickness of lens 1 on the optical axis I, the interval of image side surface 16 (0.688 mm in Table 5) is the distance between image side surface 16 of lens 1 and aperture 0 on the optical axis I. The interval of aperture 0 (0.138 mm in Table 5) is the distance between aperture 0 and object side surface 25 of lens 2 on the optical axis I, and so on.

[0080] In the present embodiment, object side surfaces 15, 25, 45, 55, 65 of lens 1, lens 2, lens 4, lens 5, lens 6 and image side surfaces 16, 46, 56, 66 of lens 1, lens 4, lens 5, lens 6 are aspherical surfaces, and these aspherical surfaces are defined by formula (1).

[0081] The conic coefficients K and the aspherical coefficients of the aspherical surfaces in formula (1) of the present embodiment are shown in Table 6. In Table 6, No. 15 represents the aspherical coefficients of object side surface 15 of lens 1, and other numbers are defined in the same way.

[0082] Table 6:

[0083]

[0084]

[0085] In addition, referring to FIGS. 3B-3D , FIG. 3B Figures showing the curve of the field curvature aberration in the sagittal direction when the light with wavelengths of 470 nm, 510 nm, 555 nm, 610 nm and 650 nm respectively enters the image pickup lens 10 of the third embodiment, FIG. 3CThe graph shows the field curvature aberration in the meridional direction when light with wavelengths of 470 nm, 510 nm, 555 nm, 610 nm, and 650 nm is incident on the imaging lens 10 of the third embodiment. FIG. 3D The graph shows the distortion curves when light with wavelengths of 470 nm, 510 nm, 555 nm, 610 nm and 650 nm is incident on the imaging lens 10 of the third embodiment.

[0086] exist FIG. 3B as well as FIG. 3C In the two field curvature aberration curves shown, the field curvature aberrations of the five representative wavelengths fall within ±0.20 mm across the entire field of view, indicating that the imaging lens 10 of the third embodiment of the present invention can effectively eliminate aberrations. FIG. 3D In the distortion curve diagram shown, the distortion aberration of the five representative wavelengths is less than 2.5880% across the entire field of view, indicating that the imaging lens 10 of the third embodiment of the present invention has good imaging quality.

[0087] In summary, the imaging lens provided in this embodiment of the invention combines a droplet lens and a solid lens to form a cemented lens. It mainly utilizes the high plasticity of the droplet lens to flexibly adjust the overall refractive index, surface shape, and radius of curvature of the cemented lens, thus breaking through the manufacturing limitations of traditional solid lenses.

Claims

1. An image-capturing lens, characterized in that, It includes a cemented lens, a first lens, a second lens, a third lens, and a fourth lens arranged sequentially from the object side to the image side, wherein... The cemented lens has positive refractive power and is composed of a spherical lens and a droplet lens. The imaging lens consists of four lenses, excluding the cemented lens which has refractive power. The first lens, the second lens, the third lens, and the fourth lens respectively have positive refractive power, negative refractive power, positive refractive power, and positive refractive power.

2. The imaging lens according to claim 1, characterized in that, The droplet lens comprises UV resin.

3. The imaging lens according to claim 1, characterized in that, The droplet lens includes an aspherical profile.

4. The imaging lens according to claim 1, characterized in that, The refractive index of the spherical lens falls in the range of 1.5 to 1.96, and the refractive index of the droplet lens falls in the range of 1.5 to 1.

62.

5. The imaging lens according to claim 1, characterized in that, The thickness of the droplet lens along the optical axis is less than or equal to 0.100 mm.

6. The imaging lens according to claim 1, characterized in that, The radius of curvature of the object side of the droplet lens is different from the radius of curvature of the image side.

7. An image-capturing lens, characterized in that, It includes a cemented lens, a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged sequentially from the object side to the image side, wherein... The cemented lens has positive refractive power and is composed of a spherical lens and a droplet lens. The imaging lens consists of five lenses, excluding the cemented lens which has refractive power. The first lens, the second lens, the third lens, the fourth lens, and the fifth lens respectively have negative refractive power, positive refractive power, negative refractive power, positive refractive power, and negative refractive power.

8. An image-capturing lens, characterized in that, It includes a first lens, a cemented lens, a second lens, a third lens, and a fourth lens arranged sequentially from the object side to the image side, wherein... The cemented lens has positive refractive power and is composed of a spherical lens and a droplet lens. The imaging lens consists of four lenses, excluding the cemented lens which has refractive power. The first lens, the second lens, the third lens, and the fourth lens respectively have negative refractive power, negative refractive power, positive refractive power, and negative refractive power.

Images