KR102150717B1 - Image pickup lens - Google Patents

Abstract

The embodiment includes: a first lens having a positive power arrangement from an object side to an imaging side, and having a convex shape on the water side; + Or-a second lens having a power arrangement; + Or-a third lens with power placement; + A fourth lens having a power arrangement and a convex image side; And a fifth lens having a concave shape on the water side, wherein at least one of the first lens and the second lens is formed of a glass material, and the power of the second lens and the power of the third lens Provides imaging lenses having powers of different signs.

Description

Imaging lens {IMAGE PICKUP LENS}

The present invention relates to a five-element imaging lens.

In recent years, conventional film cameras include camera modules for portable terminals using small solid-state imaging elements such as CCD and CMOS, digital still cameras (DSCs), camcorders, PC cameras (imaging devices attached to personal computers), and the like. Is being replaced, and such an imaging device is mounted on various electronic products.

In such an environment, the imaging lens provided in the imaging device by various components included in the electronic product is provided as a plastic lens in consideration of processing precision and cost.

However, in the conventional active lens, since the refractive index may change due to a change in temperature over time due to plastic characteristics, a focal length or a post focal length may change.

The embodiment intends to implement an imaging lens to compensate for changes over time according to temperature changes.

The embodiment includes: a first lens having a positive power arrangement from an object side to an imaging side, and having a convex shape on the water side; + Or-a second lens having a power arrangement; + Or-a third lens with power placement; + A fourth lens having a power arrangement and a convex image side; And a fifth lens having a concave shape on the water side, wherein at least one of the first lens and the second lens is formed of a glass material, and the power of the second lens and the power of the third lens Provides imaging lenses having powers of different signs.

In addition, the first lens and the second lens may be formed of a glass material.

In addition, the first lens may be formed of a glass mold lens.

In addition, the first lens may have a meniscus shape or a convex shape on both sides.

In addition, the second lens may have a meniscus shape, a convex shape on both sides, or a concave shape on both sides.

Further, the third lens may have a meniscus shape or a concave shape on both sides.

In addition, the fourth lens may have a meniscus shape or a convex shape on both sides.

Also, the fifth lens may have a meniscus shape or a concave shape on both sides.

In addition, at least one of the first to fifth lenses may have one or both surfaces aspherical.

In addition, it may further include a stop provided in front of the water side of the first lens.

In addition, the imaging lens may satisfy the first conditional expression 0.8 <N ₁ /N ₂ <1. Here, N ₁ is the refractive index of the first lens, and N ₂ is the refractive index of the second lens.

In addition, the imaging lens may satisfy the second conditional expression 0.8 <N ₃ /N ₂ <1. Here, N ₂ is the refractive index of the second lens, and N ₃ is the refractive index of the third lens.

In addition, the imaging lens may satisfy the third conditional expression 1 <V ₁ /V ₃ <1.5. Here, V ₁ is the Abbe number of the first lens, and V ₃ is the Abbe number of the third lens.

In addition, the imaging lens may satisfy the fourth conditional expression 0 <V ₂ /V ₃ <2. Here, V ₂ is the Abbe number of the second lens, and V ₃ is the Abbe number of the third lens.

In addition, the imaging lens may satisfy the fifth conditional expression 10 <|V ₁ -V ₃ |< 35. Here, V ₁ is the Abbe number of the first lens, and V ₃ is the Abbe number of the third lens.

In addition, the imaging lens may satisfy the sixth conditional expression 10 <|V ₂ -V ₃ |> 35. Here, V ₂ is the Abbe number of the second lens, and V ₃ is the Abbe number of the third lens.

In addition, the imaging lens may satisfy the seventh conditional expression 0.1 <f/f ₁ <1.5. Here, f is the focal length of the entire optical system, and f ₁ is the focal length of the first lens.

In addition, the imaging lens may satisfy the eighth conditional expression 0.8 <f/f ₄ <1.7. Here, f is the focal length of the entire optical system, and f ₄ is the focal length of the fourth lens.

In addition, the imaging lens may satisfy the ninth conditional expression 0 <│R ₁ /R ₂ │< 1. Here, R ₁ denotes a radius of curvature of the object side surface of the first lens, and R ₂ denotes a radius of curvature of the image side surface of the first lens.

In addition, the imaging lens may satisfy the tenth conditional expression 1 <|R ₇ /R ₈ |<25. Here, R ₇ denotes a radius of curvature of the object side surface of the fourth lens, and R ₈ denotes a radius of curvature of the image side surface of the fourth lens.

The imaging lens according to the present invention can achieve excellent performance even in an FF-type imaging device since changes over time according to temperature changes are reduced.

1 is a configuration diagram of an imaging lens module according to a first embodiment of the present invention.
2 is a configuration diagram of an imaging lens module according to a second embodiment of the present invention.
3 is a configuration diagram of an imaging lens module according to a third embodiment of the present invention.
4 is a configuration diagram of an imaging lens module according to a fourth embodiment of the present invention.
5 is a graph showing an aberration diagram according to the first embodiment of the present invention shown in FIG.
6 is a graph showing an aberration diagram according to the second embodiment of the present invention shown in FIG. 2.
7 is a graph showing an aberration diagram according to the third embodiment of the present invention shown in FIG. 3.
8 is a graph showing an aberration diagram according to the fourth embodiment of the present invention shown in FIG. 4.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Unless otherwise defined, all terms in the present specification are the same as the general meanings of terms understood by those skilled in the art, and if terms used in the present specification conflict with the general meanings of the terms, the definitions used in the present specification are applied.

However, the invention to be described below is only for describing an embodiment of the present invention, not for limiting the scope of the present invention, and reference numerals used identically throughout the specification denote the same elements.

In addition, in describing the configuration of each lens in the present invention, the "object side" refers to the surface of the lens facing the object side with respect to the optical axis, and the "image side" refers to the optical axis. It refers to the surface of the lens facing the image side as a reference.

In addition, with respect to the features of each embodiment, each of the four lens types will be described below with reference to FIGS. 1 to 4, and then, aberration diagrams according to each lens type will be detailed with reference to FIGS. Explain clearly.

1 is a configuration diagram of an imaging lens module according to a first embodiment of the present invention.

Referring to FIG. 1, the imaging lens according to the first embodiment of the present invention includes a first lens 10, a second lens 20, a third lens 30, and a fourth lens 40 from an object side to an imaging side. And the fifth lens 50 in order, and may further include a stop, a filter 60 and a light receiving element 70.

In Figure 1, 'S _1' are the water-side surface of the first lens (10) of the water side, 'it S _2' of the first lens, in which a side of 10, 'S _3' of the second lens 20, 'S _4' has a second and a side surface of the lens (20), 'S _5' are first and the image-side surface of the water side, 'S _6' of the third lens 30 has a third lens 30, 'it S ₇ 'Is the water side of the fourth lens 40,'S ₈ ' is the image side of the fourth lens 40,'S _9'is the water side of the fifth lens 50, and'S ₁₀ ' is the fifth. This is the image side of the lens 50.

Reference numerals 10 to 70 and'S _x'of these components may be equally applied to other embodiments shown in FIGS. 2 and 3 of the present invention.

Referring to FIG. 1, the first lens 10 according to the first embodiment of the present invention has a convex shape on the water side, and the second lens 20 to the fourth lens 40 have a convex shape on the image side. And, the fifth lens 50 may be implemented in a concave shape on the water side.

Specifically, the first lens 10 may have a convex or concave shape on the image side, and may also have a meniscus shape convex toward the water side or a double convex shape.

The second lens 20 may have a double convex shape, a double concave shape, or a meniscus shape, and may also have a meniscus shape convex toward the water side.

The third lens 30 may have a double convex shape, a double concave shape, or a meniscus shape, and may have a meniscus shape that is convex toward the water or toward the image. In addition, the third lens 30 may have an inflection point on at least one surface of the water side or the image side.

The fourth lens 40 may have a convex or concave shape on the water side, and may have a meniscus shape or both convex shapes that are convex upward. In addition, the fourth lens 40 may have an inflection point on at least one surface of the water side or the image side.

The fifth lens 50 may have a convex or concave shape on an image side, and may have a meniscus shape or both concave shape that is convex upward. In addition, the fifth lens 50 may have at least one inflection point on at least one surface of the water side or the image side.

The lens shape represents a shape in the optical axis or in the vicinity of the optical axis.

In addition, the first lens 10 has a + power arrangement, the second lens 20 has a + power arrangement, the third lens 30 has a-power arrangement, and the fourth lens 40 ) Has a + power arrangement, and the fifth lens 50 has a-power arrangement.

On the other hand, having the power arrangement of +, +, -, +,-in the order of the first lens 10 to the fifth lens 50 as described above takes into account the optical performance of the imaging lens, manufacturing cost, and miniaturization of the imaging device. This is the optimal power arrangement that has been set.

In addition, one of the first lens 10 or the third lens 30 may have the lowest power among a total of five lenses. That is, the power of the first lens 10 may be the smallest or the power of the third lens 30 may be the smallest. When expressed as a focal length, the focal length of the first lens 10 may be the longest or the focal length of the third lens 30 may be the longest.

In addition, the fifth lens 50 may be preferably formed in a convex shape in the vicinity of the optical axis and a concave and convex shape toward the periphery in the vicinity of the optical axis, and it may be preferable in securing the image surface curvature and telecentricity, and the center of the image-side surface ( From the vicinity of the optical axis) to the periphery, the angle of incidence of the light beam can be made close to normal to the lens.

At least one of the first to fifth lenses 10 to 50 is preferably one or both aspherical surfaces. This is because, when an aspherical surface is formed on at least one or more of the first to fifth lenses 50, it has excellent effects in correcting various aberrations, particularly spherical aberration, coma aberration, and distortion aberration.

In addition, at least one of the first to fifth lenses 10 to 50 may be provided as a glass lens. That is, in the design of the optical system, any one of the first lens 10 or the second lens 20, which can be formed of glass while affecting optical properties, may be formed as a glass lens. In addition, both the first lens 10 and the second lens 20 may be formed of glass. In addition, lenses other than the first and second lenses 10 and 20 may be formed of glass. In this way, the focal length and post focal length can be minimized by using a glass lens. Therefore, it may be applicable to a fixed focus (F.F) type that does not move the lens group, that is, a type without a separate focus adjustment means. In addition, when the lens is made of glass, the transmittance of the lens can be increased and the image can be made clear and clear.

This is because the glass lens has a relatively high transition point, so that the deformation of the refractive index and the focal length are small even with the aging change according to the temperature change. The imaging device provided inside the electronic device is exposed by the ambient temperature. For example, when the ambient temperature of the imaging lens implemented with a plastic lens is 60°C, the back focal length changes 20 ~ 30 µm. In this case, the subject The distance changes to a short distance. However, when at least one glass lens is disposed as in the above embodiment, when the ambient temperature is 60° C., the back focal length is changed to less than 10 μm, so that even in the F.F (Fixed Focusing) type, excellent reliability may be obtained.

In addition, unlike a plastic lens, such a glass lens may be formed so that an inflection point may not exist, but in the case of being formed in a glass mold method, an inflection point may exist.

The lens according to the embodiments of the present invention may include a case where the surface is coated to prevent reflection or improve surface hardness.

On the other hand, the aperture is preferably located on the object side of the first lens 10 to the fifth lens 50 to ensure telecentricity, and is also in front of the water side of the first lens 10 Although it may be located, it may be designed to be disposed between the second lens 20 and the third lens 30 or between the first lens 10 and the second lens 20.

On the other hand, the filter 60 is an optical member, for example, a cover glass for protecting an image surface, an optical member in the shape of a flat plate such as an infrared filter (Infrared Ray Filter) is disposed, and the light receiving element 70 may be an image sensor.

Meanwhile, the first embodiment may satisfy any one or some of the following conditional expressions, or a combination thereof.

<Conditional Expression 1>

0.8 <N ₁ /N ₂ <1

Here, N ₁ is the refractive index of the first lens, and N ₂ is the refractive index of the second lens.

<Conditional Expression 2>

0.8 <N ₃ /N ₂ <1

Here, N ₂ is the refractive index of the second lens, and N ₃ is the refractive index of the third lens.

<Conditional Expression 3>

1 <V ₁ /V ₃ <1.5

Here, V ₁ is the Abbe number of the first lens, and V ₃ is the Abbe number of the third lens.

<Conditional Expression 4>

0 <V ₂ /V ₃ <2

Here, V ₂ is the Abbe number of the second lens, and V ₃ is the Abbe number of the third lens.

<Conditional Expression 5>

10 <│V ₁ -V ₃ │< 35

Here, V ₁ is the Abbe number of the first lens, and V ₃ is the Abbe number of the third lens.

<Conditional Expression 6>

10 <│V ₂ -V ₃ │>35

Here, V ₂ is the Abbe number of the second lens, and V ₃ is the Abbe number of the third lens.

<Conditional Expression 7>

0.1 <f/f ₁ <1.5

Here, f is the focal length of the entire optical system, and f ₁ is the focal length of the first lens.

<Conditional Expression 8>

0.8 <f/f ₄ <1.7

Here, f is the focal length of the entire optical system, and f ₄ is the focal length of the fourth lens.

<Conditional Expression 9>

0 <│R ₁ /R ₂ │< 1

Here, R ₁ denotes a radius of curvature of the object side surface of the first lens, and R ₂ denotes a radius of curvature of the image side surface of the first lens.

<Conditional Expression 10>

1 <│R ₇ /R ₈ │ <25

Here, R ₇ denotes a radius of curvature of the object side surface of the fourth lens, and R ₈ denotes a radius of curvature of the image side surface of the fourth lens.

Conditional Equation 7 as described above defines a condition range for the first lens 10 having relatively weak power to exclude performance degradation mainly due to manufacturing errors. Specifically, when exceeding the above range, the power of the first lens 10 becomes strong, so that each aberration generated by the first lens 10 increases, and the second lenses 20 to the fifth lenses ( 50) After this, the burden of correcting aberration increases.

Conditional Equation 8 as described above defines a condition range for the fourth lens 40 having a relatively strong power to exclude performance deterioration mainly due to manufacturing errors, and to exclude performance degradation due to coma aberration. Specifically, if it exceeds the above range, the power balance between each lens is broken, and it becomes difficult to realize the miniaturization and high performance of the imaging lens.

By satisfying each of the above Conditional Expressions 9 or 10, aberration correction is performed for each angle of view for each lens. That is, as the incident angle of the light beam in the imaging device is controlled to a certain angle, the light amount imbalance on the image side can be reduced.

Specifically, when the range of Conditional Expression 9 is satisfied, it is advantageous for miniaturization of the imaging lens, and specifically, the imaging lens limited for miniaturization by making the radius of curvature of the water side of the first lens 10 smaller than the image side. The degree of freedom of the rest of the lens curvature can be further increased at the total length of.

This is because when the range of Conditional Expression 10 is satisfied, it is easy to implement a shape that allows incident light to enter the surface of the fourth lens 40 in a tangential direction, thereby reducing the occurrence of aberrations.

The imaging lens according to the first exemplary embodiment of the present invention illustrated in FIG. 1 having such characteristics may have specific characteristics as shown in Tables 1 to 3 below.

Here, Table 1 shows lens data of each lens surface.

S _x Radius of curvature (R) Thickness or distance (d) Refractive index (N) Abbesu (vd) One 2.3440 0.405485068 1.536 60.3 2 3.0853 0.224911453 3 3.4355 0.82586602 1.621 60.1 4 -5.2670 0.23489861 5 -4.3139 0.4 1.704 29.9 6 8.8312 0.706821371 7 48.0723 0.75029156 1.536 56.5 8 -1.7271 0.68894118 9 -1.4784 0.4 1.536 56.5 10 -219.9215 0.203021137

Table 2 below is a focal length according to the first embodiment.

Focal length f 4.7 f ₁ 15.367325 f ₂ 3.460069 f ₃ -4.032481 f ₄ 3.142137 f ₅ -2.792

Table 3 below shows preferred specific values for each item.

Item value N ₃ /N ₁ 1.109375 N ₃ /N ₂ 1.051202961 V ₁ /V ₃ 2.016722408 V ₂ /V ₃ 2.010033445 │V ₁ -V ₃ │ 30.4 │V ₂ -V ₃ │ 30.2 f/f ₁ 0.30584373 f/f ₄ 1.495797287 │R ₁ /R ₂ │ 0.759751136 │R ₇ /R ₈ │ 27.83351557

On the other hand, FIG. 5 is a graph showing an aberration diagram according to the first embodiment of the present invention, showing longitudinal spherical aberration, astigmatic field curves, and distortion in order from the left. It is a graph.

In FIG. 5, the Y-axis means the size of the image, the X-axis means the focal length (in mm) and the degree of distortion (in %), and it is interpreted that as the curves approach the Y-axis, the aberration correction function is good. , In the imaging lens according to the first embodiment of the present invention, since values of images appear adjacent to the Y-axis in almost all fields, spherical aberration, astigmatism, and distortion aberration are all excellent.

2 is a configuration diagram of an imaging lens module according to a second embodiment of the present invention.

Referring to FIG. 2, the first lens 10 according to the second embodiment of the present invention has a convex shape on the water side, and the second to fourth lenses 40 have a convex shape on the image side, and the The fifth lens 50 may have a concave water-side shape.

In addition, the first lens 10 has a + power arrangement, the second lens 20 has a-power arrangement, the third lens 30 has a + power arrangement, and the fourth lens 40 ) Has a + power arrangement, and the fifth lens 50 has a-power arrangement.

On the other hand, having the power arrangement of +, -, +, +,-in order from the first lens 10 to the fifth lens 50 as described above takes into account the optical performance of the imaging lens, manufacturing cost, and miniaturization of the imaging device. This is the optimal power arrangement that has been set.

In addition, the fifth lens 50 is preferably formed in a concave shape in the vicinity of the optical axis and a convex shape toward the periphery in order to secure the curvature of the image surface and telecentricity, and from the center (near the optical axis) The angle of incidence of the light rays across the periphery can be made close to normal to the lens.

Meanwhile, in the imaging lens according to the second exemplary embodiment, any one or part of Conditional Equations 1 to 10 according to the first exemplary embodiment, a combination thereof, or all may be applied.

The imaging lens according to the second exemplary embodiment of the present invention illustrated in FIG. 2 having such characteristics may have specific characteristics as shown in Tables 4 to 6 below.

Here, Table 4 shows lens data of each lens surface.

S _x Radius of curvature (R) Thickness or distance (d) Refractive index (N) Abbesu (vd) One 2.5446 0.837423851 1.536 60.3 2 -3.8353 0.2 3 -9.9834 0.4 1.755 27.5 4 4.0021 0.336216773 5 3.7494 0.4 1.744 43.5 6 5.5595 0.622858562 7 -38.9194 0.695515594 1.536 56.5 8 -1.5659 0.43798522 9 -3.5223 0.4 1.536 56.5 10 1.8530 0.3

Table 5 below is a focal length according to the second embodiment.

Focal length f 4.7 f ₁ 3.005044 f ₂ -3.704989 f ₃ 14.05485 f ₄ 3.039138 f ₅ -2.21893

Table 6 below shows preferred specific values for each item.

Item value N ₃ /N ₁ 1.135416667 N ₃ /N ₂ 0.993732194 V ₁ /V ₃ 1.386206897 V ₂ /V ₃ 0.632183908 │V ₁ -V ₃ │ 16.8 │V ₂ -V ₃ │ 16 f/f ₁ 1.564036999 f/f ₄ 1.546491143 │R ₁ /R ₂ │ 0.663465643 │R ₇ /R ₈ │ 24.85381573

On the other hand, FIG. 6 is a graph showing an aberration diagram according to the second embodiment of the present invention, showing longitudinal spherical aberration, astigmatic field curves, and distortion in order from the left. It is a graph.

In FIG. 6, the Y-axis means the size of the image, the X-axis means the focal length (in mm) and the degree of distortion (in %), and it is interpreted that the aberration correction function is better as the curves approach the Y-axis. , In the imaging lens according to the second embodiment of the present invention, since values of images appear adjacent to the Y axis in almost all fields, spherical aberration, astigmatism, and distortion aberration are all excellent.

3 is a configuration diagram of an imaging lens module according to a third embodiment of the present invention.

Referring to FIG. 3, the first lens 10 according to the third embodiment of the present invention has a convex shape on the water side, and the second lens 20 to the fourth lens 40 have a convex shape on the image side. And, the fifth lens 50 may be implemented in a concave shape on the water side.

In addition, the first lens 10 has a + power arrangement, the second lens 20 has a-power arrangement, the third lens 30 has a + power arrangement, and the fourth lens 40 ) Has a + power arrangement, and the fifth lens 50 has a-power arrangement.

On the other hand, having the power arrangement of +, -, +, +,-in order from the first lens 10 to the fifth lens 50 as described above takes into account the optical performance of the imaging lens, manufacturing cost, and miniaturization of the imaging device. This is the optimal power arrangement that has been set.

In addition, the fifth lens 50 is preferably formed in a concave shape in the vicinity of the optical axis and a convex shape toward the periphery in order to secure the curvature of the image surface and telecentricity, and from the center (near the optical axis) The angle of incidence of the light rays across the periphery can be made close to normal to the lens.

Meanwhile, in the imaging lens according to the third embodiment, any one, part, or combination or all of Conditional Expressions 1 to 10 according to the first embodiment may be applied.

The imaging lens according to the third embodiment of the present invention illustrated in FIG. 3 having such characteristics may have specific characteristics as shown in Tables 7 to 9 below.

Here, Table 7 shows lens data of each lens surface.

S _x Radius of curvature (R) Thickness or distance (d) Refractive index (N) Abbesu (vd) One 2.5812 0.679435371 1.62 60.3 2 -4.2578 0.2 3 10.5147 0.4 1.755 27.5 4 2.5461 0.795706524 5 -3.0004 0.543570318 1.583 59.4 6 -1.7731 0.2 7 -5.6164 0.582722833 1.536 56.5 8 -1.3778 0.2 9 -8.4480 0.4 1.536 56.5 10 1.3064 0.3

Table 8 below is a focal length according to the third embodiment.

Focal length f 4.7 f ₁ 3.120617 f ₂ -4.508711 f ₃ 6.363177 f ₄ 3.266366 f ₅ -2.091325

Table 9 below shows preferred specific values for each item.

Item value N ₃ /N ₁ 0.977160494 N ₃ /N ₂ 0.901994302 V ₁ /V ₃ 1.015151515 V ₂ /V ₃ 0.462962963 │V ₁ -V ₃ │ 0.9 │V ₂ -V ₃ │ 31.9 f/f ₁ 1.506112413 f/f ₄ 1.438907948 │R ₁ /R ₂ │ 0.606234325 │R ₇ /R ₈ │ 4.076484698

Meanwhile, FIG. 7 is a graph showing an aberration diagram according to the third embodiment of the present invention, showing longitudinal spherical aberration, astigmatic field curves, and distortion in order from the left. It is a graph.

In FIG. 7, the Y axis means the size of the image, the X axis means the focal length (in mm) and the degree of distortion (in %), and it is interpreted that the aberration correction function is better as the curves approach the Y axis. , In the imaging lens according to the third embodiment of the present invention, since values of images appear adjacent to the Y-axis in almost all fields, spherical aberration, astigmatism, and distortion aberration are all excellent.

4 is a configuration diagram of an imaging lens module according to a fourth embodiment of the present invention.

Referring to FIG. 4, the first lens 10 according to the fourth embodiment of the present invention has a convex shape on the water side, and the second lens 20 to the fourth lens 40 have a convex shape on the image side. In addition, the fifth lens 50 may have a concave water-side shape.

In addition, the first lens 10 has a + power arrangement, the second lens 20 has a + power arrangement, the third lens 30 has a-power arrangement, and the fourth lens 40 ) Has a + power arrangement, and the fifth lens 50 has a + power arrangement.

On the other hand, having the power arrangement of +, +, -, +, + in the order of the first lens 10 to the fifth lens 50 as described above takes into account the optical performance of the imaging lens, manufacturing cost, and miniaturization of the imaging device. This is the optimal power arrangement that has been set.

In addition, the fifth lens 50 is preferably formed in a concave shape in the vicinity of the optical axis and a convex shape toward the periphery in order to secure the curvature of the image surface and telecentricity, and from the center (near the optical axis) The angle of incidence of the light rays across the periphery can be made close to normal to the lens.

Meanwhile, in the imaging lens according to the fourth embodiment, any one, part, or combination or all of Conditional Expressions 1 to 10 according to the first embodiment may be applied.

The imaging lens according to the fourth exemplary embodiment of the present invention illustrated in FIG. 4 having such characteristics may have specific characteristics as shown in Tables 10 to 12 below.

Here, Table 10 shows lens data of each lens surface.

S _x Radius of curvature (R) Thickness or distance (d) Refractive index (N) Abbesu (vd) One 2.4666607 0.4 1.62 60.3 2 3.3486476 0.22455 3 3.7039823 0.724971 1.755 27.5 4 -6.104735 0.250397 5 -4.601062 0.540914 1.536 56.5 6 19.009019 0.679227 7 40.71257 0.791624 1.536 56.5 8 -1.703299 0.718318 9 -1.345482 0.4 1.536 56.5 10 -66.88236 0.2

Table 11 below is a focal length according to the fourth embodiment.

Focal length f 4.7 f ₁ 15.165056 f ₂ 3.810656 f ₃ -4.815865 f ₄ 3.085073 f ₅ 5.4098

Table 12 below shows preferred specific values for each item.

Item value N ₃ /N ₁ 0.948148148 N ₃ /N ₂ 0.875213675 V ₁ /V ₃ 1.067256637 V ₂ /V ₃ 0.486725664 │V ₁ -V ₃ │ 3.8 │V ₂ -V ₃ │ 29 f/f ₁ 0.309923023 f/f ₄ 1.523464761 │R ₁ /R ₂ │ 0.736614016 │R ₇ /R ₈ │ 23.90218647

On the other hand, FIG. 8 is a graph showing an aberration diagram according to the fourth embodiment of the present invention, showing longitudinal spherical aberration, astigmatic field curves, and distortion in order from the left. It is a graph.

In FIG. 8, the Y-axis means the size of the image, the X-axis means the focal length (in mm) and the degree of distortion (in %), and it is interpreted that as the curves approach the Y-axis, the aberration correction function is good. , In the imaging lens according to the third embodiment of the present invention, since values of images appear adjacent to the Y-axis in almost all fields, spherical aberration, astigmatism, and distortion aberration are all excellent.

According to the present invention, a lens material, a lens shape, and power distribution are optimized by the above technical features, and an imaging lens having excellent reliability against temperature changes can be implemented.

From the above description, those skilled in the art will recognize that various changes and modifications can be made without departing from the technical spirit of the present invention, and the technical scope of the present invention is not limited to the contents described in the embodiments, but claims It should be determined according to the scope and the scope equivalent thereto.

10: first lens 20: second lens
30: third lens 40: fourth lens
50: fifth lens 60: filter
70: light receiving element

Claims (20)

From the object side to the top side in order,
A first lens having positive (+) power;
A second lens having positive (+) power;
A third lens having negative power;
A fourth lens having positive (+) power; And
Including a fifth lens having negative (-) power,
The first lens has a meniscus shape in which an object side surface is convex and an image side surface is concave,
The object side surface of the fourth lens is convex in the optical axis,
An image pickup lens having an image-side surface of the fifth lens convex in an optical axis. The method of claim 1,
The first lens and the second lens are an imaging lens formed of a glass material. The method of claim 2,
The first lens is an imaging lens that is a glass mold lens. delete The method of claim 1,
The second lens is an imaging lens having convex surfaces. From the object side to the top side in order,
A first lens having positive (+) power;
A second lens having positive (+) power;
A third lens having negative power;
A fourth lens having positive (+) power; And
Including a fifth lens having negative (-) power,
The first lens has a meniscus shape in which an object side surface is convex and an image side surface is concave,
The third lens is an imaging lens having a concave shape on both sides. From the object side to the top side in order,
A first lens having positive (+) power;
A second lens having positive (+) power;
A third lens having negative power;
A fourth lens having positive (+) power; And
Including a fifth lens having negative (-) power,
The first lens has a meniscus shape in which an object side surface is convex and an image side surface is concave,
The fourth lens is an imaging lens in which both sides are convex in an optical axis. The method of claim 1,
The fifth lens is an imaging lens having a meniscus shape in an optical axis. The method of claim 1,
At least one of the first to fifth lenses has one or both surfaces aspheric. The method of claim 1,
An imaging lens including a diaphragm provided in front of the object side of the first lens. The method of claim 1,
The imaging lens is an imaging lens that satisfies the following Conditional Expression 1.
<Conditional Expression 1>
0.8 <N1/N2 <1
Here, N1 is a refractive index of the first lens, and N2 is a refractive index of the second lens. The method of claim 1,
The imaging lens is an imaging lens that satisfies the following Conditional Expression 2.
<Conditional Expression 2>
0.8 <N3/N2 <1
Here, N2 is a refractive index of the second lens, and N3 is a refractive index of the third lens. The method of claim 1,
The imaging lens is an imaging lens that satisfies the following Conditional Expression 3.
<Conditional Expression 3>
1 <V1/V3 <1.5
Here, V1 is an Abbe number of the first lens, and V3 is an Abbe number of the third lens. The method of claim 1,
The imaging lens is an imaging lens that satisfies the following Conditional Expression 4.
<Conditional Expression 4>
0 <V2/V3 <2
Here, V2 is an Abbe number of the second lens, and V3 is an Abbe number of the third lens. The method of claim 1,
The imaging lens is an imaging lens that satisfies the following Conditional Expression 5.
<Conditional Expression 5>
10 <│V1-V3│< 35
Here, V1 is an Abbe number of the first lens, and V3 is an Abbe number of the third lens. The method of claim 1,
The imaging lens is an imaging lens that satisfies the following Conditional Expression 6.
<Conditional Expression 6>
10 <│V2-V3│< 35
Here, V2 is an Abbe number of the second lens, and V3 is an Abbe number of the third lens. The method of claim 1,
The imaging lens is an imaging lens that satisfies the following Conditional Expression 7.
<Conditional Expression 7>
0.1 <f/f1 <1.5
Here, f is the focal length of the entire optical system, and f1 is the focal length of the first lens. The method of claim 1,
The imaging lens is an imaging lens that satisfies the following Conditional Expression 8.
<Conditional Expression 8>
0.8 <f/f4 <1.7
Here, f denotes a focal length of the entire optical system, and f4 denotes a focal length of the fourth lens. The method of claim 1,
The imaging lens is an imaging lens that satisfies the following Conditional Expression 9.
<Conditional Expression 9>
0 <│R1/R2│< 1
Here, R1 denotes a radius of curvature of the object side surface of the first lens, and R2 denotes a radius of curvature of the image side surface of the first lens. The method of claim 1,
The imaging lens is an imaging lens that satisfies the following Conditional Expression 10.
<Conditional Expression 10>
1 <│R7/R8│ <25
Here, R7 is a radius of curvature of the object side surface of the fourth lens, and R8 is a radius of curvature of the image side surface of the fourth lens.

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