JP2005258467A - Imaging lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging lens for a solid-state imaging device excellent in optical performance and made inexpensive and compact. <P>SOLUTION: The imaging lens which forms an image on the solid-state imaging device and is constituted of three lenses is constituted of a first positive lens (L1), an aperture diaphragm (ST), a second positive lens (L2) having a meniscus shape with a convex surface on an image side, and a third negative lens (L3) having a meniscus shape with a concave surface on the image side in order from an object side. It is constituted to satisfies a conditional formula 0.05<T6/f<0.5, wherein T6 is the axial thickness of the third lens (L3) and f is the focal length of an entire system. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an imaging lens, and more particularly to a small imaging lens suitable for a digital input device (digital still camera, digital video camera, etc.) that captures an image of a subject with a solid-state imaging device.

  In recent years, with the spread of personal computers and the like, digital still cameras, digital video cameras and the like (hereinafter simply referred to as “digital cameras”) that can easily capture image information into digital devices are becoming popular at the individual user level. Such digital cameras are expected to become increasingly popular as image information input devices.

  In addition, miniaturization of solid-state imaging devices such as CCDs (Charge Coupled Devices) mounted on digital cameras has progressed, and accordingly, further miniaturization of digital cameras is required. For this reason, there is a strong demand for a compact imaging lens that occupies the largest volume in a digital input device. Although the easiest way to reduce the size of the imaging lens is to reduce the size of the solid-state imaging device, it is necessary to reduce the size of the light-receiving device, which increases the difficulty of manufacturing the solid-state imaging device. The performance required for the imaging lens is also increased.

  On the other hand, if the size of the imaging lens is reduced while leaving the size of the solid-state imaging device as it is, the exit pupil position will inevitably approach the image plane. When the exit pupil position approaches the image plane, the off-axis light beam emitted from the imaging lens is obliquely incident on the image plane, so that the condensing performance of the microlens provided in front of the solid-state imaging device is sufficient This causes a problem that the brightness of the image changes extremely between the central portion of the image and the peripheral portion of the image. In order to solve this problem, if it is attempted to move the exit pupil position of the imaging lens far away, it is inevitable that the entire imaging lens is enlarged.

In addition, due to the recent competition for lower prices, there is an increasing demand for cost reduction in imaging lenses. In response to the above demand, Patent Documents 1 to 3 propose an imaging lens having a three-lens configuration.
JP 2001-272598 A Japanese Patent Application Laid-Open No. 2002-688889 Japanese Patent Laid-Open No. 11-52227

  The imaging lens having a three-lens configuration disclosed in Patent Document 1 has a total length of about three times the focal length and is not compact. The imaging lens disclosed in Patent Document 2 is compact with a total length of about twice the focal length, but is not low in cost because it uses two glass lenses. The imaging lens disclosed in Patent Document 3 has a total length of about 2.5 times the focal length and is not compact. The angle of view is about 40 degrees, and the angle of view is insufficient for use as an imaging lens.

  The present invention has been made in view of such a situation, and an object thereof is to provide an imaging lens for a solid-state imaging device that has good optical performance, is low-cost, and is compact.

In order to achieve the above object, an imaging lens according to a first aspect of the present invention is an imaging lens having a three-lens configuration for forming an image on a solid-state imaging device. And a positive meniscus second lens having a convex image side and a third lens having a negative meniscus shape having a concave image side, and the following conditional expression (A3) is satisfied.
0.05 <T6 / f <0.5 (A3)
However,
T6: On-axis lens thickness of the third lens,
f: focal length of the entire system,
It is.

The imaging lens of the second invention is characterized in that, in the first invention, the following conditional expression (A2x) is satisfied.
-1.695 ≦ f3 / f1 <-0.15… (A2x)
However,
f3: focal length of the third lens
f1: focal length of the first lens,
It is.

  According to the present invention, it is possible to realize a low-cost and compact imaging lens for a solid-state imaging device having good optical performance. If the imaging lens according to the present invention is used in a digital input device such as a camera mounted on a mobile phone or a digital camera, it can contribute to high performance, high functionality, low cost, and compactness of the device.

  Hereinafter, embodiments of an imaging lens according to the present invention will be described with reference to the drawings. 1 to 12 show the lens configurations of the first to twelfth embodiments in optical cross sections, respectively. Each of the imaging lenses according to each embodiment is a single-focus lens for imaging (for example, for a digital camera) that forms an optical image on a solid-state imaging device (for example, CCD), and is a first lens in order from the object side. (L1), an aperture stop (ST), a second lens (L2), and a third lens (L3). The three lenses (L1 to L3) are all plastic lenses, and the lens surfaces (r1, r2, r4 to r7) are aspherical surfaces. On the image side of the third lens (L3), a parallel plane plate-like glass filter (GF) corresponding to an optical low-pass filter or the like is disposed.

  The optical configurations of the first to fifth embodiments (FIGS. 1 to 5) are, in order from the object side, a first negative or positive first lens (L1) having a weak power (an amount defined by the reciprocal of the focal length). And an aperture stop (ST), a positive second lens (L2), a negative third lens (L3), and a glass filter (GF). Sixth to eighth embodiments ( The optical configuration of FIGS. 6 to 8 is, in order from the object side, a positive first lens (L1), an aperture stop (ST), a positive second lens (L2), and a negative third lens (L3). ) And a glass filter (GF), and the optical configuration of the ninth to twelfth embodiments (FIGS. 9 to 12) includes, in order from the object side, a positive first lens (L1), It consists of an aperture stop (ST), a positive second lens (L2), a positive third lens (L3), and a glass filter (GF). Therefore, the (negative or positive) / positive / negative three-lens configuration employed in the first to eighth embodiments is the lens type A, and is employed in the ninth to twelfth embodiments. The feature of each embodiment will be described below with a lens type B having a configuration of three positive, positive, and positive lenses.

<Lens Type A ... (Negative or Positive) / Positive / Negative>
In the first to third embodiments (FIGS. 1 to 3), the first lens (L1) has a negative meniscus shape with a weak power with the convex surface facing the object side, and the second lens (L2) Has a positive biconvex shape, and the third lens (L3) has a negative meniscus shape with a concave surface facing the image side. In this way, in order from the object side, the first lens (L1) composed of a negative meniscus lens having a weak power, the aperture stop (ST), the second lens (L2) composed of a biconvex positive lens, and the image side. The third lens (L3) consisting of a concave negative meniscus lens and the lens type A with negative, positive, and negative power arrangement balance the optical performance, cost, and compactness of the imaging lens. Is preferable.

  In the fourth and fifth embodiments (FIGS. 4 and 5), the first lens (L1) has a weak positive power, and the second lens (L2) is a positive with the convex surface facing the image side. The third lens (L3) has a negative meniscus shape with a concave surface facing the image side. In this manner, in order from the object side, the first lens (L1) composed of a positive lens with weak power, the aperture stop (ST), the second lens (L2) composed of a positive meniscus lens convex on the image side, and the image Constructing the lens type A with positive, positive, and negative power arrangement with the third lens (L3) consisting of a negative negative meniscus lens on the side balances the optical performance, cost, and compactness of the imaging lens. This is preferable.

  In the sixth to eighth embodiments (FIGS. 6 to 8), the first lens (L1) has positive power, and the second lens (L2) is positive with the convex surface facing the image side. It has a meniscus shape, and the third lens (L3) has a negative meniscus shape with a concave surface facing the image side. Thus, in order from the object side, the first lens (L1) made of a positive lens, the aperture stop (ST), the second lens (L2) made of a positive meniscus lens convex on the image side, and a concave on the image side. In order to balance the optical performance, cost, and compactness of the imaging lens, the lens type A with positive, positive, and negative power distribution is composed of the third lens (L3) consisting of a negative meniscus lens. preferable.

  In the lens type A imaging lens, conditional expressions that should be satisfied will be described below. However, it is not necessary to satisfy all the conditional expressions described below at the same time, and it is possible to achieve the corresponding actions and effects as long as each conditional expression is satisfied independently according to the optical configuration. Needless to say, satisfying a plurality of conditional expressions is more desirable from the viewpoint of optical performance, miniaturization, assembly, and the like.

In the first to fifth embodiments, the first lens (L1) has a weak power, but it is preferable that the power satisfies the following conditional expression (A0).
| F / f1 | <0.6 (A0)
However,
f: focal length of the entire system,
f1: Focal length of the first lens (L1),
It is.

  Conditional expression (A0) prescribes a condition range for reducing performance deterioration mainly due to manufacturing errors with respect to the first lens (L1) having low power. Outside the range of conditional expression (A0), the power of the first lens (L1) becomes too strong. As a result, each aberration generated in the first lens (L1) becomes large, and after the second lens (L2). The burden of aberration correction becomes large, and performance deterioration due to manufacturing errors becomes severe.

Regarding the third lens (L3), it is desirable to satisfy the following conditional expression (A1), and it is more desirable to satisfy the conditional expression (A0).
-2.2 <f / f3 <-0.79… (A1)
However,
f: focal length of the entire system,
f3: focal length of the third lens (L3),
It is.

  Conditional expression (A1) defines a condition range for mainly balancing coma aberration with respect to the third lens (L3). If the lower limit of conditional expression (A1) is exceeded, coma will deteriorate and adverse effects on lateral chromatic aberration will increase. On the contrary, when the upper limit of conditional expression (A1) is exceeded, coma becomes worse and the adverse effect on astigmatism increases.

In the lens type A with positive / positive / negative power arrangement as in the fourth to eighth embodiments, the following conditional expression (A2) may be satisfied with respect to the first and third lenses (L1, L3). In particular, it is desirable to satisfy the following conditional expression (A2a), and it is more desirable to satisfy the conditional expression (A2b).
-2.6 <f3 / f1 <-0.15… (A2)
-1.1 <f3 / f1 <-0.15… (A2a)
-0.35 <f3 / f1 <-0.15… (A2b)
However,
f3: focal length of the third lens (L3),
f1: Focal length of the first lens (L1),
It is.

  Conditional expressions (A2), (A2a), and (A2b) mainly define a condition range for balancing the total length and aberration. Exceeding the upper limit of conditional expression (A2) is advantageous for aberration correction, but causes an increase in the total length. On the contrary, when the lower limit of conditional expression (A2) is exceeded, it is advantageous for shortening the overall length, but the aberration deterioration (particularly, distortion aberration and field curvature deterioration) becomes significant.

Regarding the third lens (L3), it is desirable to satisfy the following conditional expression (A3), and it is more desirable to satisfy the following conditional expression (A3a). It is further desirable to satisfy at least one of the conditional expressions (A0), (A1), (A2), (A2a), and (A2b). In the lens type A in which the power arrangement is positive, positive, and negative as in the fourth to eighth embodiments, the second lens (L2) has a positive meniscus shape that is convex on the image side, and the third lens (L3 ) Has a negative meniscus shape that is concave on the image side, and preferably satisfies the following conditional expression (A3), and more preferably satisfies the following conditional expression (A3a).
0.05 <T6 / f <0.5 (A3)
0.05 <T6 / f <0.4… (A3a)
However,
T6: On-axis lens thickness of the third lens (L3),
f: focal length of the entire system,
It is.

  Conditional expressions (A3) and (A3a) prescribe the condition range for balancing the lateral chromatic aberration and the manufacturability of the lens with respect to the third lens (L3). If the upper limit of conditional expression (A3) is exceeded, it will be difficult to satisfactorily correct lateral chromatic aberration. On the other hand, when the lower limit of conditional expression (A3) is exceeded, the thickness of the lens is too thin, making it difficult to manufacture.

<Lens type B ... Positive / Positive / Positive>
In the ninth to twelfth embodiments (FIGS. 9 to 12), the first lens (L1) has a positive meniscus shape with the convex surface facing the object side, and the second lens (L2) is an image. The third lens (L3) has a positive meniscus shape with a convex surface facing the image side. Thus, in order from the object side, the first lens (L1) composed of a positive meniscus lens convex toward the object side, the aperture stop (ST), and the second lens (L2) composed of a positive lens convex toward the image side. It is preferable to form the lens type B with the third lens (L3) composed of a positive meniscus lens convex on the image side, in order to satisfactorily balance the optical performance, cost, and compactness of the imaging lens.

  In the lens type B imaging lens, conditional expressions that should be satisfied will be described below. However, it is not necessary to satisfy all the conditional expressions described below at the same time, and it is possible to achieve the corresponding actions and effects as long as each conditional expression is satisfied independently according to the optical configuration. Needless to say, satisfying a plurality of conditional expressions is more desirable from the viewpoint of optical performance, miniaturization, assembly, and the like.

Regarding the third lens (L3), it is desirable to satisfy the following conditional expression (B1).
0.2 <f / f3 <0.4 (B1)
However,
f: focal length of the entire system,
f3: focal length of the third lens (L3),
It is.

  Conditional expression (B1) defines a condition range for mainly balancing coma aberration with respect to the third lens (L3). If the lower limit of conditional expression (B1) is exceeded, coma will deteriorate and adverse effects on lateral chromatic aberration will increase. On the contrary, when the upper limit of conditional expression (B1) is exceeded, coma becomes worse and the adverse effect on astigmatism increases.

Regarding the first and third lenses (L1, L3), it is desirable to satisfy the following conditional expression (B2).
0.5 <f3 / f1 <2.6 (B2)
However,
f3: focal length of the third lens (L3),
f1: Focal length of the first lens (L1),
It is.

  Conditional expression (B2) mainly defines a condition range for balancing the total length and aberration. Exceeding the upper limit of conditional expression (B2) is advantageous for aberration correction, but increases the total length. On the contrary, when the lower limit of conditional expression (B2) is exceeded, it is advantageous for shortening the overall length, but the aberration deterioration (particularly, distortion aberration and field curvature deterioration) becomes significant.

For the third lens (L3), it is desirable to satisfy the following conditional expression (B3), the first lens (L1) is composed of a positive meniscus lens convex on the object side, and the second lens (L2) is an image. In a three-lens type B lens configuration including a side convex positive lens and the third lens (L3) including an image side convex positive meniscus lens, it is more desirable to satisfy the following conditional expression (B3).
0.05 <T6 / f <0.4 (B3)
However,
T6: On-axis lens thickness of the third lens (L3),
f: focal length of the entire system,
It is.

  Conditional expression (B3) prescribes a condition range for balancing the lateral chromatic aberration and the manufacturability of the lens mainly with respect to the third lens (L3). If the upper limit of conditional expression (B3) is exceeded, it will be difficult to satisfactorily correct lateral chromatic aberration. On the other hand, when the lower limit of conditional expression (B3) is exceeded, the thickness of the lens is too thin and manufacturing becomes difficult.

<Preferred configuration common to lens types A and B>
As described above, the first to third lenses (L1 to L3) used in the first to twelfth embodiments are all plastic lenses, and each lens surface (r1, r2, r4 to r7) is an aspherical surface. As described above, it is desirable that all the lenses (L1 to L3) are made of plastic lenses, and it is desirable that at least one surface of all the lenses (L1 to L3) is made of an aspherical surface. Constructing all the lenses (L1 to L3) with plastic lenses is effective in reducing the cost of the imaging lens, and using at least one aspheric surface for each lens (L1 to L3). Has a great effect on correction of spherical aberration, coma and distortion.

  The imaging lenses of the first to twelfth embodiments are configured only by a refractive lens that deflects incident light by refraction (that is, a lens that deflects at the interface between media having different refractive indexes). However, it is not limited to this. For example, a diffractive lens that deflects incident light by diffraction, a refractive / diffractive hybrid lens that deflects incident light by a combination of diffraction and refraction, and a refractive index distribution type that deflects incident light according to the refractive index distribution in the medium A lens or the like may be used. However, since the refractive index distribution type lens whose refractive index changes in the medium increases the cost due to its complicated manufacturing method, the imaging lens according to the present invention uses homogeneous material lenses as the first to third lenses (L1 to L3). It is desirable to use

  In the first to twelfth embodiments, in addition to the aperture stop (ST), a light flux restricting plate for cutting unnecessary light may be disposed as necessary, such as prisms (for example, right angle prisms), mirrors By placing a surface (for example, a reflecting surface, a refracting surface, a diffracting surface) that does not have optical power (a quantity defined by the reciprocal of the focal length) in the optical path using a class (for example, a plane mirror) The optical path may be bent before, after, or in the middle of the imaging lens. The bending position can be set as necessary, and by appropriately bending the optical path, it is possible to achieve an apparently thin and compact digital input device (such as a digital camera) equipped with an imaging lens. is there.

  The imaging lenses according to the first to twelfth embodiments are suitable for use as a small imaging lens for digital input equipment. By combining this with an optical low-pass filter or a solid-state imaging device, an image of a subject is optically generated. Therefore, it is possible to configure an imaging lens device that takes in and outputs as an electrical signal. The imaging lens apparatus is a camera used for still image shooting and moving image shooting of a subject {eg, digital camera; video camera; digital video unit, personal computer, mobile computer, pen-type scanner, mobile phone, personal digital assistant (PDA: Personal Digital Assistant), the main components of these peripheral devices (mouse, scanner, printer, other digital input / output devices) etc. built-in or external camera}, for example, in order from the object (subject) side An imaging lens that forms an optical image of the above, an optical filter such as an optical low-pass filter and an infrared cut filter, and a solid-state imaging device that converts the optical image formed by the imaging lens into an electrical signal .

Accordingly, the above-described first to twelfth embodiments include inventions (i) to (vi) having the following configurations, and the configurations provide good optical performance and are low cost and compact. An imaging lens device can be realized. If this is applied to a digital camera or the like, it can contribute to high performance, high functionality, low cost and compactness of the camera.
(i) An imaging lens device comprising an imaging lens that forms an optical image and a solid-state imaging device that converts an optical image formed by the imaging lens into an electrical signal, wherein the imaging lens is an object In order from the side, the first lens having positive or negative power, the second lens having positive power, and the third lens having negative power are composed of three lenses, and the conditional expression (A0) , (A1), (A2), (A2a), (A2b), (A3), and (A3a).
(ii) An imaging lens device comprising: an imaging lens that forms an optical image; and a solid-state imaging device that converts an optical image formed by the imaging lens into an electrical signal, wherein the imaging lens is an object In order from the side, the first lens having positive power, the second lens having positive power, and the third lens having positive power are composed of three lenses, and the conditional expressions (B1), ( An imaging lens device satisfying at least one of B2) and (B3).
(iii) The imaging lens device according to (i) or (ii), further comprising an aperture stop between the first lens and the second lens.
(iv) The imaging lens device according to any one of (i) to (iii), wherein the first to third lenses are made of plastic lenses.
(v) The imaging lens device according to any one of (i) to (iv), wherein each of the first to third lenses has at least one aspheric surface.
(vi) The imaging lens device according to any one of (i) to (v), wherein the first to third lenses are formed of a homogeneous material lens.

  As the solid-state imaging device, for example, a CCD or CMOS (Complementary Metal Oxide Semiconductor) sensor composed of a plurality of pixels is used, and an optical image formed by the imaging lens is converted into an electrical signal by the solid-state imaging device. An optical image to be formed by the imaging lens is generated when it is converted into an electrical signal by passing through an optical low-pass filter having a predetermined cutoff frequency characteristic determined by the pixel pitch of the solid-state imaging device. The spatial frequency characteristics are adjusted so that so-called aliasing noise is minimized. The signal generated by the solid-state image sensor is subjected to predetermined digital image processing, image compression processing, etc. as necessary, and is recorded as a digital video signal in a memory (semiconductor memory, optical disk, etc.). Or is converted into an infrared signal and transmitted to another device.

  Note that the optical low-pass filter disposed between the final surface of the imaging lens and the solid-state imaging device is composed of a glass filter (GF) in the first to twelfth embodiments, but is used as a digital filter. Any device according to the input device may be used. For example, a birefringent low-pass filter made of quartz or the like with a predetermined crystal axis direction adjusted, or a phase-type low-pass filter that achieves the required optical cutoff frequency characteristics by the diffraction effect can be applied. is there.

<< Lens type with three or more lenses in order of positive, positive, negative from the object side >>
Next, other embodiments of positive / positive / negative imaging lenses will be described with reference to the drawings. FIGS. 25 to 27 show the lens configurations of the thirteenth to fifteenth embodiments in optical cross sections, respectively. The imaging lenses of the thirteenth to fifteenth embodiments are all single-focus lenses for imaging (for example, for digital cameras) that form an optical image on a solid-state imaging device (for example, CCD). Then, in order from the object side, a positive first lens (L1), an aperture stop (ST), a positive second lens (L2), and a negative third lens (L3) with a concave surface facing the image surface side A parallel plane plate-like glass filter (GF) corresponding to an optical low-pass filter or the like is disposed on the image plane side. In the thirteenth to fifteenth embodiments, all lens surfaces (r1, r2, r4 to r7) are aspherical surfaces.

  The lens configurations of the thirteenth to fifteenth embodiments will be described in more detail. In the thirteenth embodiment, the first lens (L1) is a plastic lens having a positive meniscus shape with the convex surface facing the image surface side, and the second lens (L2) is a positive lens with the convex surface facing the image surface side. The third lens (L3) is a plastic lens having a negative meniscus shape with a concave surface facing the image plane side. In the fourteenth embodiment, the first lens (L1) is a glass lens having a positive meniscus shape with a convex surface facing the object side, and the second lens (L2) is a positive lens with a convex surface facing the image surface side. It is a plastic lens having a meniscus shape, and the third lens (L3) is a negative plastic lens having a biconcave shape. In the fifteenth embodiment, the first lens (L1) is a glass lens having a positive meniscus shape with a convex surface facing the object side, and the second lens (L2) is a positive lens with a convex surface facing the image surface side. The third lens (L3) is a plastic lens having a negative meniscus shape with a concave surface facing the image plane.

  As in the thirteenth to fifteenth embodiments, in the lens type with positive / positive / negative power arrangement, one of the first and second lenses (L1, L2) is a glass lens, and the other is plastic. The lens, and the third lens (L3) is a plastic lens with the concave surface facing the image plane, so that the exit pupil position, optical performance, cost, compactness, and manufacturability required for an imaging lens for a solid-state imaging device It becomes possible to balance well.

  Next, embodiments of positive / positive / negative / negative imaging lenses will be described with reference to the drawings. FIGS. 31 to 34 show the lens configurations of the sixteenth to nineteenth embodiments in optical cross sections, respectively. The imaging lenses of the sixteenth to nineteenth embodiments are all single-focus lenses for imaging (for example, for digital cameras) that form an optical image on a solid-state imaging device (for example, CCD). Then, in order from the object side, it consists of a positive front group (GrF), an aperture stop (ST), and a negative or positive rear group (GrR), and the image side corresponds to an optical low-pass filter etc. A parallel plane plate-like glass filter (GF) is disposed. The front group (GrF) is composed of a first lens (L1) made up of a positive lens, and the rear group (GrR) is made up of a second lens (L2) made up of a positive lens and a negative lens in order from the object side. The third lens (L3) composed of a lens and the fourth lens (L4) composed of a negative lens are used. In other words, the imaging lenses according to the sixteenth to nineteenth embodiments have, in order from the object side, a positive first lens (L1), an aperture stop (ST), a positive second lens (L2), and a negative first lens. It has a four-lens configuration with three lenses (L3) and a negative fourth lens (L4). In each lens configuration diagram (FIGS. 31 to 34), the surface with ri (i = 1, 2, 3,...) Is the i-th surface counted from the object side, and ri * The marked surface is an aspherical surface.

  The lens configurations of the sixteenth to nineteenth embodiments will be described in more detail. In the sixteenth to eighteenth embodiments, the first lens (L1) is a positive glass lens having a meniscus shape with a convex surface facing the object side, and the second lens (L2) has a convex surface facing the image side. It is a positive plastic lens having a meniscus shape, the third lens (L3) is a negative plastic lens having a meniscus shape with a convex surface facing the image side, and the fourth lens (L4) is a negative negative lens having a biconcave shape. It is a plastic lens. The front group (GrF) has a positive power, and the rear group (GrR) has a negative power. In the nineteenth embodiment, the first lens (L1) is a positive glass lens having a biconvex shape, and the second lens (L2) is a positive plastic lens having a meniscus shape having a convex surface facing the image side. The third lens (L3) is a negative plastic lens having a meniscus shape with a convex surface facing the image side, and the fourth lens (L4) is a negative plastic lens having a biconcave shape. The front group (GrF) and the rear group (GrR) both have positive power.

  As in the sixteenth to nineteenth embodiments, in order from the object side, a positive lens convex to the object side, an aperture stop (ST), a positive meniscus lens convex to the image side, and a negative negative convex to the image side. By adopting a four-lens configuration consisting of a meniscus lens and a negative lens having at least an aspheric image side surface and a concave lens on the image side, the lens system can be made compact while realizing high optical performance and an appropriate exit pupil position. Cost reduction can be achieved. Further, as in the sixteenth to nineteenth embodiments, the glass lens and the plastic lens are appropriately arranged, that is, only the first lens (L1) is constituted by the glass lens, and the other lenses (L2 to L4). By using all plastic lenses, it is possible to realize a low-cost and compact imaging lens with good optical performance. Further, by constituting only the first lens (L1) with a glass lens, the performance deterioration with respect to the temperature change is reduced, and the optical performance is improved over a wide temperature range.

  As described above, an imaging lens for a solid-state imaging device is required to have high performance, downsizing, and low cost. However, if the exit pupil position is moved away, the entire imaging lens is increased in size. I will. Furthermore, due to the recent competition for lower prices, there is an increasing demand for lowering costs for imaging lenses, and the higher density of solid-state imaging devices in recent years has resulted in higher performance required for imaging lenses. It is coming. In response to the above demands, imaging lenses for solid-state imaging devices aiming for downsizing have been proposed in Japanese Patent Application Laid-Open Nos. 2000-180719 and 2002-228922.

  However, the imaging lens described in Japanese Patent Laid-Open No. 2000-180719 has an angle of view of 50 degrees or less, and the angle of view is insufficient for use as an imaging lens. On the other hand, the imaging lens described in Japanese Patent Application Laid-Open No. 2002-228922 has a field angle of 60 degrees or more, and can be said to be a sufficient field angle to be used as an imaging lens. However, since the position of the aperture stop is located in front of the lens system, the manufacturing error with respect to the peripheral performance tends to be severe. Therefore, it is difficult to maintain the peripheral performance. In addition, the imaging lenses described in JP 2000-180719 A and JP 2002-228922 A are arranged in the order of a positive lens and a negative lens in order from the object side. In such a configuration where the negative lens is positioned in front of the lens system, it is difficult to make the lens compact.

  The above-mentioned problems are caused by the lens types of three or more lenses having lenses in the order of positive / positive / negative from the object side, for example, fourth to eighth embodiments (three positive / positive / negative lenses), Eliminating the configuration of the thirteenth to fifteenth embodiments (three positive, positive and negative lenses) and the sixteenth to nineteenth embodiments (four positive, positive, negative and negative lenses) Is possible. In other words, it is possible to position the exit pupil farther by optimizing the final lens surface shape, while making the lens compact by properly arranging the lenses, and with good optical performance, low cost and compact solid-state imaging An imaging lens for an element can be provided. The characteristic configuration will be described in detail below.

  The fourth to eighth and thirteenth to nineteenth embodiments are imaging lenses that form an image on a solid-state imaging device, and in order from the object side are two positive lenses {first and second lenses (L1 , L2). } And at least one negative lens {corresponding to the third lens (L3) and the fourth lens (L4). }, And the lens surface closest to the image side is an aspherical surface with the concave surface facing the image side, and the aspherical surface has a point of inflection. The aspherical shape of the lens surface closest to the image side is a concave surface in the vicinity of the optical axis (AX) as can be seen from the cross-sectional shape of the lens surface shown in the lens configuration diagram. It has a shape. A point that changes from the concave surface to the convex surface is an inflection point.

  As described above, by making the lens surface shape near the optical axis (AX) concave on the image side, it is possible to reduce the total lens length. If the entire lens surface is concave, the exit pupil position at the periphery will be close, but by making the lens surface shape from the middle band to the outermost periphery convex, the exit pupil position can be located further away. It becomes possible. The convex shape from the middle band to the outermost periphery is constituted by an aspherical surface with the concave surface facing the image side having an inflection point. By using an aspherical surface having such a characteristic shape for the lens surface closest to the image side, it is possible to realize an imaging lens having a far exit pupil position even though the total lens length is small. By adopting a lens arrangement that continues from positive, positive, and negative from the object side, the total lens length can be further effectively reduced.

  The optimum aperture stop position in the above case is between the first lens (L1) and the second lens (L2). That is, as in the fourth to eighth and thirteenth to nineteenth embodiments, the positive lens {corresponds to the first lens (L1) in order from the object side. }, An aperture stop (ST), and a lens group consisting of at least one lens {corresponding to second and third lenses (L2, L3) and second to fourth lenses (L2 to L4, GrR). The negative lens {corresponding to the third lens (L3) or the fourth lens (L4) in which the lens closest to the image side of the lens group has a concave surface facing the image side. It is desirable that the lens surface on the image side of the negative lens is an aspheric surface, and the aspheric surface has an inflection point. In the front stop type having an aperture stop on the object side of the first lens, the change in the height of the light beam passing through each lens is very large, which increases the sensitivity to manufacturing errors, resulting in manufacturing. Performance degradation due to errors will increase. On the other hand, the rear aperture type having an aperture stop on the image side of the most image side lens (that is, the final lens) is not suitable for an imaging lens for a solid-state imaging device because the exit pupil position is extremely close. The optimum aperture stop position for balancing the manufacturing error and the exit pupil position is between the first lens (L1) and the second lens (L2).

Further, in order from the object side, it corresponds to a positive lens {first lens (L1). }, An aperture stop (ST), and a lens group consisting of at least one lens {corresponding to second and third lenses (L2, L3) and second to fourth lenses (L2 to L4, GrR). }, And the lens surface closest to the image side of the lens group is an aspherical surface with the concave surface facing the image side. The aspherical surface has an inflection point and satisfies the following conditional expression (1) It is desirable.
1.1 <f / Y '<1.9 (1)
However,
f: focal length of the entire system,
Y ': Maximum image height,
It is.

  Conditional expression (1) defines a condition range for balancing the total lens length and the front lens diameter. If the lower limit of conditional expression (1) is exceeded, the diameter of the front lens will increase, leading to an increase in the radial direction of the imaging lens device, and it will be difficult to correct distortion. On the contrary, if the upper limit of conditional expression (1) is exceeded, the total length of the optical system increases, leading to an increase in the size of the imaging lens device in the optical axis (AX) direction.

It is desirable to satisfy the following conditional expression (1a), and it is more desirable to satisfy conditional expression (1b). Conditional expressions (1a) and (1b) define a more preferable condition range from the above viewpoint and the like among the condition ranges defined by the conditional expression (1).
1.3 <f / Y '<1.8 (1a)
1.4 <f / Y '<1.7… (1b)

  As in the fourth to eighth and thirteenth to nineteenth embodiments, it is desirable that at least one surface of all the lenses is aspheric. Providing at least one aspheric surface for each of the first to third lenses (L1 to L3) or the first to fourth lenses (L1 to L4) has a great effect on correction of spherical aberration, coma aberration, and distortion. is there. The imaging lenses according to the fourth to eighth and thirteenth to nineteenth embodiments are refracting lenses that deflect incident light by refraction (that is, deflection is performed at the interface between media having different refractive indexes). Type lens), but usable lenses are not limited to this. For example, a diffractive lens that deflects incident light by diffracting action, a refractive / diffractive hybrid lens that deflects incident light by combining diffractive action and refracting action, and a refractive index distribution that deflects incident light by a refractive index distribution in the medium A mold lens or the like may be used. However, since the refractive index distribution type lens in which the refractive index changes in the medium increases the cost due to its complicated manufacturing method, it is desirable that all the lenses used be a homogeneous material lens.

  In addition to the stop (ST), a light beam restricting plate for cutting unnecessary light may be arranged as necessary, and prisms (for example, right-angle prisms), mirrors (for example, plane mirrors), etc. are disposed in the optical path. The optical path may be bent before, after, or in the middle of the imaging lens on a surface having no optical power (for example, a reflective surface, a refractive surface, or a diffractive surface) {for example, an optical axis (AX ) May be bent about 90 degrees to reflect the light flux. }. The bending position can be set as necessary, and by appropriately bending the optical path, it is possible to achieve an apparently thin and compact digital input device (such as a digital camera) equipped with an imaging lens. is there.

  The imaging lenses of the fourth to eighth and thirteenth to nineteenth embodiments are suitable for use as a compact imaging lens for digital input equipment, and are combined with an optical low-pass filter or a solid-state imaging device. An imaging lens device that optically captures a subject image and outputs it as an electrical signal can be configured. The imaging lens device is a camera used for still image shooting or moving image shooting of a subject (for example, a digital camera; a video camera; a digital video unit, a personal computer, a mobile computer, a mobile phone, a personal digital assistant (PDA), These are the main components of the peripheral devices (mouse, scanner, printer, other digital input / output devices) etc. built-in or external camera}. For example, the optical image of the object in order from the object (subject) side. An imaging lens to be formed, an optical filter such as an optical low-pass filter and an infrared cut filter, and a solid-state imaging device that converts an optical image formed by the imaging lens into an electrical signal.

Accordingly, the above-described fourth to eighth and thirteenth to nineteenth embodiments include inventions (I) to (V) having the following configurations, and the configurations have good optical performance. In addition, a compact imaging lens device can be realized at low cost. If this is applied to a digital camera or the like, it can contribute to high performance, high functionality, low cost and compactness of the camera.
(I) An imaging lens device comprising an imaging lens that forms an optical image and an imaging element that converts an optical image formed by the imaging lens into an electrical signal, wherein the imaging lens is on the object side In order, there are two positive lenses and at least one negative lens, the lens surface closest to the image side is an aspherical surface with the concave surface facing the image side, and the aspherical surface has an inflection point. An imaging lens device characterized by the above.
(II) An imaging lens device comprising: an imaging lens that forms an optical image; and an imaging device that converts the optical image formed by the imaging lens into an electrical signal, wherein the imaging lens is on the object side In order from a positive lens, an aperture stop, and a lens group composed of at least one lens. The lens closest to the image side of the lens group is a negative lens with a concave surface facing the image side. An imaging lens device, wherein a lens surface on an image side of a lens is an aspheric surface, and the aspheric surface has an inflection point.
(III) An imaging lens device comprising: an imaging lens that forms an optical image; and an imaging device that converts an optical image formed by the imaging lens into an electrical signal, wherein the imaging lens is on the object side In order from a positive lens, an aperture stop, and a lens group including at least one lens, and the lens surface closest to the image side of the lens group is an aspherical surface with a concave surface facing the image side, An imaging lens device, wherein an aspherical surface has an inflection point and satisfies at least one of the conditional expressions (1), (1a), and (1b).
(IV) The imaging lens device according to any one of (I) to (III) above, wherein all the lenses each have at least one aspheric surface.
(V) The imaging lens device according to any one of (I) to (IV) above, wherein all lenses are composed of homogeneous material lenses.

  As the imaging device, for example, a solid-state imaging device such as a CCD or CMOS (Complementary Metal Oxide Semiconductor) sensor composed of a plurality of pixels is used, and an optical image formed by the imaging lens is converted into an electrical signal by the solid-state imaging device. The An optical image to be formed by the imaging lens is generated when it is converted into an electrical signal by passing through an optical low-pass filter having a predetermined cutoff frequency characteristic determined by the pixel pitch of the solid-state imaging device. The spatial frequency characteristics are adjusted so that so-called aliasing noise is minimized. The signal generated by the solid-state image sensor is subjected to predetermined digital image processing, image compression processing, etc. as necessary, and is recorded as a digital video signal in a memory (semiconductor memory, optical disk, etc.). Or is converted into an infrared signal and transmitted to another device. Note that the optical low-pass filter disposed between the final surface of the imaging lens and the solid-state imaging device is composed of a glass filter (GF) in each embodiment, but depends on the digital input device used. Anything is acceptable. For example, a birefringent low-pass filter made of quartz or the like with a predetermined crystal axis direction adjusted, or a phase-type low-pass filter that achieves the required optical cutoff frequency characteristics by the diffraction effect can be applied. is there.

  Hereinafter, the imaging lens embodying the present invention will be described more specifically with reference to construction data and the like. Examples 1 to 19 listed here correspond to the first to nineteenth embodiments, respectively, and are lens configuration diagrams showing the first to nineteenth embodiments (FIGS. 1 to 12, FIG. 12). 25 to 27 and FIGS. 31 to 34) show the lens configurations of the corresponding Examples 1 to 19, respectively. In the construction data of each example, ri (i = 1, 2, 3, ...) is the radius of curvature (mm) of the i-th surface counted from the object side, di (i = 1, 2, 3,. ..) indicates the i-th axis upper surface distance (mm) counted from the object side, and Ni (i = 1,2,3, ...), νi (i = 1,2,3, ...). .) Shows the refractive index (Nd) and Abbe number (νd) of the i-th optical element counted from the object side with respect to the d-line. The focal length (f, mm) and F number (FNO) of the entire system are shown together with other data, and the corresponding values of the conditional expressions are shown in Tables 1 and 2.

The surface marked with * in the radius of curvature ri indicates that the surface is an aspherical refractive optical surface or a surface having a refractive action equivalent to that of the aspherical surface. It shall be defined in The aspheric data of each example is shown together with other data.
X (H) = (C0 · H ² ) / {1 + √ (1-ε · C0 ² · H ² )} + Σ (Ai · H ⁱ )… (AS)
However, in the formula (AS)
X (H): Displacement in the direction of the optical axis (AX) at the position of height H (based on the surface vertex),
H: height in the direction perpendicular to the optical axis (AX),
C0: Paraxial curvature (= 1 / curvature radius),
ε: quadric surface parameter,
Ai: i-th order aspheric coefficient (data when Ai = 0 is omitted),
It is.

  FIGS. 13 to 24, FIGS. 28 to 30, and FIGS. 35 to 38 are aberration diagrams corresponding to Examples 1 to 19, and FIGS. 13 to 24, FIGS. 28 to 30, and FIGS. 38, (A) is a spherical aberration diagram, (B) is an astigmatism diagram, and (C) is a distortion diagram {FNO: F number, Y ′: maximum image height (mm)}. In the spherical aberration diagram, the solid line (d) represents the d line, the alternate long and short dash line (g) represents the g line, the alternate long and two short dashes line (c) represents the amount of spherical aberration (mm) with respect to the c line, and the broken line (SC) represents the sine. The amount of unsatisfied conditions (mm). In the astigmatism diagram, the broken line (DM) represents the astigmatism (mm) for the d-line on the meridional surface, and the solid line (DS) represents the astigmatism (mm) for the d-line on the sagittal surface. Yes. In the distortion diagram, the solid line represents the distortion (%) with respect to the d-line.

Example 1
f = 3.469, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 2.800
d1 = 1.322 N1 = 1.58340 ν1 = 30.23 (L1)
r2 * = 1.595
d2 = 0.741
r3 = ∞ (ST)
d3 = 0.442
r4 * = 5.686
d4 = 1.686 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.141
d5 = 0.100
r6 * = 18.824
d6 = 1.026 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 2.039
d7 = 1.000
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.32631, A4 = 0.23941 × 10 ^-1 , A6 = -0.24142 × 10 ^-3 , A8 = 0.87227 × 10 ^-3
[Aspherical data of 2nd surface (r2)]
ε = 0.20000 × 10, A4 = 0.83403 × 10 ^-1 , A6 = 0.98460 × 10 ^-3 , A8 = 0.49924 × 10 ^-1
[Aspherical data of 4th surface (r4)]
ε = 0.18973 × 10, A4 = −0.11614 × 10 ⁻¹ , A6 = −0.22756 × 10 ⁻¹ , A8 = 0.82323 × 10 ⁻²
[Aspherical data of 5th surface (r5)]
ε = 0.26870, A4 = 0.34068 × 10 ^-1 , A6 = -0.14733 × 10 ^-1 , A8 = 0.56763 × 10 ^-3
[Aspherical data of 6th surface (r6)]
ε = 0.0 A4 = -0.47058 × 10 ^-1 , A6 = -0.90811 × 10 ^-2 , A8 = 0.19180 × 10 ^-2
[Aspherical data of 7th surface (r7)]
ε = 0.35130, A4 = -0.86078 × 10 ^-1 , A6 = 0.14913 × 10 ^-1 , A8 = -0.18277 × 10 ^-2

Example 2
f = 3.467, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 3.914
d1 = 1.633 N1 = 1.58340 ν1 = 30.23 (L1)
r2 * = 2.253
d2 = 0.545
r3 = ∞ (ST)
d3 = 0.300
r4 * = 5.484
d4 = 2.097 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -0.992
d5 = 0.100
r6 * = 6.928
d6 = 0.700 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 1.261
d7 = 1.000
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.10000 × 10, A4 = 0.15050 × 10 ⁻¹ , A6 = 0.17624 × 10 ⁻² , A8 = -0.28942 × 10 ^-3 , A10 = 0.15435 × 10 ^-3
[Aspherical data of 2nd surface (r2)]
ε = 0.10000 × 10, A4 = 0.12063, A6 = 0.53318 × 10 ⁻¹ , A8 = -0.34519 × 10 ⁻¹ , A10 = 0.15360
[Aspherical data of 4th surface (r4)]
ε = 0.10000 × 10, A4 = 0.21812 × 10 ⁻¹ , A6 = 0.13669 × 10 ⁻¹ , A8 = 0.89058 × 10 ⁻² , A13 = -0.10085 × 10 ⁻¹
[Aspherical data of 5th surface (r5)]
ε = 0.10969, A4 = 0.13179, A6 = -0.87983 × 10 ^-1 , A8 = 0.39597 × 10 ^-1 , A10 = -0.51378 × 10 ^-2
[Aspherical data of 6th surface (r6)]
ε = 0.10000 × 10, A4 = -0.98804 × 10 ^-1 , A6 = 0.25381 × 10 ^-1 , A8 = -0.41254 × 10 ^-2 , A10 = -0.74291 × 10 ^-3
[Aspherical data of 7th surface (r7)]
ε = -0.50000 × 10, A4 = -0.69548 × 10 ^-1 , A6 = 0.27279 × 10 ^-1 , A8 = -0.76305 × 10 ^-2 , A10 = 0.73965 × 10 ^-3

Example 3
f = 3.965, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 5.638
d1 = 1.569 N1 = 1.58340 ν1 = 30.23 (L1)
r2 * = 3.303
d2 = 0.394
r3 = ∞ (ST)
d3 = 0.200
r4 * = 4.256
d4 = 2.649 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.065
d5 = 0.100
r6 * = 19.154
d6 = 0.799 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 1.266
d7 = 1.000
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.10000 × 10, A4 = 0.12129 × 10 ^-1 , A6 = 0.31044 × 10 ^-2 , A8 = -0.11652 × 10 ^-2 , A10 = 0.19214 × 10 ^-3
[Aspherical data of 2nd surface (r2)]
ε = 0.10000 × 10, A4 = 0.10276, A6 = 0.19545 × 10 ^-1 , A8 = -0.73712 × 10 ^-2 , A10 = 0.55142 × 10 ^-1
[Aspherical data of 4th surface (r4)]
ε = 0.10000 × 10, A4 = 0.45950 × 10 ^-1 , A6 = 0.47759 × 10 ^-2 , A8 = 0.79466 × 10 ^-2 , A10 = -0.12984 × 10 ^-1
[Aspherical data of 5th surface (r5)]
ε = 0.11091, A4 = 0.12806, A6 = -0.70237 × 10 ^-1 , A8 = 0.26286 × 10 ^-1 , A10 = -0.27364 × 10 ^-2
[Aspherical data of 6th surface (r6)]
ε = 0.10000 × 10, A4 = −0.85336 × 10 ⁻¹ , A6 = 0.25832 × 10 ⁻¹ , A8 = −0.89579 × 10 ⁻² , A10 = 0.67422 × 10 ⁻³
[Aspherical data of 7th surface (r7)]
ε = -0.50000 × 10, A4 = -0.52773 × 10 ⁻¹ , A6 = 0.17861 × 10 ⁻¹ , A8 = −0.46675 × 10 ⁻² , A10 = 0.43220 × 10 ^-3

Example 4
f = 3.507, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 68.391
d1 = 0.872 N1 = 1.53048 ν1 = 55.72 (L1)
r2 * = -6.304
d2 = 0.938
r3 = ∞ (ST)
d3 = 0.500
r4 * = -3.703
d4 = 1.649 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -0.852
d5 = 0.100
r6 * = 11.946
d6 = 0.700 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 1.225
d7 = 1.000
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.51000 × 10 ² , A4 = 0.56767 × 10 ^-2 , A6 = 0.35339 × 10 ^-2 , A8 = -0.16790 × 10 ^-2 , A10 = 0.18541 × 10 ^-3
[Aspherical data of 2nd surface (r2)]
ε = 0.15652 × 10 ² , A4 = 0.29585 × 10 ⁻¹ , A6 = 0.49258 × 10 ⁻² , A8 = −0.68370 × 10 ⁻² , A10 = 0.21683 × 10 ⁻²
[Aspherical data of 4th surface (r4)]
ε = 0.14877 × 10, A4 = -0.79140 × 10 ^-1 , A6 = -0.47628 × 10 ^-1 , A8 = 0.48397 × 10 ^-1 , A10 = -0.11082
[Aspherical data of 5th surface (r5)]
ε = -0.10000 × 10, A4 = -0.10074 × 10 ^-1 , A6 = -0.10146, A8 = 0.69391 × 10 ^-1 , A10 = -0.22979 × 10 ^-1
[Aspherical data of 6th surface (r6)]
ε = 0.21028 × 10, A4 = −0.38111 × 10 ⁻¹ , A6 = 0.40875 × 10 ⁻² , A8 = 0.27790 × 10 ⁻² , A10 = −0.24091 × 10 ⁻²
[Aspherical data of 7th surface (r7)]
ε = -0.60000 × 10, A4 = -0.45478 × 10 ^-1 , A6 = 0.20696 × 10 ^-1 , A8 = -0.67145 × 10 ^-2 , A10 = 0.63538 × 10 ^-3

Example 5
f = 4.046, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 5.219
d1 = 1.013 N1 = 1.53048 ν1 = 55.72 (L1)
r2 * = -64.896
d2 = 0.748
r3 = ∞ (ST)
d3 = 0.500
r4 * = -4.392
d4 = 1.756 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -0.904
d5 = 0.100
r6 * = 20.088
d6 = 0.725 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 1.208
d7 = 1.000
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = -0.70781 × 10, A4 = 0.89349 × 10 ^-2 , A6 = 0.47221 × 10 ^-2 , A8 = -0.10936 × 10 ^-2 , A10 = 0.26309 × 10 ^-3
[Aspherical data of 2nd surface (r2)]
ε = -0.14000 × 10 ² , A4 = 0.21091 × 10 ^-1 , A6 = 0.65881 × 10 ^-2 , A8 = -0.31253 × 10 ^-2 , A10 = 0.14822 × 10 ^-2
[Aspherical data of 4th surface (r4)]
ε = 0.21386 × 10, A4 = −0.36204 × 10 ⁻¹ , A6 = −0.25647 × 10 ⁻¹ , A8 = 0.63204 × 10 ⁻¹ , A10 = −0.70302 × 10 ⁻¹
[Aspherical data of 5th surface (r5)]
ε = -0.97822, A4 = 0.29364 × 10 ^-1 , A6 = -0.10042, A8 = 0.61685 × 10 ^-1 , A10 = -0.15831 × 10 ^-1
[Aspherical data of 6th surface (r6)]
ε = -0.20000 × 10, A4 = -0.46735 × 10 ^-1 , A6 = 0.63444 × 10 ^-2 , A8 = 0.57281 × 10 ^-2 , A10 = -0.26912 × 10 ^-2
[Aspherical data of 7th surface (r7)]
ε = -0.60000 × 10, A4 = -0.60010 × 10 ^-1 , A6 = 0.24137 × 10 ^-1 , A8 = -0.56437 × 10 ^-2 , A10 = 0.43112 × 10 ^-3

Example 6
f = 4.057, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 3.887
d1 = 1.137 N1 = 1.53048 ν1 = 55.72 (L1)
r2 * = 50.974
d2 = 0.745
r3 = ∞ (ST)
d3 = 0.500
r4 * = -3.040
d4 = 1.696 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.374
d5 = 0.100
r6 * = 1.971
d6 = 0.700 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 1.157
d7 = 1.000
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = -0.17782 × 10, A4 = 0.61057 × 10 -2, A6 = 0.14542 × 10 -2, A8 = -0.49868 × 10 -3, A10 = 0.16539 × 10 -3
[Aspherical data of 2nd surface (r2)]
ε = 0.16000 × 10 ² , A4 = 0.61220 × 10 ^-2 , A6 = -0.75168 × 10 ^-3 , A8 = 0.15948 × 10 ^-2 , A10 = -0.17231 × 10 ^-4
[Aspherical data of 4th surface (r4)]
ε = 0.84433, A4 = 0.61538 × 10 ^-2 , A6 = -0.21453, A8 = 0.30585, A10 = -0.20991
[Aspherical data of 5th surface (r5)]
ε = 0.36507, A4 = -0.44642 × 10 ^-1 , A6 = 0.12082 × 10 ^-1 , A8 = 0.88202 × 10 ^-2 , A10 = -0.56296 × 10 ^-2
[Aspherical data of 6th surface (r6)]
ε = -0.20000 × 10, A4 = -0.14745, A6 = 0.32555 × 10 ^-1 , A8 = 0.43398 × 10 ^-2 , A10 = -0.22720 × 10 ^-2
[Aspherical data of 7th surface (r7)]
ε = -0.19045 × 10, A4 = -0.97978 × 10 ^-1 , A6 = 0.23732 × 10 ^-1 , A8 = -0.25696 × 10 ^-2 , A10 = -0.40956 × 10 ^-5

Example 7
f = 5.413, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 3.262
d1 = 1.267 N1 = 1.53048 ν1 = 55.72 (L1)
r2 * = 20.506
d2 = 0.605
r3 = ∞ (ST)
d3 = 1.011
r4 * = -2.627
d4 = 1.329 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.750
d5 = 0.100
r6 * = 6.747
d6 = 1.769 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 2.711
d7 = 0.500
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.23583, A4 = 0.42634 × 10 ^-2 , A6 = 0.70946 × 10 ^-3 , A8 = 0.83522 × 10 ^-4 , A10 = 0.22563 × 10 ^-4
[Aspherical data of 2nd surface (r2)]
ε = 0.13080 × 10 ² , A4 = 0.76363 × 10 ^-2 , A6 = -0.96051 × 10 ^-3 , A8 = 0.12099 × 10 ^-2 , A10 = -0.32280 × 10 ^-3
[Aspherical data of 4th surface (r4)]
ε = 0.14778 × 10, A4 = 0.46580 × 10 ^-2 , A6 = -0.48590 × 10 ^-1 , A8 = 0.29449 × 10 ^-1 , A10 = -0.35940 × 10 ^-2
[Aspherical data of 5th surface (r5)]
ε = 0.54871, A4 = -0.31360 × 10 ^-1 , A6 = 0.95481 × 10 ^-2 , A8 = -0.21117 × 10 ^-2 , A10 = 0.74248 × 10 ^-3
[Aspherical data of 6th surface (r6)]
ε = 0.35876 × 10 ^-1 , A4 = -0.60741 × 10 ^-1 , A6 = 0.13571 × 10 ^-1 , A8 = -0.98325 × 10 ^-3 , A10 = -0.49719 × 10 ^-4
[Aspherical data of 7th surface (r7)]
ε = -0.54011 × 10, A4 = -0.17861 × 10 ^-1 , A6 = 0.16540 × 10 ^-3 , A8 = 0.11796 × 10 ^-3 , A10 = -0.10468 × 10 ^-4

Example 8
f = 5.414, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 2.566
d1 = 1.227 N1 = 1.53048 ν1 = 55.72 (L1)
r2 * = 18.606
d2 = 0.369
r3 = ∞ (ST)
d3 = 0.935
r4 * = -1.834
d4 = 1.208 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.611
d5 = 0.100
r6 * = 7.215
d6 = 1.581 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 2.841
d7 = 0.500
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.16794, A4 = 0.43888 × 10 ^-2 , A6 = 0.28598 × 10 ^-3 , A8 = 0.32325 × 10 ^-3 , A10 = -0.24401 × 10 ^-3
[Aspherical data of 2nd surface (r2)]
ε = -0.73024 × 10, A4 = -0.29787 × 10 ^-2 , A6 = -0.20862 × 10 ^-2 , A8 = -0.10682 × 10 ^-2 , A10 = 0.34571 × 10 ^-3
[Aspherical data of 4th surface (r4)]
ε = 0.12492 × 10, A4 = 0.29931 × 10 ^-2 , A6 = -0.49256 × 10 ^-1 , A8 = 0.23979 × 10 ^-1 , A10 = 0.79079 × 10 ^-3
[Aspherical data of 5th surface (r5)]
ε = 0.53675, A4 = -0.23290 × 10 ^-1 , A6 = 0.52301 × 10 ^-2 , A8 = 0.10769 × 10 ^-2 , A10 = 0.44801 × 10 ^-3
[Aspherical data of 6th surface (r6)]
ε = 0.20000 × 10, A4 = -0.66312 × 10 ^-1 , A6 = 0.15524 × 10 ^-1 , A8 = -0.15169 × 10 ^-2 , A10 = -0.38654 × 10 ^-4
[Aspherical data of 7th surface (r7)]
ε = -0.60000 × 10, A4 = -0.25548 × 10 ^-1 , A6 = 0.14515 × 10 ^-2 , A8 = -0.25702 × 10 ^-4 , A10 = -0.80 128 × 10 ^-5

Example 9
f = 3.470, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 1.928
d1 = 1.028 N1 = 1.53048 ν1 = 55.72 (L1)
r2 * = 2.310
d2 = 0.478
r3 = ∞ (ST)
d3 = 0.300
r4 * = 8.421
d4 = 1.304 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.151
d5 = 0.655
r6 * = -0.468
d6 = 0.720 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = -0.694
d7 = 0.300
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.10000 × 10, A4 = -0.45870 × 10 ^-2 , A6 = 0.29663 × 10 ^-2 , A8 = -0.12412 × 10 ^-2 , A10 = -0.94981 × 10 ^-3
[Aspherical data of 2nd surface (r2)]
ε = 0.10000 × 10, A4 = -0.11631 × 10 ^-1 , A6 = 0.15359, A8 = -0.35362, A10 = 0.22705
[Aspherical data of 4th surface (r4)]
ε = 0.10000 × 10, A4 = -0.12407, A6 = 0.87272 × 10 ^-1 , A8 = -0.30646, A10 = 0.23712
[Aspherical data of 5th surface (r5)]
ε = 0.10000 × 10, A4 = 0.27864 × 10 ⁻¹ , A6 = 0.64946 × 10 ⁻¹ , A8 = -0.13857, A10 = 0.11579
[Aspherical data of 6th surface (r6)]
ε = 0.13801, A4 = 0.36196, A6 = 0.16987, A8 = -0.10315, A10 = 0.81031 × 10 ^-1
[Aspherical data of 7th surface (r7)]
ε = 0.17413, A4 = 0.15173, A6 = 0.72208 × 10 ⁻¹ , A8 = -0.28908 × 10 ⁻¹ , A10 = 0.74165 × 10 ⁻²

Example 10
f = 3.469, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 2.173
d1 = 1.103 N1 = 1.53048 ν1 = 55.72 (L1)
r2 * = 2.584
d2 = 0.602
r3 = ∞ (ST)
d3 = 0.328
r4 * = 6.726
d4 = 1.283 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.160
d5 = 0.736
r6 * = -0.459
d6 = 0.738 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = -0.680
d7 = 0.300
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.10000 × 10, A4 = 0.87958 × 10 ^-3 , A6 = 0.42137 × 10 ^-2 , A8 = -0.16799 × 10 ^-3 , A10 = -0.19193 × 10 ^-3
[Aspherical data of 2nd surface (r2)]
ε = 0.10000 × 10, A4 = 0.93253 × 10 ^-2 , A6 = 0.15533, A8 = -0.24491, A10 = 0.13194
[Aspherical data of 4th surface (r4)]
ε = 0.10000 × 10, A4 = -0.98391 × 10 ^-1 , A6 = 0.94609 × 10 ^-1 , A8 = -0.17520, A10 = 0.12094
[Aspherical data of 5th surface (r5)]
ε = 0.10000 × 10, A4 = 0.44653 × 10 ⁻¹ , A6 = 0.55013 × 10 ⁻¹ , A8 = -0.12054, A10 = 0.11213
[Aspherical data of 6th surface (r6)]
ε = 0.13153, A4 = 0.36562, A6 = 0.16321, A8 = -0.11039, A10 = 0.86597 × 10 ^-1
[Aspherical data of 7th surface (r7)]
ε = 0.16282, A4 = 0.15658, A6 = 0.66062 × 10 ⁻¹ , A8 = −0.28592 × 10 ⁻¹ , A10 = 0.75366 × 10 ⁻²

Example 11
f = 2.357, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 3.284
d1 = 0.988 N1 = 1.53048 ν1 = 55.72 (L1)
r2 * = 8.603
d2 = 0.249
r3 = ∞ (ST)
d3 = 0.231
r4 * = 2.351
d4 = 1.000 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -0.806
d5 = 0.367
r6 * = -0.328
d6 = 0.700 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = -0.557
d7 = 0.200
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.10000 × 10, A4 = -0.82390 × 10 ^-1 , A6 = -0.51231 × 10 ^-3 , A8 = -0.31114 × 10 ^-1 , A10 = 0.20505 × 10 ^-1
[Aspherical data of 2nd surface (r2)]
ε = 0.10000 × 10, A4 = -0.22908, A6 = 0.19307, A8 = -0.66911, A10 = 0.11352 × 10
[Aspherical data of 4th surface (r4)]
ε = 0.10000 × 10, A4 = -0.31044, A6 = -0.13877, A8 = 0.59855, A10 = -0.34008 × 10
[Aspherical data of 5th surface (r5)]
ε = 0.10000 × 10, A4 = 0.19846, A6 = 0.34588, A8 = -0.10718 × 10, A10 = 0.22259 × 10
[Aspherical data of 6th surface (r6)]
ε = 0.14294, A4 = 0.16786 × 10, A6 = 0.77941, A8 = -0.21235 × 10, A10 = 0.29745 × 10
[Aspherical data of 7th surface (r7)]
ε = 0.22025, A4 = 0.51811, A6 = 0.40947, A8 = -0.41631, A10 = 0.19224

Example 12
f = 3.909, FNO = 2.8
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 1.946
d1 = 1.063 N1 = 1.53048 ν1 = 55.72 (L1)
r2 * = 2.908
d2 = 0.461
r3 = ∞ (ST)
d3 = 0.369
r4 * = 25.898
d4 = 1.214 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.222
d5 = 0.719
r6 * = -0.512
d6 = 0.864 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = -0.791
d7 = 0.300
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.10000 × 10, A4 = -0.71083 × 10 ^-2 , A6 = 0.83355 × 10 ^-2 , A8 = -0.43965 × 10 ^-2 , A10 = 0.15236 × 10 ^-2
[Aspherical data of 2nd surface (r2)]
ε = 0.10000 × 10, A4 = 0.48178 × 10 ^-2 , A6 = 0.77795 × 10 ^-1 , A8 = -0.11808, A10 = 0.82135 × 10 ^-1
[Aspherical data of 4th surface (r4)]
ε = 0.10000 × 10, A4 = -0.67192 × 10 ^-1 , A6 = 0.75859 × 10 ^-2 , A8 = -0.45131 × 10 ^-1 , A10 = -0.15867 × 10 ^-2
[Aspherical data of 5th surface (r5)]
ε = 0.10000 × 10, A4 = 0.57645 × 10 ^-1 , A6 = 0.64121 × 10 ^-2 , A8 = -0.12843 × 10 ^-1 , A10 = 0.27561 × 10 ^-1
[Aspherical data of 6th surface (r6)]
ε = 0.15149, A4 = 0.34428, A6 = 0.14586, A8 = -0.13119, A10 = 0.71148 × 10 ^-1
[Aspherical data of 7th surface (r7)]
ε = 0.19214, A4 = 0.13217, A6 = 0.45573 × 10 ⁻¹ , A8 = −0.23420 × 10 ⁻¹ , A10 = 0.52064 × 10 ⁻²

Example 13
f = 3.382, FNO = 2.80
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = -10.748
d1 = 0.756 N1 = 1.53048 ν1 = 55.72 (L1)
r2 * = -6.165
d2 = 0.933
r3 = ∞ (ST)
d3 = 0.500
r4 * = -12.672
d4 = 1.734 N2 = 1.48749 ν2 = 70.44 (L2)
r5 * = -0.898
d5 = 0.100
r6 * = 5.623
d6 = 0.700 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 1.145
d7 = 1.300
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = -0.49000 × 10 ² , A4 = 0.19628 × 10 ^-1 , A6 = 0.42261 × 10 ^-2 , A8 = -0.14046 × 10 ^-2 , A10 = 0.24571 × 10 ^-3
[Aspherical data of 2nd surface (r2)]
ε = -0.61499 × 10, A4 = 0.46300 × 10 ^-1 , A6 = 0.58156 × 10 ^-2 , A8 = -0.55287 × 10 ^-2 , A10 = 0.25143 × 10 ^-2
[Aspherical data of 4th surface (r4)]
ε = -0.10000 × 10, A4 = -0.36178 × 10 ^-1 , A6 = -0.35359 × 10 ^-1 , A8 = 0.33661 × 10 ^-1 , A10 = -0.76906 × 10 ^-1
[Aspherical data of 5th surface (r5)]
ε = -0.10000 × 10, A4 = 0.88131 × 10 ^-2 , A6 = -0.10394, A8 = 0.66365 × 10 ^-1 , A10 = -0.21004 × 10 ^-1
[Aspherical data of 6th surface (r6)]
ε = -0.19193 × 10, A4 = -0.51842 × 10 ^-1 , A6 = 0.75512 × 10 ^-3 , A8 = 0.23514 × 10 ^-2 , A10 = -0.21619 × 10 ^-2
[Aspherical data of 7th surface (r7)]
ε = -0.45157 × 10, A4 = -0.44404 × 10 ^-1 , A6 = 0.19663 × 10 ^-1 , A8 = -0.73281 × 10 ^-2 , A10 = 0.92529 × 10 ^-3

Example 14
f = 5.403, FNO = 2.80
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 3.427
d1 = 1.256 N1 = 1.58913 ν1 = 61.28 (L1)
r2 * = 13.824
d2 = 0.643
r3 = ∞ (ST)
d3 = 0.972
r4 * = -3.551
d4 = 1.640 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.328
d5 = 0.100
r6 * = -31.222
d6 = 1.584 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 2.125
d7 = 0.800
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.45664, A4 = 0.50687 × 10 ^-2 , A6 = 0.84990 × 10 ^-3 , A8 = -0.13419 × 10 ^-4 , A10 = 0.45261 × 10 ^-4
[Aspherical data of 2nd surface (r2)]
ε = 0.13638 × 10 ² , A4 = 0.12538 × 10 ^-1 , A6 = -0.40314 × 10 ^-2 , A8 = 0.29052 × 10 ^-2 , A10 = -0.63264 × 10 ^-3
[Aspherical data of 4th surface (r4)]
ε = 0.20000 × 10, A4 = −0.17811 × 10 ⁻¹ , A6 = −0.44803 × 10 ⁻¹ , A8 = 0.25403 × 10 ⁻¹ , A10 = −0.27515 × 10 ⁻²
[Aspherical data of 5th surface (r5)]
ε = 0.28496, A4 = -0.90398 × 10 ^-3 , A6 = 0.58812 × 10 ^-2 , A8 = -0.40268 × 10 ^-2 , A10 = 0.10098 × 10 ^-2
[Aspherical data of 6th surface (r6)]
ε = 0.0, A4 = -0.60414 × 10 ^-1 , A6 = 0.15910 × 10 ^-1 , A8 = -0.10850 × 10 ^-2 , A10 = -0.90198 × 10 ^-4
[Aspherical data of 7th surface (r7)]
ε = -0.52095 × 10, A4 = -0.30068 × 10 ^-1 , A6 = 0.30856 × 10 ^-2 , A8 = -0.17047 × 10 ^-3 , A10 = 0.10885 × 10 ^-6

Example 15
f = 4.212, FNO = 4.00
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 1.823
d1 = 1.195 N1 = 1.48749 ν1 = 70.44 (L1)
r2 * = 17.003
d2 = 0.300
r3 = ∞ (ST)
d3 = 0.575
r4 * = -1.231
d4 = 1.371 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -0.881
d5 = 0.100
r6 * = 4.980
d6 = 0.749 N3 = 1.58340 ν3 = 30.23 (L3)
r7 * = 1.193
d7 = 0.500
r8 = ∞
d8 = 0.500 N4 = 1.51680 ν4 = 64.20 (GF)
r9 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.41144, A4 = 0.85264 × 10 ^-2 , A6 = 0.61779 × 10 ^-2 , A8 = -0.18563 × 10 ^-2 , A10 = -0.12302 × 10 ^-2
[Aspherical data of 2nd surface (r2)]
ε = 0.16000 × 10 ² , A4 = −0.94292 × 10 ⁻² , A6 = −0.339468 × 10 ⁻¹ , A8 = 0.43553 × 10 ⁻¹ , A10 = −0.19370 × 10 ⁻¹
[Aspherical data of 4th surface (r4)]
ε = 0.19571 × 10, A4 = -0.22360 × 10 ^-1 , A6 = -0.23890, A8 = 0.29336, A10 = 0.36819
[Aspherical data of 5th surface (r5)]
ε = 0.66179 × 10 ^-1 , A4 = 0.59525 × 10 ^-1 , A6 = -0.70445 × 10 ^-1 , A8 = 0.15571 × 10 ^-1 , A10 = 0.54156 × 10 ^-2
[Aspherical data of 6th surface (r6)]
ε = 0.12482 × 10, A4 = -0.14933, A6 = 0.56598 × 10 ^-1 , A8 = -0.76101 × 10 ^-2 , A10 = -0.24802 × 10 ^-4
[Aspherical data of 7th surface (r7)]
ε = -0.60000 × 10, A4 = -0.74292 × 10 ^-1 , A6 = 0.64193 × 10 ^-2 , A8 = 0.15186 × 10 ^-2 , A10 = -0.29432 × 10 ^-3

Example 16
f = 7.277, FNO = 4.00
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 3.548
d1 = 1.161 N1 = 1.58913 ν1 = 61.28 (L1)
r2 * = 16.802
d2 = 0.593
r3 = ∞ (ST)
d3 = 1.343
r4 * = -3.817
d4 = 1.377 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.576
d5 = 0.447
r6 * = -2.730
d6 = 1.686 N3 = 1.58340 ν3 = 30.23 (L3)
r7 = -4.280
d7 = 0.100
r8 = -5.779
d8 = 0.833 N4 = 1.53048 ν4 = 55.72 (L4)
r9 * = 5.219
d9 = 0.500
r10 = ∞
d10 = 0.700 N5 = 1.51680 ν5 = 64.20 (GF)
r11 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.77503, A4 = 0.25359 × 10 ^-2 , A6 = 0.42096 × 10 ^-3 , A8 = 0.12178 × 10 ^-4 , A10 = 0.88312 × 10 ^-5
[Aspherical data of 2nd surface (r2)]
ε = 0.16000 × 10 ² , A4 = 0.60134 × 10 ^-2 , A6 = -0.12266 × 10 ^-2 , A8 = 0.58101 × 10 ^-3 , A10 = -0.11992 × 10 ^-3
[Aspherical data of 4th surface (r4)]
ε = 0.20000 × 10, A4 = -0.23442 × 10 ^-1 , A6 = -0.78672 × 10 ^-2 , A8 = 0.75751 × 10 ^-2 , A10 = -0.35641 × 10 ^-3
[Aspherical data of 5th surface (r5)]
ε = 0.26692, A4 = -0.38537 × 10 ^-2 , A6 = 0.64572 × 10 ^-3 , A8 = -0.20007 × 10 ^-3 , A10 = 0.48166 × 10 ^-3
[Aspherical data of 6th surface (r6)]
ε = 0.19644 × 10 ^-1 , A4 = -0.20508 × 10 ^-1 , A6 = 0.58512 × 10 ^-2 , A8 = -0.43953 × 10 ^-4 , A10 = -0.11200 × 10 ^-3
[Aspherical data of 9th surface (r9)]
ε = -0.24561 × 10, A4 = -0.14117 × 10 ^-1 , A6 = 0.65211 × 10 ^-3 , A8 = -0.11832 × 10 ^-4 , A10 = -0.56001 × 10 ^-6

Example 17
f = 7.224, FNO = 4.00
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 3.085
d1 = 1.254 N1 = 1.48749 ν1 = 70.44 (L1)
r2 * = 132.361
d2 = 0.519
r3 = ∞ (ST)
d3 = 1.333
r4 * = -2.840
d4 = 1.370 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.406
d5 = 0.215
r6 * = -2.977
d6 = 1.421 N3 = 1.58340 ν3 = 30.23 (L3)
r7 = -4.231
d7 = 0.200
r8 * = -3.893
d8 = 0.929 N4 = 1.53048 ν4 = 55.72 (L4)
r9 * = 4.977
d9 = 0.500
r10 = ∞
d10 = 0.700 N5 = 1.51680 ν5 = 64.20 (GF)
r11 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.53903, A4 = 0.16932 × 10 ^-2 , A6 = -0.11741 × 10 ^-3 , A8 = 0.57949 × 10 ^-4 , A10 = -0.71896 × 10 ^-4
[Aspherical data of 2nd surface (r2)]
ε = -0.14000 × 10 ² , A4 = 0.27334 × 10 ^-2 , A6 = -0.26419 × 10 ^-2 , A8 = -0.75325 × 10 ^-4 , A10 = 0.73080 × 10 ^-4
[Aspherical data of 4th surface (r4)]
ε = 0.20000 × 10, A4 = -0.31677 × 10 ^-1 , A6 = -0.75942 × 10 ^-2 , A8 = 0.91685 × 10 ^-2 , A10 = 0.41558 × 10 ^-3
[Aspherical data of 5th surface (r5)]
ε = 0.24552, A4 = -0.52179 × 10 ^-2 , A6 = 0.25889 × 10 ^-2 , A8 = 0.68847 × 10 ^-4 , A10 = 0.47898 × 10 ^-3
[Aspherical data of 6th surface (r6)]
ε = 0.40102 × 10 ^-1 , A4 = -0.18898 × 10 ^-1 , A6 = 0.54964 × 10 ^-2 , A8 = 0.32997 × 10 ^-3 , A10 = -0.26481 × 10 ^-3
[Aspherical data of 8th surface (r8)]
ε = 0.10000 × 10, A4 = 0.48378 × 10 ^-3 , A6 = 0.60634 × 10 ^-3 , A8 = 0.19793 × 10 ^-4 , A10 = -0.16558 × 10 ^-5
[Aspherical data of 9th surface (r9)]
ε = -0.60000 × 10, A4 = -0.16306 × 10 ^-1 , A6 = 0.98 140 × 10 ^-3 , A8 = -0.41108 × 10 ^-4 , A10 = 0.65479 × 10 ^-6

Example 18
f = 7.223, FNO = 3.20
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 3.658
d1 = 1.456 N1 = 1.48749 ν1 = 70.44 (L1)
r2 * = 73.204
d2 = 0.709
r3 = ∞ (ST)
d3 = 1.347
r4 * = -3.303
d4 = 1.559 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.519
d5 = 0.100
r6 * = -5.135
d6 = 1.559 N3 = 1.58340 ν3 = 30.23 (L3)
r7 = -8.750
d7 = 0.200
r8 * = -7.043
d8 = 1.264 N4 = 1.53048 ν4 = 55.72 (L4)
r9 * = 3.768
d9 = 0.500
r10 = ∞
d10 = 0.700 N5 = 1.51680 ν5 = 64.20 (GF)
r11 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.71501, A4 = 0.28518 × 10 ^-2 , A6 = -0.17675 × 10 ^-3 , A8 = 0.14775 × 10 ^-3 , A10 = -0.18376 × 10 ^-4
[Aspherical data of 2nd surface (r2)]
ε = 0.16000 × 10 ² , A4 = 0.63737 × 10 ^-2 , A6 = -0.12019 × 10 ^-2 , A8 = 0.11025 × 10 ^-3 , A10 = -0.14631 × 10 ^-4
[Aspherical data of 4th surface (r4)]
ε = 0.17392 × 10, A4 = -0.19887 × 10 ^-1 , A6 = -0.18654 × 10 ^-1 , A8 = 0.10823 × 10 ^-1 , A10 = -0.98268 × 10 ^-3
[Aspherical data of 5th surface (r5)]
ε = 0.25841, A4 = -0.41793 × 10 ^-3 , A6 = -0.20223 × 10 ^-3 , A8 = -0.33463 × 10 ^-3 , A10 = 0.23695 × 10 ^-3
[Aspherical data of 6th surface (r6)]
ε = 0.00000, A4 = -0.14443 × 10 ^-1 , A6 = 0.39292 × 10 ^-2 , A8 = -0.46118 × 10 ^-4 , A10 = -0.77163 × 10 ^-4
[Aspherical data of 8th surface (r8)]
ε = 0.10000 × 10, A4 = 0.39723 × 10 ^-3 , A6 = 0.28397 × 10 ^-3 , A8 = 0.18192 × 10 ^-5 , A10 = -0.45178 × 10 ^-6
[Aspherical data of 9th surface (r9)]
ε = -0.55782 × 10, A4 = -0.11687 × 10 ^-1 , A6 = 0.76776 × 10 ^-3 , A8 = -0.49279 × 10 ^-4 , A10 = 0.13179 × 10 ^-5

Example 19
f = 5.457, FNO = 3.20
[Curve radius] [Axis spacing] [Refractive index] [Abbe number]
r1 * = 3.253
d1 = 1.288 N1 = 1.48749 ν1 = 70.44 (L1)
r2 * = -86.056
d2 = 0.579
r3 = ∞ (ST)
d3 = 1.036
r4 * = -2.672
d4 = 1.199 N2 = 1.53048 ν2 = 55.72 (L2)
r5 * = -1.179
d5 = 0.100
r6 * = -4.423
d6 = 1.022 N3 = 1.58340 ν3 = 30.23 (L3)
r7 = -7.099
d7 = 0.200
r8 * = -6.526
d8 = 0.956 N4 = 1.53048 ν4 = 55.72 (L4)
r9 * = 2.573
d9 = 0.500
r10 = ∞
d10 = 0.500 N5 = 1.51680 ν5 = 64.20 (GF)
r11 = ∞

[Aspherical data of the first surface (r1)]
ε = 0.61954, A4 = 0.60178 × 10 ^-2 , A6 = -0.12105 × 10 ^-2 , A8 = 0.86233 × 10 ^-3 , A10 = -0.15712 × 10 ^-3
[Aspherical data of 2nd surface (r2)]
ε = -0.14000 × 10 ² , A4 = 0.15001 × 10 ^-1 , A6 = -0.53033 × 10 ^-2 , A8 = 0.12331 × 10 ^-2 , A10 = -0.29962 × 10 ^-3
[Aspherical data of 4th surface (r4)]
ε = 0.11867 × 10, A4 = -0.37808 × 10 ^-1 , A6 = -0.76004 × 10 ^-1 , A8 = 0.79954 × 10 ^-1 , A10 = -0.14867 × 10 ^-1
[Aspherical data of 5th surface (r5)]
ε = 0.25855, A4 = 0.51279 × 10 ^-3 , A6 = -0.23878 × 10 ^-2 , A8 = -0.21119 × 10 ^-2 , A10 = 0.31651 × 10 ^-2
[Aspherical data of 6th surface (r6)]
ε = 0.69924, A4 = -0.37699 × 10 ^-1 , A6 = 0.16425 × 10 ^-1 , A8 = -0.53665 × 10 ^-3 , A10 = -0.77077 × 10 ^-3
[Aspherical data of 8th surface (r8)]
ε = 0.10000 × 10, A4 = 0.22716 × 10 ⁻³ , A6 = 0.10393 × 10 ⁻² , A8 = 0.34646 × 10 ⁻⁵ , A10 = −0.42799 × 10 ⁻⁵
[Aspherical data of 9th surface (r9)]
ε = -0.56964 × 10, A4 = -0.26810 × 10 ^-1 , A6 = 0.32076 × 10 ^-2 , A8 = -0.37062 × 10 ^-3 , A10 = 0.17192 × 10 ^-4

The lens block diagram of 1st Embodiment (Example 1). The lens block diagram of 2nd Embodiment (Example 2). The lens block diagram of 3rd Embodiment (Example 3). The lens block diagram of 4th Embodiment (Example 4). The lens block diagram of 5th Embodiment (Example 5). The lens block diagram of 6th Embodiment (Example 6). The lens block diagram of 7th Embodiment (Example 7). The lens block diagram of 8th Embodiment (Example 8). The lens block diagram of 9th Embodiment (Example 9). The lens block diagram of 10th Embodiment (Example 10). The lens block diagram of 11th Embodiment (Example 11). The lens block diagram of 12th Embodiment (Example 12). FIG. 6 is an aberration diagram of Example 1. FIG. 6 is an aberration diagram of Example 2. FIG. 6 is an aberration diagram of Example 3. FIG. 6 is an aberration diagram of Example 4. FIG. 6 is an aberration diagram of Example 5. FIG. 10 is an aberration diagram of Example 6. FIG. 10 is an aberration diagram of Example 7. FIG. 10 is an aberration diagram of Example 8. FIG. 10 is an aberration diagram of Example 9. FIG. 10 is an aberration diagram of Example 10. FIG. 10 shows aberration diagrams of Example 11. FIG. 10 is an aberration diagram of Example 12. The lens block diagram of 13th Embodiment (Example 13). The lens block diagram of 14th Embodiment (Example 14). The lens block diagram of 15th Embodiment (Example 15). Aberration diagram of Example 13. Aberration diagram of Example 14. FIG. 18 shows aberration diagrams of Example 15. The lens block diagram of 16th Embodiment (Example 16). The lens block diagram of 17th Embodiment (Example 17). The lens block diagram of 18th Embodiment (Example 18). The lens block diagram of 19th Embodiment (Example 19). Aberration diagram of Example 16. Aberration diagram of Example 17. Aberration diagrams of Example 18. Aberration diagrams of Example 19.

Explanation of symbols

L1 first lens
ST Aperture stop
L2 second lens
L3 3rd lens
GF glass filter
AX optical axis

Claims (2)

An imaging lens having a three-lens configuration for forming an image on a solid-state imaging device, in order from the object side, a positive first lens, an aperture stop, a positive meniscus second lens convex on the image side, and an image An imaging lens comprising a third lens having a negative negative meniscus shape and satisfying the following conditional expression (A3):
0.05 <T6 / f <0.5 (A3)
However,
T6: On-axis lens thickness of the third lens,
f: focal length of the entire system,
It is. The imaging lens according to claim 1, wherein the following conditional expression (A2x) is satisfied:
-1.695 ≦ f3 / f1 <-0.15… (A2x)
However,
f3: focal length of the third lens
f1: focal length of the first lens,
It is.

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