TWI774306B - Lens assembly - Google Patents

Abstract

A lens assembly includes a first lens group, a second lens group, a third lens group, and a fourth lens group, all of which are arranged in order from a first side to a second side along an axis. The first lens group is with positive refractive power. The second lens group is with positive refractive power. The third lens group is with positive refractive power. The fourth lens group is with negative refractive power. Light from an object passes through the first lens group, the second lens group, the third lens group, and the fourth lens group in order from a first side along an axis to a second side. The lens assembly further includes a reflective element disposed between the first side and the second side along the axis, wherein the reflective element includes a reflective surface. The intervals between the lens groups can be changed to change an effective focal length of the lens assembly.

Description

Imaging Lens(59)

The present invention relates to an imaging lens.

Optical zoom lenses with traditional architectures have a long overall length, and as the zoom ratio increases, the overall length of the lens increases. Today’s thin and light camera devices such as smartphones, tablets, and mobile devices cannot be equipped with optical zoom lenses with traditional architectures. . Therefore, another imaging lens with a new architecture is required to meet the requirements of miniaturization, high resolution and optical zoom function at the same time, in order to meet the demand for optical zoom function of smart phones.

In view of this, the main purpose of the present invention is to provide an imaging lens, which has a shorter overall lens length, a thinner lens thickness, a higher resolution, and an optical zoom function, but still has good optical performance.

The imaging lens of the present invention includes a first lens group, a second lens group, a third lens group and a fourth lens group. The first lens group has positive refractive power. The second lens group has positive refractive power. The third lens group has positive refractive power. The fourth lens group has negative refractive power. Light from an object sequentially passes through the first lens group, the second lens group, the third lens group and the fourth lens group from a first side to a second side along an axis. The imaging lens further includes a reflection element, the reflection element includes a reflection surface, and the reflection element is disposed between the first side and the second side along the axis. this The distance between the equal lens groups can be changed to allow the imaging lens to change the focal length.

The first lens group includes a 1-1 lens, the 1-1 lens is a meniscus lens with positive refractive power, and includes a convex surface facing the first side along the axis and a concave surface facing the second side along the axis. The lens group includes a 2-1 lens and a 2-2 lens, the 2-1 lens is a meniscus lens with positive refractive power, and includes a convex surface facing the first side along the axis and a concave surface facing the second side along the axis , this 2-2 lens is a meniscus lens with negative refractive power, and includes a convex surface facing the first side along the axis and a concave surface facing the second side along the axis, the 2-1 lens and the 2-2 lens along the axis The axes are arranged in sequence from the first side to the second side, the third lens group includes a 3-1 lens and a 3-2 lens, the 3-1 lens is a meniscus lens with negative refractive power, and includes a concave surface along the The axis faces the first side and a convex surface faces the second side along the axis. The 3-2 lens is a biconvex lens with positive refractive power, and includes a convex surface facing the first side along the axis and another convex surface facing the second side along the axis. , the 3-1 lens and the 3-2 lens are arranged in sequence from the first side to the second side along the axis, and the fourth lens group includes a 4-1 lens, a 4-2 lens and a 4-3 lens, The 4-1 lens is a meniscus lens with positive refractive power, and includes a concave surface facing the first side along the axis and a convex surface facing the second side along the axis, the 4-2 lens is a meniscus lens with refractive power, and Including a concave surface facing the first side along the axis and a convex surface facing the second side along the axis, the 4-3 lens has negative refractive power, and includes a concave surface facing the second side along the axis, this 4-1 lens, this 4-3 lens The -2 lens and this 4-3 lens are sequentially arranged along the axis from the first side to the second side.

The 4-2 lens has negative refractive power, and the 4-3 lens may further include a convex surface facing the first side along the axis. The 4-2 lens has positive refractive power, and the 4-3 lens may further include a concave surface facing the first side along the axis. The 2-1 lens and the 2-2 lens are cemented. The reflective element is disposed between the first side and the first lens group along the axis, and the second lens group and the third lens group may be along the axis Move to bring the imaging lens into focus. The reflective element can act on an axis or a vertical direction of the axis to achieve optical anti-shake. The second lens group moves to the first side along the axis, the third lens group moves to the second side along the axis, and the first lens group and the fourth lens group are fixed, so that the imaging lens can be zoomed from a wide-angle end to a telephoto lens end.

The imaging lens meets at least one of the following conditions: 0.1<(DG12W-DG12T)/(fT-fW)<1; 0.1<(DG23T-DG23W)/(fT-fW)<1; 0.1<(DG34W-DG34T)/ (fT-fW)<1; wherein, DG12W is the distance along the axis when the first lens group and the second lens group are at the wide-angle end, and DG12T is the distance along the axis when the first lens group and the second lens group are at the telephoto end A distance, DG23W is the distance along the axis when the second lens group and the third lens group are at the wide-angle end, DG23T is the distance along the axis when the second lens group and the third lens group are at the telephoto end, DG34W is The distance between the third lens group and the fourth lens group along the axis at the wide-angle end, DG34T is the distance along the axis when the third lens group and the fourth lens group are at the telephoto end, fW is the imaging lens at the wide-angle end is an effective focal length, and fT is an effective focal length of the imaging lens at the telephoto end.

The imaging lens meets at least one of the following conditions: 0.1<DG12W/TTL<0.5; 0.1<DG34W/TTL<0.5; 0<DG23W/Dmax<1; 0.3<Dp/Dmax<2; 3.8<TTL/Dmax<5.2; Among them, DG12W is the distance along the axis of the first lens group and the second lens group at the wide-angle end, DG23W is the distance along the axis of the second lens group and the third lens group at the wide-angle end, and DG34W is the third lens group. A distance along the axis of the lens group and the fourth lens group at the wide-angle end, TTL is the distance on the axis from the first side of the lens closest to the first side to an imaging surface, Dmax is the distance between all the lenses of the imaging lens One of the largest optically effective diameters, Dp is one of the optically effective diameters of the reflective surface.

In order to make the above objects, features, and advantages of the present invention more clearly understood, preferred embodiments are hereinafter described in detail with the accompanying drawings.

1, 2, 3: Imaging lens

P1, P2, P3: Reflective elements

ST1, ST2, ST3: Aperture

LG11, LG21, LG31: The first lens group

LG12, LG22, LG32: Second lens group

LG13, LG23, LG33: The third lens group

LG14, LG24, LG34: Fourth lens group

OF1, OF2, OF3: Filters

L11, L21, L31 1-1: Lens

L12, L22, L32 2-1: Lens

L13, L23, L33 2-2: Lens

L14, L24, L34 3-1: Lens

L15, L25, L35 3-2: Lens

L16, L26, L36 4-1: Lens

L17, L27, L37 4-2: Lens

L18, L28, L38 4-3: Lens

IMA1, IMA2, IMA3: Imaging plane

AX1, AX2, AX3: axis

S11, S21, S31: Incident surface

S12, S22, S32: Reflective surface

S13, S23, S33: Exit surface

S14, S24, S34: Aperture surface

S15, S25, S35 1-1: The first side of the lens

S16, S26, S36 1-1: The second side of the lens

S17, S27, S37 2-1: The first side of the lens

S18, S28, S38 2-1: The second side of the lens

S19, S29, S39 2-2: The first side of the lens

S110, S210, S310 2-2: the second side of the lens

S111, S211, S311 3-1: The first side of the lens

S112, S212, S312 3-1: The second side of the lens

S113, S213, S313 3-2: The first side of the lens

S114, S214, S314 3-2: The second side of the lens

S115, S215, S315 4-1: The first side of the lens

S116, S216, S316 4-1: The second side of the lens

S117, S217, S317 4-2: The first side of the lens

S118, S218, S318 4-2: The second side of the lens

S119, S219, S319 4-3: The first side of the lens

S120, S220, S320 4-3: The second side of the lens

S121, S221, S321: The first side of the filter

S122, S222, S322: The second side of the filter

Figures 1 and 2 are schematic diagrams of the lens configuration at the wide-angle end and the telephoto end of the first embodiment of the imaging lens according to the present invention.

Figures 3A, 3B, and 3C are Field Curvature, Distortion, and Modulation Transfer Function diagrams at the wide-angle end of the first embodiment of the imaging lens according to the present invention.

Figures 4A, 4B, and 4C are diagrams of field curvature, distortion, and modulation transfer functions at the telephoto end of the first embodiment of the imaging lens according to the present invention.

FIGS. 5 and 6 are schematic diagrams of lens configurations at the wide-angle end and the telephoto end of the second embodiment of the imaging lens according to the present invention.

Figures 7A, 7B, and 7C are diagrams of field curvature, distortion, and modulation transfer functions at the wide-angle end of the second embodiment of the imaging lens according to the present invention.

Figures 8A, 8B, and 8C are diagrams of field curvature, distortion, and modulation transfer functions at the telephoto end of the second embodiment of the imaging lens according to the present invention.

Figures 9 and 10 are schematic diagrams showing the configuration of the imaging lens at the wide-angle end and the telephoto end according to the third embodiment of the imaging lens of the present invention.

Figures 11A, 11B, and 11C are diagrams of field curvature, distortion, and modulation transfer functions at the wide-angle end of the third embodiment of the imaging lens according to the present invention.

Figures 12A, 12B and 12C show the third embodiment of the imaging lens according to the present invention at a telephoto position Field curvature, distortion, and modulation transfer function diagrams at the end.

The invention provides an imaging lens, comprising: a first lens group, the first lens group has positive refractive power; a second lens group, the second lens group has positive refractive power; a third lens group, the third lens group has positive refractive power; and a fourth lens group, the fourth lens group has negative refractive power; wherein light from an object passes through the first lens group, the second lens group, the third lens group from a first side along an axis in sequence The lens group and the fourth lens group are to a second side; wherein the imaging lens may further include a reflective element, the reflective element includes a reflective surface, and the reflective element is disposed along the axis between the first side and the second side; wherein The distance between these lens groups can be changed to allow the imaging lens to change the focal length.

The focal length of the imaging lens of the present invention is a variable focal length, and each embodiment of the imaging lens zooms from the wide-angle end to the telephoto end with a zoom ratio of about 2 times. , so that the effective focal length of the imaging lens of the present invention has, for example, a zoom ratio of 4 times to 8 times compared to the effective focal length of the fixed-focus wide-angle lens. Taking the imaging lens of the first embodiment of the present invention as an example, the effective focal length of the wide-angle end is 14.0754mm, the effective focal length of the telephoto end is 28.0208mm, and the zoom ratio from the wide-angle end to the telephoto end is 1.991 (28.0208mm/14.0754mm= 1.991) times, that is, about 2 times, when it is configured with a fixed-focus wide-angle lens with an effective focal length of 3.52mm in a mobile phone, tablet or other camera device, the effective focal length of the fixed-focus wide-angle lens is the basis of the magnification, which will make the invention The imaging lens has a zoom ratio of 4(14.0754mm/3.52mm=3.999≒4)x to 8(28.0208mm/3.52mm=7.960≒8)x relative to the fixed-focus wide-angle lens with an effective focal length of 3.52mm. However, the present invention is not limited to this. According to another fixed-focus wide-angle lens that is matched with the camera device, it can have a higher, for example, 10 times higher above the zoom ratio.

Please refer to Table 1, Table 2, Table 4, Table 5, Table 7 and Table 8 below, where Table 1, Table 4 and Table 7 are respectively the first to third embodiments of the imaging lens according to the present invention. Table 2, Table 5, and Table 8 are the relevant parameter tables of the aspheric surfaces of the aspheric lenses in Table 1, Table 4, and Table 7, respectively.

Figures 1, 5, and 9 are schematic diagrams of the lens configuration of the first, second, and third embodiments of the imaging lens of the present invention at the wide-angle end, respectively, and Figures 2, 6, and 10 are the first, second, and third embodiments of the imaging lens of the present invention, respectively. The second and third embodiments are schematic diagrams of lens configuration at the telephoto end, wherein the reflecting elements P1, P2, and P3 include an incident surface S11, S21, S31, a reflecting surface S12, S22, S32, and an exit surface S13, S23, S33, the third A lens group LG11, LG21, LG31 has positive refractive power and includes a 1-1 lens L11, L21, L31, a second lens group LG12, LG22, LG32 has positive refractive power and includes a 2-1 lens L12, L22, L32 and a 2-2 lenses L13, L23, L33, the third lens group LG13, LG23, LG33 has positive refractive power and includes a 3-1 lens L14, L24, L34 and a 3-2 lens L15, L25, L35, the fourth lens group LG14, LG24, LG34 have negative refractive power and include a 4-1 lens L16, L26, L36, a 4-2 lens L17, L27, L37 and a 4-3 lens L18, L28, L38.

The reflective elements P1, P2, and P3 are made of glass or plastic materials. The incident surfaces S11, S21, S31 and the exit surfaces S13, S23, and S33 are connected to the reflective surfaces S12, S22, and S32, and the incident surfaces S11, S21, and S31 are connected to the exit surfaces. The surfaces S13, S23, and S33 are perpendicular to each other, and the incident surfaces S11, S21, and S31, the reflection surfaces S12, S22, and S32, and the output surfaces S13, S23, and S33 are all flat surfaces. 1-1 Lenses L11, L21, L31 are meniscus lenses with positive refractive power and are made of glass material. S15, S25, S35 and the second side surfaces S16, S26, and S36 are all aspherical surfaces. 2-1 Lenses L12, L22, L32 are meniscus lenses with positive refractive power, made of glass material, the first side S17, S27, S37 are convex, the second side S18, S28, S38 are concave, S17, S27, S37 and the second side surfaces S18, S28, S38 are all aspherical surfaces. 2-2 Lenses L13, L23 and L33 are meniscus lenses with negative refractive power and are made of glass material. S19, S29, S39 and the second side surfaces S110, S210, S310 are all aspherical surfaces. 3-1 Lenses L14, L24 and L34 are meniscus lenses with negative refractive power and are made of plastic material. S111, S211, S311 and the second side surfaces S112, S212, S312 are all aspherical surfaces. 3-2 Lenses L15, L25, and L35 are biconvex lenses with positive refractive power and are made of plastic materials. S213, S313 and the second side surfaces S114, S214, S314 are all aspherical surfaces. 4-1 Lenses L16, L26 and L36 are meniscus lenses with positive refractive power and are made of plastic material. S115, S215, S315 and the second side surfaces S116, S216, S316 are all aspherical surfaces. 4-2 Lenses L17, L27 and L37 are meniscus lenses with refractive power and are made of plastic material. , S217 , S317 and the second side surfaces S118 , S218 and S318 are all aspherical surfaces. 4-3 Lenses L18, L28, L38 have negative refractive power and are made of plastic material. The second side surfaces S120, S220, and S320 are concave surfaces. aspheric surface.

In addition, the imaging lenses 1, 2, and 3 satisfy at least the following conditions (1) to (8) which are The first condition:

0.1<(DG12W-DG12T)/(fT-fW)<1; (1)

0.1<(DG23T-DG23W)/(fT-fW)<1; (2)

0.1<(DG34W-DG34T)/(fT-fW)<1; (3)

0.1<DG12W/TTL<0.5; (4)

0.1<DG34W/TTL<0.5; (5)

0<DG23W/Dmax<1; (6)

0.3<Dp/Dmax<2; (7)

3.8<TTL/Dmax<5.2; (8)

Among them, DG12W is a distance along the axes AX1, AX2, AX3 of the first lens group LG11, LG21, LG31 and the second lens group LG12, LG22, LG32 at the wide-angle end in the first embodiment to the third embodiment, DG12T is a distance along the axes AX1, AX2, AX3 of the first lens group LG11, LG21, LG31 and the second lens group LG12, LG22, LG32 at the telephoto end in the first to third embodiments, and DG23W is In the first to third embodiments, the second lens group LG12, LG22, LG32 and the third lens group LG13, LG23, LG33 are at a distance along the axes AX1, AX2, AX3 at the wide-angle end, and DG23T is the first In the embodiment to the third embodiment, the second lens group LG12, LG22, LG32 and the third lens group LG13, LG23, LG33 are at a distance along the axes AX1, AX2, AX3 at the telephoto end, DG34W is the first embodiment In the third embodiment, the third lens group LG13, LG23, LG33 and the fourth lens group LG14, LG24, LG34 are at a distance along the axes AX1, AX2, AX3 at the wide-angle end, DG34T is the first embodiment to the third In the third embodiment, the third lens group LG13, LG23, LG33 and the fourth lens group LG14, LG24, LG34 are at the telephoto end along a distance between the axes AX1, AX2, AX3, fW is an effective focal length of the imaging lenses 1, 2, and 3 at the wide-angle end in the first to third embodiments, and fT is the first to third embodiments, when the imaging lenses 1, 2, and 3 are at the telephoto end An effective focal length at the end, TTL is in the first to third embodiments, one of the first sides S15, S25, S35 of the lenses L11, L21, L31 closest to the first side to the imaging planes IMA1, IMA2, IMA3 A spacing on the axes AX1, AX2, AX3, Dmax is the largest optical effective diameter of all the lenses of the imaging lenses 1, 2, 3 in the first to third embodiments, Dp is the first to third embodiments. In the third embodiment, one of the optically effective diameters of the reflective surfaces S12, S22, and S32 is used. The imaging lenses 1, 2 and 3 can effectively shorten the total length of the lens, effectively shorten the thickness of the lens, effectively improve the resolution, effectively correct the aberration, effectively correct the chromatic aberration and realize the optical zoom function.

The first embodiment of the imaging lens of the present invention will now be described in detail. Please refer to FIG. 1 and FIG. 2 at the same time, the imaging lens 1 includes a reflective element P1, an aperture ST1, a first lens group LG11, a first lens group LG11, a first side and a second side in sequence along an axis AX1 Two lens groups LG12, a third lens group LG13, a fourth lens group LG14 and a filter OF1. The reflective element P1 is a structure including an incident surface S11 , a reflective surface S12 and an output surface S13 . The first lens group LG11 includes a 1-1 lens L11. The second lens group LG12 includes a 2-1 lens L12 and a 2-2 lens L13 in sequence from the first side to the second side along the axis AX1. The third lens group LG13 includes a 3-1 lens L14 and a 3-2 lens L15 in sequence from the first side to the second side along the axis AX1. The fourth lens group LG14 includes a 4-1 lens L16, a 4-2 lens L17 and a 4-3 lens L18 in sequence from the first side to the second side along the axis AX1. The incident surface S11 faces an object (not shown) along the axis AX1. When imaging, the light from the object (not shown) enters the reflective element P1 from the incident surface S11, and is reflected by the reflective surface S12 to change the traveling direction, and then pass through in sequence. Outgoing surface S13, aperture ST1, first lens group LG11, second lens group LG12, third lens group LG13, fourth lens group LG14, filters OF1 is finally imaged on an imaging plane IMA1, the imaging plane IMA1 and the incident plane S11 are perpendicular to each other and the outgoing plane S13 is parallel to each other. In the first embodiment, the reflection element P1 is taken as an example but not limited to this, and the reflection element P1 may also be a reflection mirror and only include a reflection surface. In the above description, the first side is the object side, and the second side is the image side.

When the imaging lens 1 is zoomed from the wide-angle end (as shown in Figure 1) to the telephoto end (as shown in Figure 2), the first lens group LG11 is fixed, and the second lens group LG12 moves to the first side along the axis AX1 , the third lens group LG13 moves to the second side along the axis AX1, and the fourth lens group LG14 is fixed, so that the distance between the first lens group LG11 and the second lens group LG12 becomes smaller, and the second lens group LG12 and the third lens group The distance between the groups LG13 is increased, and the distance between the third lens group LG13 and the fourth lens group LG14 is decreased. When the imaging lens 1 of the first embodiment zooms from the wide-angle end (as shown in Figure 1) to the telephoto end (as shown in Figure 2), its zoom ratio is about 2 times (28.0208mm/14.0754mm≒1.99).

The reflective element P1 can act on the axis AX1 or the vertical direction of the axis AX1 to achieve the optical anti-shake effect. The second lens group LG12 and the third lens group LG13 are movable along the axis AX1 for focusing. According to paragraphs 1 to 5 of [Embodiment], wherein: 4-2 lens L17 has negative refractive power; 4-3 lens L18 is a meniscus lens, and its first side S119 is convex; the filter OF1 has its first side S121 and the second side S122 are both planes;

Using the above-mentioned lens, reflective element P1, aperture ST1 and the design that satisfies at least one of the conditions (1) to (8), the imaging lens 1 can effectively shorten the total length of the lens, effectively shorten the thickness of the lens, and effectively improve the resolution. It can effectively correct the aberration, effectively correct the chromatic aberration and realize the optical zoom function.

Table 1 shows that the imaging lens 1 is at the wide-angle end in Fig. 1 and Fig. 2 And the relevant parameter table of each lens at the telephoto end.

The aspheric surface concavity z of the aspheric lens in Table 1 is obtained by the following formula, z=ch ² /{1+[1-(k+1)c ² h ² ] ^1/2 }+Ah ⁴ +Bh ⁶ +Ch ⁸ +Dh ¹⁰ +Eh ¹² +Fh ¹⁴ +Gh ¹⁶ , where: c: curvature; h: vertical distance from any point on the lens surface to the optical axis; k: conic coefficient; A~G: aspheric coefficient.

Table 2 is a table of relevant parameters of the aspheric surface of the aspheric lens in Table 1, where k is the Conic Constant, and A~G are the aspheric coefficients.

Table 3 shows the relevant parameter values of the imaging lens 1 of the first embodiment and the calculated values of the corresponding conditions (1) to (8). It can be seen from Table 3 that the imaging lens 1 of the first embodiment can meet the conditions (1). ) to the requirements of condition (8).

In addition, the optical performance of the imaging lens 1 of the first embodiment can also meet the requirements. It can be seen from FIG. 3A that the field curvature of the imaging lens 1 of the first embodiment is between -0.07mm and 0.08mm at the wide-angle end. It can be seen from FIG. 3B that the distortion of the imaging lens 1 of the first embodiment at the wide-angle end is between -2% and 0%. It can be seen from FIG. 3C that the modulation transfer function value of the imaging lens 1 of the first embodiment at the wide-angle end is between 0.58 and 1.0. It can be seen from FIG. 4A that the field curvature of the imaging lens 1 of the first embodiment at the telephoto end is between -0.25 mm and 0.45 mm. It can be seen from FIG. 4B that the distortion of the imaging lens 1 of the first embodiment at the telephoto end is between -2.5% and 0%. It can be seen from FIG. 4C that the modulation transfer function value of the imaging lens 1 of the first embodiment at the telephoto end is between 0.45 and 1.0. It is obvious that the field curvature and distortion of the imaging lens 1 of the first embodiment can be effectively corrected, and the resolution of the lens can also meet the requirements, thereby obtaining better optical performance.

Please refer to FIG. 5 and FIG. 6 at the same time, the imaging lens 2 sequentially includes a reflective element P2, a first lens group LG21, an aperture ST2, a first lens group along an axis AX2 from a first side to a second side Two lens groups LG22, a third lens group LG23, a fourth lens group LG24 and a filter OF2. The reflective element P2 is a structure including an incident surface S21 , a reflective surface S22 and an output surface S23 . The first lens group LG21 includes a 1-1 lens L21. The second lens group LG22 includes a 2-1 lens L22 and a 2-2 lens L23 in sequence from the first side to the second side along the axis AX2, and the 2-1 lens L22 and the 2-2 lens L23 are cemented. The third lens group LG23 includes a 3-1 lens L24 and a 3-2 lens L25 in sequence from the first side to the second side along the axis AX2. The fourth lens group LG24 includes a 4-1 lens L26, a 4-2 lens L27 and a 4-3 lens L28 in sequence from the first side to the second side along the axis AX2. The incident surface S21 faces an object (not shown) along the axis AX2. When imaging, The light from the object (not shown) enters the reflective element P2 from the incident surface S21, is reflected by the reflective surface S22 and changes its traveling direction, and then passes through the exit surface S23, the first lens group LG21, the aperture ST2, the second lens group LG22, The third lens group LG23, the fourth lens group LG24, and the filter OF2 are finally imaged on an imaging plane IMA2. The imaging plane IMA2 and the incident plane S21 are perpendicular to each other and the outgoing plane S23 is parallel to each other. In the first embodiment, the reflection element P2 is taken as an example but not limited thereto, and the reflection element P2 may also be a reflection mirror and only include a reflection surface. In the above description, the first side is the object side, and the second side is the image side.

When the imaging lens 2 is zoomed from the wide-angle end (as shown in Fig. 5) to the telephoto end (as shown in Fig. 6), the first lens group LG21 is fixed, and the second lens group LG22 moves to the first side along the axis AX2 , the third lens group LG23 moves to the second side along the axis AX2, and the fourth lens group LG24 is fixed, so that the distance between the first lens group LG21 and the second lens group LG22 becomes smaller, and the second lens group LG22 and the third lens group The distance between the groups LG23 is increased, and the distance between the third lens group LG23 and the fourth lens group LG24 is decreased. When the imaging lens 2 of the second embodiment zooms from the wide-angle end (as shown in Figure 5) to the telephoto end (as shown in Figure 6), its zoom ratio is about 2 times (27.9953mm/14.043mm≒1.99).

The reflective element P2 can act on the axis AX2 or the vertical direction of the axis AX2 to achieve the optical anti-shake effect. The second lens group LG22 and the third lens group LG23 are movable along the axis AX2 for focusing. According to paragraphs 1 to 5 of [Embodiment], wherein: 4-2 lens L27 has positive refractive power; 4-3 lens L28 is a biconcave lens, and its first side S219 is concave; the filter OF2 has its first side S221 and the first side S221 Both sides S222 are flat;

Using the above-mentioned lens, reflective element P2, aperture ST2 and the design that satisfies at least one of the conditions (1) to (8), the imaging lens 2 can effectively shorten the total length of the lens, Effectively shorten the thickness of the lens, effectively improve the resolution, effectively correct the aberration, effectively correct the chromatic aberration and realize the optical zoom function.

Table 4 is a table of relevant parameters of each lens when the imaging lens 2 is at the wide-angle end and the telephoto end in Figures 5 and 6, respectively.

The definition of the aspherical surface concavity z of the aspherical lens in Table 4 is the same as the definition of the aspherical surface concavity z of the aspherical lens in Table 1 in the first embodiment, and will not be repeated here.

Table 5 is a table of relevant parameters of the aspheric surface of the aspheric lens in Table 4, where k is the Conic Constant, and A~G are the aspheric coefficients.

Table 6 shows the relevant parameter values of the imaging lens 2 of the second embodiment and the calculated values of the corresponding conditions (1) to (8). It can be seen from Table 6 that the imaging lens 2 of the second embodiment can meet the conditions (1). ) to the requirements of condition (8).

In addition, the optical performance of the imaging lens 2 of the second embodiment can also meet the requirements. It can be seen from FIG. 7A that the field curvature of the imaging lens 2 of the second embodiment is between -0.05mm and 0.03mm at the wide-angle end. It can be seen from FIG. 7B that the distortion of the imaging lens 2 of the second embodiment at the wide-angle end ranges from -1.6% to 0%. It can be seen from FIG. 7C that the modulation transfer function value of the imaging lens 2 of the second embodiment at the wide-angle end is between 0.52 and 1.0. It can be seen from FIG. 8A that the field curvature of the imaging lens 2 of the second embodiment at the telephoto end is between -0.12 mm and 0.14 mm. It can be seen from FIG. 8B that the distortion of the imaging lens 2 of the second embodiment at the telephoto end is between -3% and 0%. It can be seen from FIG. 8C that the modulation transfer function value of the imaging lens 2 of the second embodiment at the telephoto end is between 0.45 and 1.0. It is obvious that the field curvature and distortion of the imaging lens 2 of the second embodiment can be effectively corrected, and the resolution of the lens can also meet the requirements, thereby obtaining better optical performance.

Please refer to FIG. 9 and FIG. 10 at the same time, the imaging lens 3 includes a reflective element P3, an aperture ST3, a first lens group LG31, a first lens group LG31, a first side and a second side in sequence along an axis AX3 Two lens groups LG32, a third lens group LG33, a fourth lens group LG34 and a filter OF3. The reflective element P3 is a structure including an incident surface S31 , a reflective surface S32 and an output surface S33 . The first lens group LG31 includes a 1-1 lens L31. The second lens group LG32 includes a 2-1 lens L32 and a 2-2 lens L33 in sequence from the first side to the second side along the axis AX3. The third lens group LG33 includes a 3-1 lens L34 and a 3-2 lens L35 in sequence from the first side to the second side along the axis AX3. The fourth lens group LG34 includes a 4-1 lens L36, a 4-2 lens L37 and a 4-3 lens L38 in sequence from the first side to the second side along the axis AX3. Incident surface S31 Along the vertical direction of the axis AX3 toward an object (not shown), when imaging, the light from the object (not shown) enters the reflective element P3 from the incident surface S31, and is reflected by the reflective surface S32 to change the traveling direction, and then pass through in sequence The exit surface S33, the aperture ST3, the first lens group LG31, the second lens group LG32, the third lens group LG33, the fourth lens group LG34, and the filter OF3 are finally imaged on an imaging surface IMA3, the imaging surface IMA3 and the incident surface S31 is perpendicular to each other and the exit surface S33 is parallel to each other. In the first embodiment, the reflection element P3 is taken as an example but not limited to this. The reflection element P3 may also be a reflection mirror and only include a reflection surface. In the above description, the first side is not the object side, the object side and the incident surface S31 are located on the same side, and the second side is the image side.

When the imaging lens 3 is zoomed from the wide-angle end (as shown in Fig. 9) to the telephoto end (as shown in Fig. 10), the first lens group LG31 is fixed, and the second lens group LG32 moves to the first side along the axis AX3 , the third lens group LG33 moves to the second side along the axis AX3, and the fourth lens group LG34 is fixed, so that the distance between the first lens group LG31 and the second lens group LG32 becomes smaller, and the second lens group LG32 and the third lens group The distance between the groups LG33 is increased, and the distance between the third lens group LG33 and the fourth lens group LG34 is decreased. When the imaging lens 3 of the third embodiment zooms from the wide-angle end (as shown in Figure 9) to the telephoto end (as shown in Figure 10), its zoom ratio is about 2 times (27.9998mm/14.586mm≒1.92).

The reflective element P3 can act on the axis AX3 or the vertical direction of the axis AX3 to achieve the optical anti-shake effect. The second lens group LG32 and the third lens group LG33 are movable along the axis AX3 for focusing. According to paragraphs 1 to 5 of [Embodiment], wherein: 4-2 lens L37 has negative refractive power; 4-3 lens L38 is a meniscus lens, and its first side S319 is a convex surface; and its first side S321 of filter OF3 and the second side S322 are both planes;

Using the above-mentioned lens, reflecting element P3, aperture ST3 and at least satisfying condition (1) To the design of one of the conditions (8), the imaging lens 3 can effectively shorten the total lens length, effectively shorten the lens thickness, effectively improve the resolution, effectively correct the aberration, effectively correct the chromatic aberration and realize the optical zoom function. .

Table 7 is a table of relevant parameters of each lens when the imaging lens 3 is at the wide-angle end and the telephoto end in Figures 9 and 10, respectively.

The definition of the aspherical surface concavity z of the aspherical lens in Table 7 is the same as the definition of the aspherical surface concavity z of the aspherical lens in Table 1 in the first embodiment, and will not be repeated here.

Table 8 is a table of relevant parameters of the aspherical surface of the aspherical lens in Table 7, where k is the Conic Constant, and A~G are the aspherical coefficients.

Table 8 shows the relevant parameter values of the imaging lens 3 of the third embodiment and the calculated values of the corresponding conditions (1) to (8). It can be seen from Table 8 that the imaging lens 3 of the third embodiment can meet the conditions (1). ) to the requirements of condition (8).

In addition, the optical performance of the imaging lens 3 of the third embodiment can also meet the requirements. It can be seen from FIG. 11A that the field curvature of the imaging lens 3 of the third embodiment at the wide-angle end is between -0.09 mm and 0.07 mm. It can be seen from FIG. 11B that the distortion of the imaging lens 3 of the third embodiment at the wide-angle end is between -1.2% and 0%. It can be seen from FIG. 11C that the modulation transfer function value of the imaging lens 3 of the third embodiment at the wide-angle end is between 0.45 and 1.0. It can be seen from FIG. 12A that the field curvature of the imaging lens 3 of the third embodiment at the telephoto end is between -0.2 mm and 0.45 mm. It can be seen from FIG. 12B that the distortion of the imaging lens 3 of the third embodiment at the telephoto end is between -1.2% and 0%. It can be seen from FIG. 12C that the modulation transfer function value of the imaging lens 3 of the third embodiment at the telephoto end is between 0.40 and 1.0. It is obvious that the field curvature and distortion of the imaging lens 3 of the third embodiment can be effectively corrected, and the resolution of the lens can also meet the requirements, thereby obtaining better optical performance.

In the above embodiment, only one reflective element is arranged between the first side and the first lens group, but it can be understood that another reflective element can also be added between the first lens group and the fourth lens group, or Between the fourth lens group and the second side, that is, one reflecting element is disposed between the first side and the first lens group, and the other reflecting element is disposed between the first lens group and the fourth lens group or the fourth lens Between the group and the second side, in other words, the reflective element can be arranged between the first side and the second side, which should also belong to the scope of the present invention.

In the above-mentioned first and second embodiments, the object (not shown) is arranged on the first side, and the image is formed on the second side, and the object (not shown) can also be arranged on the opposite side of the second side, so that it directly faces the reflective element. The reflective surface of the component can also be imaged on the second side, which should also belong to the scope of the present invention.

In the above-mentioned third embodiment, the object (not shown) is arranged in the vertical direction of the axis directly facing the incident surface of the reflective element, and the image is formed on the second side. The reflective surface directly facing the reflective element can also be imaged on the second side, which should also belong to the scope of the present invention.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone who is familiar with the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention The scope shall be determined by the scope of the appended patent application.

1: Imaging lens

P1: Reflective element

LG11: The first lens group

ST1: Aperture

LG12: Second lens group

LG13: The third lens group

LG14: Fourth lens group

OF1: filter

L11 1-1: Lens

L12 2-1: Lens

L13 2-2: Lens

L14 3-1: Lens

L15 3-2: Lens

L16 4-1: Lens

L17 4-2: Lens

L18 4-3: Lens

IMA1: Imaging plane

AX1: axis

S11: Incident surface

S12: Reflective surface

S13: Exit surface

S14: Aperture Surface

S15 1-1: The first side of the lens

S16 1-1: The second side of the lens

S17 2-1: The first side of the lens

S18 2-1: The second side of the lens

S19 2-2: The first side of the lens

S110 2-2: The second side of the lens

S111 3-1: The first side of the lens

S112 3-1: The second side of the lens

S113 3-2: The first side of the lens

S114 3-2: The second side of the lens

S115 4-1: The first side of the lens

S116 4-1: The second side of the lens

S117 4-2: The first side of the lens

S118 4-2: The second side of the lens

S119 4-3: The first side of the lens

S120 4-3: Second side of lens

S121: The first side of the filter

S122: The second side of the filter

Claims (10)

An imaging lens comprising a first lens group with positive refractive power; a second lens group with positive refractive power; a third lens group with positive refractive power; and a fourth lens group, the fourth lens group has negative refractive power, consisting of; wherein light from an object passes through the first lens group, the second lens group, the first lens group along an axis from a first side in sequence The three lens groups and the fourth lens group are to a second side; wherein the imaging lens further includes a reflective element, the reflective element includes a reflective surface, and the reflective element is disposed along the axis on the first side and the second side The distance between the lens groups can be changed, so that the imaging lens can change the focal length; wherein the imaging lens satisfies at least one of the following conditions: 0.1<DG34W/TTL<0.5; 0<DG23W/Dmax<1; 0.3 <Dp/Dmax<2; 3.8<TTL/Dmax<5.2; wherein, DG23W is a distance along the axis when the second lens group and the third lens group are at the wide-angle end, DG34W is the third lens group and A distance along the axis of the fourth lens group at the wide-angle end, TTL is the distance on the axis from a first side surface of the lens closest to the first side to an imaging surface, and Dmax is all of the imaging lens One of the largest optically effective diameters in the lens, Dp is one of the optically effective diameters of the reflecting surface. An imaging lens consisting of: a first lens group with positive refractive power; a second lens group with positive refractive power; a third lens group with positive refractive power; and a fourth lens group, the fourth lens group has negative refractive power, consisting of; wherein light from an object passes through the first lens group, the second lens group, the third lens group and the a fourth lens group to a second side; wherein the imaging lens further includes a reflection element, the reflection element includes a reflection surface, and the reflection element is disposed between the first side and the second side along the axis; wherein The distance between the lens groups can be changed, so that the imaging lens can change the focal length; the first lens group includes a 1-1 lens, the 1-1 lens is a meniscus lens with positive refractive power, and includes a convex surface along the The axis faces the first side and a concave surface faces the second side along the axis; the second lens group includes a 2-1 lens and a 2-2 lens, and the 2-1 lens is a meniscus lens with positive refractive power , and includes a convex surface facing the first side along the axis and a concave surface facing the second side along the axis, the 2-2 lens is a meniscus lens with negative refractive power, and includes a convex surface facing the axis along the axis The first side and a concave surface face the second side along the axis, the 2-1 lens and the 2-2 lens are sequentially arranged along the axis from the first side to the second side; the third lens The group includes a 3-1 lens and a 3-2 lens, the 3-1 lens is a meniscus lens with negative refractive power, and includes a concave surface facing the first side along the axis and a convex surface facing the first side along the axis On the second side, the 3-2 lens is a biconvex lens with positive refractive power, and includes a convex surface facing the first side along the axis and another convex surface facing the second side along the axis, the 3-1 lens and the 3-2 The lenses are sequentially arranged along the axis from the first side to the second side; The fourth lens group includes a 4-1 lens, a 4-2 lens and a 4-3 lens, the 4-1 lens is a meniscus lens with positive refractive power, and includes a concave surface facing the first lens along the axis side and a convex surface facing the second side along the axis, the 4-2 lens is a meniscus lens with refractive power, and includes a concave surface facing the first side along the axis and a convex surface facing the first side along the axis On two sides, the 4-3 lens has negative refractive power and includes a concave surface along the axis toward the second side, the 4-1 lens, the 4-2 lens and the 4-3 lens along the axis from the first One side to the second side are arranged in order. An imaging lens, comprising: a first lens group, the first lens group has positive refractive power; a second lens group, the second lens group has positive refractive power; a third lens group, the third lens group has positive refractive power and a fourth lens group, the fourth lens group having negative refractive power, consisting of; wherein light from an object passes through the first lens group, the second lens group, the The third lens group and the fourth lens group are to a second side; wherein the imaging lens further includes a reflective element, the reflective element includes a reflective surface, and the reflective element is disposed along the axis on the first side and the first side between the two sides; wherein the distance between the lens groups can be changed, so that the imaging lens can change the focal length; wherein the reflective element is disposed along the axis between the first side and the first lens group, the second lens The group and the third lens group are movable along the axis to focus the imaging lens. An imaging lens, comprising: a first lens group, the first lens group has positive refractive power; A second lens group with positive refractive power; a third lens group with positive refractive power; and a fourth lens group with negative refractive power, consisting of; The light of an object passes through the first lens group, the second lens group, the third lens group and the fourth lens group in sequence along an axis from a first side to a second side; wherein the imaging lens is further Including a reflective element, the reflective element includes a reflective surface, the reflective element is arranged between the first side and the second side along the axis; wherein the distance between the lens groups can be changed, so that the imaging lens changes Focal length; wherein the reflective element can act on the axis or the vertical direction of the axis to achieve optical anti-shake. An imaging lens, comprising: a first lens group, the first lens group has positive refractive power; a second lens group, the second lens group has positive refractive power; a third lens group, the third lens group has positive refractive power and a fourth lens group, the fourth lens group having negative refractive power, consisting of; wherein light from an object passes through the first lens group, the second lens group, the The third lens group and the fourth lens group are to a second side; wherein the imaging lens further includes a reflective element, the reflective element includes a reflective surface, and the reflective element is disposed along the axis on the first side and the first side between two sides; wherein the distance between the lens groups can be changed, so that the imaging lens can change the focal length; The second lens group moves to the first side along the axis, the third lens group moves to the second side along the axis, and the first lens group and the fourth lens group are fixed to make the imaging The lens is zoomed from a wide-angle end to a telephoto end. An imaging lens, comprising: a first lens group, the first lens group has positive refractive power; a second lens group, the second lens group has positive refractive power; a third lens group, the third lens group has positive refractive power and a fourth lens group, the fourth lens group having negative refractive power, consisting of; wherein light from an object passes through the first lens group, the second lens group, the The third lens group and the fourth lens group are to a second side; wherein the imaging lens further includes a reflective element, the reflective element includes a reflective surface, and the reflective element is disposed along the axis on the first side and the first side between two sides; wherein the distance between the lens groups can be changed, so that the imaging lens can change the focal length; wherein the imaging lens at least satisfies one of the following conditions: 0.1<(DG12W-DG12T)/(fT-fW)<1; 0.1<(DG23T-DG23W)/(fT-fW)<1; 0.1<(DG34W-DG34T)/(fT-fW)<1; DG12W is the first lens group and the second lens group at the wide-angle end DG12T is a distance along the axis when the first lens group and the second lens group are at the telephoto end, DG23W is the second lens group and the third lens group at the wide-angle end DG23T is a distance along the axis when the second lens group and the third lens group are at the telephoto end, DG34W is the third lens group and the fourth lens group in A distance along the axis at the wide-angle end, DG34T is a distance along the axis when the third lens group and the fourth lens group are at the telephoto end, fW is an effective focal length of the imaging lens at the wide-angle end, fT is an effective focal length of the imaging lens at the telephoto end. The imaging lens described in item 1, item 3, item 4, item 5 or item 6 of the application scope, wherein the fourth lens group comprises a 4-2 lens and a 4-3 lens, the 4 The -2 lens has negative refractive power, and the 4-3 lens further includes a convex surface facing the first side along the axis. The imaging lens described in item 1, item 3, item 4, item 5 or item 6 of the application scope, wherein the fourth lens group comprises a 4-2 lens and a 4-3 lens, the 4 The -2 lens has positive refractive power, and the 4-3 lens further includes a concave surface facing the first side along the axis. The imaging lens described in item 1, item 3, item 4, item 5 or item 6 of the application scope, wherein the second lens group comprises a 2-1 lens and a 2-2 lens, the 2 The -1 lens and this 2-2 lens are cemented. The imaging lens according to any one of claims 2 to 6 of the application scope, wherein the imaging lens satisfies at least one of the following conditions: 0.1<DG12W/TTL<0.5; 0.1<DG34W/TTL<0.5; 0 <DG23W/Dmax<1; 0.3<Dp/Dmax<2; 3.8<TTL/Dmax<5.2; wherein, DG12W is a distance along the axis of the first lens group and the second lens group at the wide-angle end, DG23W is a distance along the axis when the second lens group and the third lens group are at the wide-angle end, and DG34W is the third lens group and the fourth lens group at the wide-angle end A distance along the axis, TTL is a distance from a first side surface of the lens closest to the first side to an imaging surface on the axis, Dmax is a maximum optical effective diameter of all lenses of the imaging lens, Dp is an optical effective diameter of the reflecting surface.

Images