TW202016599A - Lens assembly - Google Patents

Abstract

A lens assembly includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens. The first lens is with positive refractive power and includes a convex surface facing an object side. The second lens is with negative refractive power. The third lens is with positive refractive power and includes a convex surface facing the object side. The fourth lens is with positive refractive power. The fifth lens is with negative refractive power and includes a concave surface facing an image side. The first lens, the second lens, the third lens, the fourth lens, and the fifth lens are arranged in order from the object side to the image side along an optical axis. The lens assembly satisfies: 10 mm <f₃ +f₄ < 15 mm; wherein f₃ is an effective focal length of the third lens and f₄ is an effective focal length of the fourth lens.

Description

Imaging lens (27)

The invention relates to an imaging lens.

The current development trend of imaging lenses, in addition to the continuous development of miniaturization, with different application needs, also need to have high-resolution capabilities, conventional imaging lenses can no longer meet today's needs, and need another new architecture The imaging lens can meet the requirements of miniaturization and high resolution at the same time.

In view of this, the main purpose of the present invention is to provide an imaging lens with a shorter overall lens length and higher resolution, but still having good optical performance.

The imaging lens of the present invention includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens. The first lens has positive refractive power and includes a convex surface facing an object side. The second lens has negative refractive power. The third lens has positive refractive power and includes a convex surface facing the object side. The fourth lens has positive refractive power. The fifth lens has negative refractive power and includes a concave surface facing an image side. The first lens, the second lens, the third lens, the fourth lens, and the fifth lens are sequentially arranged along the optical axis from the object side to the image side. The imaging lens satisfies the following conditions: 10mm<f ₃ +f ₄ <15mm; where f ₃ is the effective focal length of one of the third lenses, and f ₄ is the effective focal length of one of the fourth lenses.

Another imaging lens of the present invention includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens. The first lens has positive refractive power and includes a convex surface facing an object side. The second lens has negative refractive power. The third lens has positive refractive power and includes a convex surface facing the object side. The fourth lens has positive refractive power. The fifth lens has negative refractive power and includes a concave surface facing an image side. The first lens, the second lens, the third lens, the fourth lens, and the fifth lens are sequentially arranged along the optical axis from the object side to the image side. The imaging lens satisfies the following conditions: 5<(R ₁₁ +R ₁₂ )/(R ₂₁ +R ₂₂ )<15; where R ₁₁ is the radius of curvature of one of the object sides of the first lens, and R ₁₂ is the A radius of curvature of one image side, R ₂₁ is a radius of curvature of one object side of the second lens, and R ₂₂ is a radius of curvature of one image side of the second lens.

The imaging lens satisfies the following conditions: -2<f/f ₅ <0;-2.5<f ₅ /f ₁ <0; where f ₁ is the effective focal length of one of the first lenses and f ₅ is effective of one of the fifth lenses Focal length, f is one of the effective focal lengths of the imaging lens.

The imaging lens satisfies the following conditions: 0.4<BFL/TTL<0.55; where BFL is the distance from the image side of the fifth lens to an imaging plane on the optical axis, and TTL is the object side of the first lens to the imaging plane One pitch on the optical axis.

The imaging lens satisfies the following conditions: -1<R ₂₁ /R ₂₂ <-0.5; where R ₂₁ is one of the radius of curvature of one side of the object of the second lens, and R ₂₂ is one of the radius of curvature of one side of the image of the second lens .

The imaging lens satisfies the following conditions: 0<R ₄₁ /R ₁₁ <2; where R ₁₁ is one of the radii of curvature of one side of the object of the first lens, and R ₄₁ is one of the radii of curvature of one side of the object of the fourth lens.

The imaging lens satisfies the following conditions: -5<f/f ₂ <-3; where f ₂ is one of the effective focal lengths of the second lens, and f is one of the effective focal lengths of the imaging lens.

The imaging lens satisfies the following conditions: 10mm<f ₄₅ <15mm; where f ₄₅ is the effective focal length of the combination of the fourth lens and the fifth lens.

The first lens is a meniscus lens, which may further include a concave surface facing the image side, the second lens is a biconcave lens including a concave surface facing the object side and the other concave surface facing the image side, and the fourth lens is a biconvex lens including a convex surface The fifth lens is a double concave lens toward the object side and the other convex surface toward the image side, and may further include a concave surface toward the object side.

The third lens is a biconvex lens or a meniscus lens, and the imaging lens satisfies the following conditions: -5<(R ₃₁ +R ₃₂ )/(R ₄₁ +R ₄₂ )<2; where R ₃₁ is one of the third lenses The radius of curvature of one of the object sides, R ₃₂ is the radius of curvature of one of the image sides of the third lens, R ₄₁ is the radius of curvature of one of the object sides of the fourth lens, and R ₄₂ is the curvature of one of the image sides of the fourth lens radius.

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

1, 2, 3, 4 ‧‧‧ imaging lens

L11, L21, L31, L41 ‧‧‧ first lens

L12, L22, L32, L42 ‧‧‧ second lens

L13, L23, L33, L43 ‧‧‧ third lens

L14, L24, L34, L44 ‧‧‧ fourth lens

L15, L25, L35, L45‧Fifth lens

ST1, ST2, ST3, ST4 ‧‧‧ aperture

OF1, OF2, OF3, OF4‧‧‧‧filter

OA1, OA2, OA3, OA4 ‧‧‧ optical axis

IMA1, IMA2, IMA3, IMA4 ‧‧‧ imaging surface

S11, S21, S31, S41

S12, S22, S32, S42 ‧‧‧ Image side of the first lens

S13, S23, S33, S43

S14, S24, S34, S44

S15, S25, S35, S45‧‧‧‧Image side of the second lens

S16, S26, S36, S46‧‧‧‧object side of third lens

S17, S27, S37, S47‧‧‧‧Image side of third lens

S18, S28, S38, S48‧‧‧‧object side of fourth lens

S19, S29, S39, S49‧‧‧‧Image side of fourth lens

S110, S210, S310, S410

S111, S211, S311, S411‧‧‧‧Image side of fifth lens

S112, S212, S312, S412 ‧‧‧ filter side

S113, S213, S313, S413 ‧‧‧ filter image side

FIG. 1 is a schematic diagram of the lens configuration and optical path of the first embodiment of the imaging lens according to the present invention.

FIG. 2A is a field curvature diagram of the first embodiment of the imaging lens according to the present invention.

FIG. 2B is a distortion diagram of the first embodiment of the imaging lens according to the present invention.

FIG. 2C is a modulation transfer function diagram of the first embodiment of the imaging lens of the present invention.

FIG. 3 is a lens configuration and optical path diagram of the second embodiment of the imaging lens according to the present invention Figure.

FIG. 4A is a field curvature diagram of the second embodiment of the imaging lens according to the present invention.

FIG. 4B is a distortion diagram of the second embodiment of the imaging lens according to the present invention.

FIG. 4C is a modulation transfer function diagram of the second embodiment of the imaging lens of the present invention.

FIG. 5 is a schematic diagram of the lens configuration and optical path of the third embodiment of the imaging lens according to the present invention.

FIG. 6A is a field curvature diagram of the third embodiment of the imaging lens according to the present invention.

FIG. 6B is a distortion diagram of the third embodiment of the imaging lens according to the present invention.

FIG. 6C is a modulation transfer function diagram of the third embodiment of the imaging lens according to the present invention.

FIG. 7 is a schematic diagram of the lens configuration and optical path of the fourth embodiment of the imaging lens according to the present invention.

FIG. 8A is a field curvature diagram of the fourth embodiment of the imaging lens according to the present invention.

FIG. 8B is a distortion diagram of the fourth embodiment of the imaging lens according to the present invention.

FIG. 8C is a modulation transfer function diagram of the fourth embodiment of the imaging lens of the present invention.

The invention provides an imaging lens, comprising: a first lens with positive refractive power, the first lens including a convex surface facing an object side; a second lens with negative refractive power; and a third lens with positive refractive power, the third lens includes A convex surface faces the object side; a fourth lens has positive refractive power; and a fifth lens has negative refractive power, the fifth lens includes a concave surface facing an image side; wherein the first lens, the second lens, the third lens, the fourth The lens and the fifth lens are arranged in order from the object side to the image side along an optical axis; wherein the imaging lens satisfies the following conditions: 10mm<f ₃ +f ₄ <15mm; where f ₃ is one of the effective focal lengths of the third lens, f ₄ is the effective focal length of one of the fourth lenses.

The present invention provides another imaging lens, including: a first lens having positive refractive power, the first lens including a convex surface facing an object side; a second lens having negative refractive power; a third lens having positive refractive power, the third lens It includes a convex surface facing the object side; a fourth lens with positive refractive power; and a fifth lens with negative refractive power, the fifth lens includes a concave surface facing an image side; wherein the first lens, the second lens, the third lens, the first The four lenses and the fifth lens are arranged in order from the object side to the image side along an optical axis; wherein the imaging lens satisfies the following conditions: 5<(R ₁₁ +R ₁₂ )/(R ₂₁ +R ₂₂ )<15; where, R ₁₁ is the radius of curvature of one of the object sides of the first lens, R ₁₂ is the radius of curvature of one of the image sides of the first lens, R ₂₁ is the radius of curvature of one of the object sides of the second lens, and R ₂₂ is the second One of the lenses has a radius of curvature on the image side.

Please refer to Table 1, Table 2, Table 4, Table 5, Table 7, Table 8, Table 10 and Table 11 below, of which Table 1, Table 4, Table 7 and Table 10 are the first The relevant parameter table of each lens of the first to fourth embodiments, Table 2, Table 5, Table 8 and Table 11 are the correlation of the aspheric surface of each lens in Table 1, Table 4, Table 7 and Table 10 respectively Parameters Table.

Figures 1, 3, 5, and 7 are schematic diagrams of lens configurations and optical paths of the first, second, third, and fourth embodiments of the imaging lens of the present invention, wherein the first lenses L11, L21, L31, L41 have positive refractive power made of plastic Made of material, the object side surfaces S11, S21, S31, S41 are convex surfaces, and the object side surfaces S11, S21, S31, S41 and the image side surfaces S12, S22, S32, S42 are all aspherical surfaces.

The second lenses L12, L22, L32, and L42 have negative refractive power and are made of glass. The object side surfaces S14, S24, S34, S44 and the image side surfaces S15, S25, S35, S45 are all aspherical surfaces.

The third lens L13, L23, L33, L43 has a positive refractive power made of glass material, the object side surfaces S16, S26, S36, S46 are convex surfaces, the object side surfaces S16, S26, S36, S46 and the image side surfaces S17, S27, S37, S47 are all aspherical surfaces.

The fourth lenses L14, L24, L34, L44 have a positive refractive power and are made of glass material, and the object side surfaces S18, S28, S38, S48 and the image side surfaces S19, S29, S39, S49 are all aspherical surfaces.

The fifth lenses L15, L25, L35, and L45 have negative refractive power and are made of glass materials. The image side surfaces S111, S211, S311, and S411 are concave surfaces, and the object side surfaces S110, S210, S310, S410 and the image side surfaces S111, S211, S311, S411 are all aspherical surfaces.

In addition, the imaging lenses 1, 2, 3, and 4 satisfy at least one of the following conditions: 10mm<f ₃ +f ₄ <15mm (1)

5<(R ₁₁ +R ₁₂ )/(R ₂₁ +R ₂₂ )<15 (2)

-2<f/f ₅ <0 (3)

-2.5<f ₅ /f ₁ <0 (4)

0.4<BFL/TTL<0.55 (5)

-1<R ₂₁ /R ₂₂ <-0.5 (6)

0<R ₄₁ /R ₁₁ <2 (7)

-5<f/f ₂ <-3 (8)

-5<(R ₃₁ +R ₃₂ )/(R ₄₁ +R ₄₂ )<2 (9)

10mm<f ₄₅ <15mm (10)

Where f is the effective focal length of one of the imaging lenses 1, 2, 3, and 4 in the first to fourth embodiments, and f ₁ is the first lens L11, L21, L31 in the first to fourth embodiments. One of the effective focal lengths of L41, f ₂ is one of the effective focal lengths of the second lenses L12, L22, L32, and L42 in the first to fourth embodiments, and f ₃ is the third lens of the first to fourth embodiments. One of the effective focal lengths of L13, L23, L33, and L43, f ₄ is the effective focal length of one of the fourth lenses L14, L24, L34, L44 in the first to fourth embodiments, and f ₅ is the first to fourth embodiments In the embodiment, one of the fifth lenses L15, L25, L35, and L45 has an effective focal length, and f ₄₅ is the fourth lens L14, L24, L34, L44 and the fifth lens L15, L25, respectively in the first to fourth embodiments. one combination of L35, L45 effective focal length, R ₁₁ is the first embodiment to the fourth embodiment, the first lens L11, L21, L31, L41 of the object side surface S11, S21, S31, S41, one radius of curvature, R ₁₂ Examples of the first embodiment to the fourth embodiment of the first embodiment lens L11, L21, L31, L41 of the image side surface S12, S22, S32, S42, one radius of curvature, R ₂₁ is the first embodiment to the fourth embodiment of the second lens L12, object side surface L22, L32, L42 of S14, S24, S34, S44, one radius of curvature, R ₂₂ is the first embodiment to the fourth embodiment of the second lens L12, L22, L32, L42 of the image side surface S15, S25, S35, S45, one radius of curvature, R ₃₁ is the first embodiment to the third embodiment of the lens L13 of the fourth embodiment, L23, L33, L43 of the object side surface S16, S26, S36, S46, one radius of curvature, R ₃₂ is the radius of curvature of one of the image sides S17, S27, S37, and S47 of the third lenses L13, L23, L33, L43 in the first to fourth embodiments, and R ₄₁ is the first to fourth embodiments The radius of curvature of one of the object sides S18, S28, S38, and S48 of the middle and fourth lenses L14, L24, L34, L44, and R ₄₂ is one of the fourth lenses L14, L24, L34, L44 of the first to fourth embodiments The radius of curvature of one of the image sides S19, S29, S39, S49, TTL is the object side S11, S21, S31, S41 of the first lens L11, L21, L31, L41 in the first to fourth embodiments to the imaging plane IMA1 , IMA2, IMA3, IMA4 on the optical axis OA1, OA2, OA3, OA4 one pitch, BFL is the first to fourth embodiments of the fifth lens L15, L25, L35, L45 image side S111, S211, S311, S411 to the imaging plane IMA1, IMA2, IMA3, IMA4 on the optical axis OA1, O One pitch on A2, OA3, OA4. The imaging lens 1, 2, 3, 4 can effectively shorten the total length of the lens, effectively improve the resolution, and effectively correct aberrations.

The first embodiment of the imaging lens of the present invention will now be described in detail. Referring to FIG. 1, the imaging lens 1 includes a first lens L11, an aperture ST1, a second lens L12, a third lens L13, a first lens in order from an object side to an image side along an optical axis OA1 Four lenses L14, a fifth lens L15 and a filter OF1. When imaging, the light from the object side is finally imaged on an imaging surface IMA1. According to the first to eighth paragraphs of the [Embodiment], the first lens L11 may be a meniscus lens with a concave image side S12; the second lens L12 may be a biconcave lens with an object side S14 concave. The side S15 is concave; the third lens L13 can be a more meniscus lens, and its image side S17 is concave; the fourth lens L14 can be a more biconvex lens, whose object side S18 is convex, and the image side S19 is convex; the fifth lens L15 may be a more biconcave lens, and its object side S110 is concave; the filter OF1 has a flat object surface S112 and an image side S113.

Use the above lens, aperture ST1 and satisfy at least condition (1) to condition (10) The one-condition design enables the imaging lens 1 to effectively shorten the total lens length, effectively improve the resolution, and effectively correct aberrations.

Table 1 is a table of related parameters of each lens of the imaging lens 1 in FIG. 1. The data in Table 1 shows that the effective focal length of the imaging lens 1 of the first embodiment is equal to 12.000 mm, the aperture value is equal to 2.89, and the total lens length is equal to 12.029 mm. The field of view is equal to 27.3 degrees.

The aspherical surface concave degree z of each 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: aspherical coefficient.

Table 2 is the related parameter table of the aspherical surface of each lens in Table 1, where k is the conic constant and A~G are the aspherical coefficients.

Table 3 shows the related parameter values of the imaging lens 1 of the first embodiment and the calculated values of the corresponding conditions (1) to (10). From Table 3, it can be seen that the imaging lens 1 of the first embodiment can satisfy the condition (1 ) To the requirements of condition (10).

In addition, the optical performance of the imaging lens 1 of the first embodiment can also meet the requirements, which can be seen from FIGS. 2A to 2C. Shown in FIG. 2A is a field curvature diagram of the imaging lens 1 of the first embodiment. Shown in FIG. 2B is a distortion diagram of the imaging lens 1 of the first embodiment. Shown in FIG. 2C is a modulation transfer function (Modulation Transfer Function) diagram of the imaging lens 1 of the first embodiment.

As can be seen from FIG. 2A, the imaging lens 1 of the first embodiment has a wavelength of 0.430 μm, 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm, and the sagittal (Tangential) direction. ) The field curvature in the direction is between -0.02mm and 0.14mm.

It can be seen from Figure 2B (the six lines in the figure almost overlap, so that there seems to be almost only one line), the imaging lens 1 of the first embodiment has a pair of wavelengths of 0.430 μm, 0.470 μm, 0.510 μm, 0.555 μm, The distortion produced by 0.610μm and 0.650μm light is between 0% and 1.2%.

As can be seen from FIG. 2C, the imaging lens 1 of the first embodiment pairs the light with a wavelength range of 0.4300 μm to 0.6500 μm in the tangential direction and sagittal respectively (Sagittal) direction, the field of view height is 0.0000mm, 1.1656mm, 2.3312mm, 2.6226mm, 2.9140mm, the spatial frequency is between 0 lp/mm to 83 lp/mm, and its modulation transfer function value is between 0.67 and 1.0 between.

It is obvious that the field curvature and distortion of the imaging lens 1 of the first embodiment can be effectively corrected, and the lens resolution can also meet the requirements, thereby obtaining better optical performance.

Please refer to FIG. 3, which is a schematic diagram of a lens configuration and an optical path according to the second embodiment of the imaging lens of the present invention. The imaging lens 2 includes a first lens L21, an aperture ST2, a second lens L22, a third lens L23, a fourth lens L24, a first lens in order from an object side to an image side along an optical axis OA2 Five lenses L25 and a filter OF2. When imaging, the light from the object side is finally imaged on an imaging surface IMA2. According to paragraphs 1 to 8 of the embodiment, the first lens L21 can be a meniscus lens with an image side S22 as a concave surface; the second lens L22 can be a biconcave lens with an object side S24 as a concave surface The side S25 is concave; the third lens L23 can be a more meniscus lens, and its image side S27 is concave; the fourth lens L24 can be a more biconvex lens, whose object side S28 is convex, and the image side S29 is convex; the fifth lens The L25 may be a more biconcave lens, and its object side S210 is concave; the filter OF2 has both its object side S212 and the image side S213 being flat.

By using the lens, the aperture ST2 and the design satisfying at least one of the conditions (1) to (10), the imaging lens 2 can effectively shorten the total lens length, effectively improve the resolution, and effectively correct the aberration.

Table 4 is a table of related parameters of each lens of the imaging lens 2 in FIG. 3, and the data in Table 4 shows that the effective focal length of the imaging lens 2 of the second embodiment is equal to 11.662 mm, and the aperture The value is equal to 2.89, the total lens length is equal to 11.901mm, and the field of view is equal to 28 degrees.

The definition of the aspherical surface concavity z of each lens in Table 4 is the same as the definition of the aspherical surface concavity z of each lens in Table 1 in the first embodiment, which is not used here Repeat.

Table 5 is the related parameter table of the aspherical surface of each lens in Table 4, where k is the conic constant and A~G are the aspherical 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 (10). As can be seen from Table 6, the imaging lens 2 of the second embodiment can satisfy the condition (1 ) To the requirements of condition (10).

In addition, the optical performance of the imaging lens 2 of the second embodiment can also meet the requirements, which can be seen from FIGS. 4A to 4C. FIG. 4A is a field curvature diagram of the imaging lens 2 of the second embodiment. Shown in FIG. 4B is a distortion diagram of the imaging lens 2 of the second embodiment. Shown in FIG. 4C is a modulation transfer function diagram of the imaging lens 2 of the second embodiment.

It can be seen from FIG. 4A that the imaging lens 2 of the second embodiment has a wavelength of 0.430 μm, 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm, and the sagittal (Tangential) direction. ) The field curvature in the direction is between -0.03mm and 0.08mm.

It can be seen from Fig. 4B (the six lines in the figure almost overlap so that there seems to be almost only one line), the imaging lens 2 of the second embodiment has a pair of wavelengths of 0.430 μm, 0.470 μm, 0.510 μm, 0.555 μm, The distortion produced by 0.610μm and 0.650μm light is between 0% and 2.0%.

It can be seen from FIG. 4C that the imaging lens 2 of the second embodiment is for the light with a wavelength range of 0.4300 μm to 0.6500 μm, respectively in the meridional (Tangential) direction and sagittal (Sagittal) direction, and the field of view height is 0.0000 mm, 0.8742mm, 1.4570mm, 2.0398mm, 2.3312mm, 2.6226mm, 2.9140mm, the spatial frequency is between 0 lp/mm to 83 lp/mm, and its modulation transfer function value is between 0.67 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 lens resolution can also meet the requirements, thereby obtaining better optical performance.

Please refer to FIG. 5. FIG. 5 is a schematic diagram of a lens configuration and an optical path of a third embodiment of the imaging lens according to the present invention. The imaging lens 3 moves from an object side to an object along an optical axis OA3 The image side includes, in order, a first lens L31, an aperture ST3, a second lens L32, a third lens L33, a fourth lens L34, a fifth lens L35, and a filter OF3. When imaging, the light from the object side is finally imaged on an imaging surface IMA3. According to paragraphs 1 to 8 of the embodiment, the first lens L31 may be a meniscus lens with an image side S32 as a concave surface; the second lens L32 may be a biconcave lens with an object side S34 as a concave surface The side S35 is concave; the third lens L33 can be more biconvex, and its image side S37 is convex; the fourth lens L34 can be more biconvex, its object side S38 is convex, and the image side S39 is convex; the fifth lens L35 can be For a biconcave lens, the object side S310 is concave; the filter OF3 has a flat object surface S312 and an image side S313.

By using the lens, the aperture ST3, and the design satisfying at least one of the conditions (1) to (10), the imaging lens 3 can effectively shorten the total lens length, effectively improve the resolution, and effectively correct the aberration.

Table 7 is a table of related parameters of each lens of the imaging lens 3 in FIG. 5, the data in Table 7 shows that the effective focal length of the imaging lens 3 of the third embodiment is equal to 11.410mm, the aperture value is equal to 2.89, the total lens length is equal to 11.838mm, The field of view is equal to 28.6 degrees.

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

Table 8 is the related parameter table of the aspherical surface of each lens in Table 7, where k is the conic constant and A~G are the aspherical coefficients.

Table 9 shows the related parameter values of the imaging lens 3 of the third embodiment and the calculated values of the corresponding conditions (1) to (10). As can be seen from Table 9, the imaging lens 3 of the third embodiment can satisfy the condition (1 ) To the requirements of condition (10).

In addition, the optical performance of the imaging lens 3 of the third embodiment can also meet the requirements, which can be seen from FIGS. 6A to 6C. FIG. 6A is a field curvature diagram of the imaging lens 3 of the third embodiment. Shown in FIG. 6B is a distortion diagram of the imaging lens 3 of the third embodiment. Shown in FIG. 6C is a modulation transfer function (Modulation Transfer Function) diagram of the imaging lens 3 of the third embodiment.

It can be seen from FIG. 6A that the imaging lens 3 of the third embodiment has a wavelength of 0.430 μm, 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm, and the sagittal (Tangential) direction. ) The field curvature in the direction is between -0.03mm and 0.09mm between.

It can be seen from Figure 6B (the six lines in the figure almost overlap so that there seems to be almost only one line), the imaging lens 3 of the third embodiment has a pair of wavelengths of 0.430 μm, 0.470 μm, 0.510 μm, 0.555 μm, The distortion produced by 0.610μm and 0.650μm light is between 0% and 1.5%.

As can be seen from FIG. 6C, the imaging lens 3 of the third embodiment pairs the light with a wavelength range of 0.4300 μm to 0.6500 μm in the meridional (Tangential) direction and sagittal (Sagittal) direction, and the field of view height is 0.0000 mm, 0.8742mm, 1.4570mm, 2.0398mm, 2.3312mm, 2.6226mm, 2.9140mm, the spatial frequency is between 0 lp/mm to 83 lp/mm, and its modulation transfer function value is between 0.69 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 lens resolution can also meet the requirements, thereby obtaining better optical performance.

Please refer to FIG. 7, which is a schematic diagram of a lens configuration and optical path of a fourth embodiment of an imaging lens according to the present invention. The imaging lens 4 includes a first lens L41, an aperture ST4, a second lens L42, a third lens L43, a fourth lens L44, a first lens in order from an object side to an image side along an optical axis OA4 Five lenses L45 and one filter OF4. When imaging, the light from the object side is finally imaged on an imaging surface IMA4. According to the first to eighth paragraphs of the [Embodiment], the first lens L41 can be a meniscus lens with an image side S42 as a concave surface; the second lens L42 can be a biconcave lens with an object side S44 as a concave surface The side S45 is concave; the third lens L43 can be a more meniscus lens, and its image side S47 is concave; the fourth lens L44 can be a more biconvex lens, whose object side S48 is convex, and the image side S49 is convex; the fifth lens L45 It can be a meniscus lens, the object side S410 of which is convex; the filter OF4 has an object side S412 and an image side S413 that are both flat.

By using the lens, the aperture ST4 and the design satisfying at least one of the conditions (1) to (10), the imaging lens 4 can effectively shorten the total lens length, effectively improve the resolution, and effectively correct the aberration.

Table 10 is a table of related parameters of each lens of the imaging lens 4 in FIG. 7. The data in Table 10 shows that the effective focal length of the imaging lens 4 of the fourth embodiment is equal to 11.704mm, the aperture value is equal to 2.91, the total lens length is equal to 12.006mm, The field of view is equal to 2.7.9 degrees.

The definition of the aspheric surface concavity z of each lens in Table 10 is the same as the definition of the aspheric surface concavity z of each lens in Table 1 in the first embodiment, which will not be repeated here.

Table 11 is a table of related parameters of the aspherical surfaces of the lenses in Table 10, where k is the conic constant and A~G are the aspherical coefficients.

Table 12 shows the related parameter values of the imaging lens 4 of the fourth embodiment and the calculated values of the corresponding conditions (1) to (10). As can be seen from Table 12, the imaging lens 4 of the fourth embodiment can satisfy the conditions (1) To the requirements of condition (10).

In addition, the optical performance of the imaging lens 4 of the fourth embodiment can also meet the requirements, which can be seen from FIGS. 8A to 8C. FIG. 8A is a field curvature diagram of the imaging lens 4 of the fourth embodiment. Shown in FIG. 8B is a distortion diagram of the imaging lens 4 of the fourth embodiment. Shown in FIG. 8C is a modulation transfer function (Modulation Transfer Function) diagram of the imaging lens 4 of the fourth embodiment.

It can be seen from FIG. 8A that the imaging lens 4 of the fourth embodiment has a wavelength of 0.430 μm, 0.470 μm, 0.510 μm, 0.555 μm, 0.610 μm, and 0.650 μm, and the sagittal (Tangential) direction. ) The field curvature in the direction is between -0.03mm and 0.09mm.

As can be seen from Figure 8B (the six lines in the figure almost overlap, so that there seems to be almost only one line), the imaging lens 4 of the fourth embodiment has a pair of wavelengths of 0.430 μm, 0.470 μm, 0.510 μm, 0.555 μm, The distortion produced by 0.610μm and 0.650μm light is between 0% and 1.6%.

As can be seen from FIG. 8C, the imaging lens 4 of the fourth embodiment pairs the light with a wavelength range of 0.4300 μm to 0.6500 μm in the meridional (Tangential) direction and sagittal (Sagittal) direction, and the field of view height is 0.0000 mm, 0.8742mm, 1.4570mm, 2.0398 mm, 2.3312mm, 2.6226mm, 2.9140mm, the spatial frequency is between 0 lp/mm to 83 lp/mm, and its modulation transfer function value is between 0.68 and 1.0.

It is obvious that the field curvature and distortion of the imaging lens 4 of the fourth embodiment can be effectively corrected, and the lens resolution can also meet the requirements, thereby obtaining better optical performance.

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

1‧‧‧Imaging lens

L11‧‧‧First lens

L12‧‧‧Second lens

L13‧‧‧third lens

L14‧‧‧Fourth lens

L15‧‧‧fifth lens

ST1‧‧‧Aperture

OF1‧‧‧filter

OA1‧‧‧Optical axis

IMA1‧‧‧Imaging surface

S11‧‧‧Side of the first lens

S12‧‧‧The first lens image side

S13‧‧‧Aperture

S14‧‧‧Second lens object side

S15‧‧‧Image side of the second lens

S16‧‧‧Side of third lens object

S17‧‧‧The third lens image side

S18‧‧‧Fourth lens side

S19‧‧‧The fourth lens image side

S110‧‧‧Side of fifth lens

S111‧‧‧Image side of fifth lens

S112‧‧‧Filter side

S113‧‧‧ filter image side

Claims (10)

An imaging lens includes: a first lens with positive refractive power, the first lens including a convex surface facing an object side; a second lens with negative refractive power; a third lens with positive refractive power, the third lens including a convex surface The object side; a fourth lens has positive refractive power; and a fifth lens has negative refractive power, the fifth lens includes a concave surface facing an image side; wherein the first lens, the second lens, the third lens, the The fourth lens and the fifth lens are sequentially arranged along the optical axis from the object side to the image side; wherein the imaging lens satisfies the following conditions: 10mm<f ₃ +f ₄ <15mm; where f _{3 is} the first One of the three lenses has an effective focal length, and f _{4 is} one of the fourth lenses. An imaging lens includes: a first lens with positive refractive power, the first lens including a convex surface facing an object side; a second lens with negative refractive power; a third lens with positive refractive power, the third lens including a convex surface The object side; a fourth lens has positive refractive power; and a fifth lens has negative refractive power, the fifth lens includes a concave surface facing an image side; wherein the first lens, the second lens, the third lens, the The fourth lens and the fifth lens are sequentially arranged along the optical axis from the object side to the image side; wherein the imaging lens satisfies the following conditions: 5<(R ₁₁ +R ₁₂ )/(R ₂₁ +R ₂₂ ) <15; where, R ₁₁ is one of the radius of curvature of one of the first lens' object sides, R _{12 is} one of the radius of curvature of one of the image sides of the first lens, and R _{21 is} one of the object sides of the second lens Radius of curvature, R _{22 is a} radius of curvature of one image side of the second lens. The imaging lens as described in item 1 or item 2 of the patent application scope, wherein the imaging lens satisfies the following conditions: -2<f/f ₅ <0;-2.5<f ₅ /f ₁ <0; wherein, f ₁ Is an effective focal length of one of the first lenses, f _{5 is} an effective focal length of the fifth lens, and f is an effective focal length of the imaging lens. The imaging lens as described in item 1 or 2 of the patent application scope, wherein the imaging lens satisfies the following conditions: 0.4<BFL/TTL<0.55; wherein, BFL is an image side to an imaging plane of the fifth lens A pitch on the optical axis, TTL is a pitch on the optical axis from the object side of the first lens to the imaging plane. The imaging lens as described in item 1 or 2 of the patent application scope, wherein the imaging lens satisfies the following conditions: -1<R ₂₁ /R ₂₂ <-0.5; wherein, R ₂₁ is an object side of the second lens one of the radius of curvature, R ₂₂ for the second one of the one side lens curvature radius. The imaging lens as described in item 1 or 2 of the patent application scope, wherein the imaging lens satisfies the following conditions: 0<R ₄₁ /R ₁₁ <2; wherein, R _{11 is} one of the object sides of the first lens Radius of curvature, R _{41 is a} radius of curvature of one of the object sides of the fourth lens. The imaging lens as described in item 1 or item 2 of the patent application scope, wherein the imaging lens satisfies the following conditions: -5<f/f ₂ <-3; where f _{2 is} one of the effective focal lengths of the second lens, f is one of the effective focal lengths of the imaging lens. The imaging lens as described in item 1 or item 2 of the patent application scope, wherein the imaging lens satisfies the following conditions: 10mm<f ₄₅ <15mm; where f _{45 is a combination of} the fourth lens and the fifth lens focal length. The imaging lens as described in item 1 or item 2 of the patent application scope, wherein: the first lens is a meniscus lens and further includes a concave surface facing the image side; the second lens is a biconcave lens including a concave surface The object side and the other concave surface face the image side; the fourth lens is a biconvex lens, including a convex surface toward the object side and the other convex surface toward the image side; and the fifth lens is a biconcave lens, further including a concave surface The object side. The imaging lens as described in item 9 of the patent application scope, wherein: the third lens is a biconvex lens or a meniscus lens, and the imaging lens satisfies the following conditions: -5<(R ₃₁ +R ₃₂ )/(R ₄₁ + R ₄₂ )<2; where R _{31 is a} radius of curvature of an object side of the third lens, R _{32 is a} radius of curvature of an image side of the third lens, and R ₄₁ is an object of the fourth lens A radius of curvature of one of the sides, R _{42 is a} radius of curvature of one of the image sides of the fourth lens.

Images