TWI614520B - Miniature Five-Piece Imaging Lens Module - Google Patents

Abstract

A miniaturized five-piece imaging lens includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens in sequence from the object side to the image side. The first lens has a negative refractive power, the object side is convex and the image side is concave. The second lens has a positive refractive power. The third lens has a negative refractive power, and both the object side and the image side surface are concave. The fourth lens has a positive refractive power, and both the object side and the image side surface are convex. The fifth lens has a negative refractive power, and the object side surface is convex and the image side surface is concave. Among them, the miniaturized five-piece imaging lens also satisfies the following relationship: -9 < (F1 ∙ F4) / F < - 5.5. Thereby, the miniaturized five-piece imaging lens of the present invention can further correct the distortion in addition to the miniaturization and high resolution characteristics.

Description

Miniaturized five-piece imaging lens

The present invention relates to an optical system, and more particularly to a five-piece imaging lens having miniaturization characteristics.

The five-piece imaging lens is a common structure in optical systems. Such lenses were originally manufactured with global glass lenses, and have the disadvantage of not effectively reducing the size of the lens. At present, aspherical lenses have been widely used in such lenses, and aspherical lenses have been widely used in such lenses, which contribute to reducing the size of the lens, and it is desired to correct system aberrations to achieve small size and high resolution. The effect, and how to achieve these characteristics, is worthy of consideration in this field.

SUMMARY OF THE INVENTION A primary object of the present invention is to provide a five-piece imaging lens having miniaturization and high resolution.

In order to achieve the above and other objects, the present invention provides a miniaturized five-piece imaging lens that includes a first lens, a second lens, a third lens, a fourth lens, and a second from the object side to the image side. The fifth lens. The first lens has a negative refractive power, the object side is convex and the image side is concave. The second lens has a positive refractive power. The third lens has a negative refractive power, and both the object side and the image side surface are concave. The fourth lens has a positive refractive power, and both the object side and the image side surface are convex. The fifth lens has a negative refractive power, and the object side surface is convex and the image side surface is concave. Among them, the miniaturized five-piece imaging lens also satisfies the following relationship: -9<(F1∙F4)/F<-5.5; wherein F1 is the focal length value of the first lens, and F4 is the focal length value of the fourth lens, F is the system focal length value of the miniaturized five-piece imaging lens. Thereby, in addition to the miniaturization and high resolution characteristics, the distortion can be further corrected.

In order to achieve the above and other objects, the present invention also provides a miniaturized five-piece imaging lens that sequentially includes a first lens, a second lens, a third lens, and a fourth lens from the object side to the image side. A fifth lens. The first lens has a negative refractive power, and the radius of curvature of the object side surface is a positive value, and the radius of curvature of the object side surface is larger than the radius of curvature of the image side surface. The second lens has a positive refractive power, and the product of the radius of curvature of the object side surface and the radius of curvature of the image side surface is a negative value. The third lens has a negative refractive power, and the radius of curvature of the object side surface is smaller than the radius of curvature of the image side surface, and the radius of curvature of the object side surface is a negative value. The fourth lens has a positive refractive power, and a radius of curvature of the object side surface is larger than a curvature radius of the image side surface, and a curvature radius of the image side surface thereof is a negative value. The fifth lens has a negative refractive power, and the radius of curvature of the object side surface is a positive value, and the radius of curvature of the object side surface is larger than the radius of curvature of the image side surface. Among them, the miniaturized five-piece imaging lens also satisfies the following relationship: -5.7 ≤ (F3 ∙ F4) / F ≤ -4; wherein F3 is the focal length value of the third lens, and F4 is the focal length value of the fourth lens, F is the system focal length value of the miniaturized five-piece imaging lens. Thereby, in addition to the miniaturization and high resolution characteristics, the distortion can be further corrected.

In the above-described miniaturized five-piece imaging lens, the object side surface and the image side surface of the second lens may be convex surfaces.

In the foregoing miniaturized five-piece imaging lens, an aperture may be further included between the second and third lenses.

The aforementioned miniaturized five-piece imaging lens can further satisfy the following relationship: 1.8 ≤ R1/F ≤ 3; wherein R1 is the radius of curvature of the side of the first lens object, thereby correcting the aberration that may be generated by the first lens.

The aforementioned miniaturized five-piece imaging lens can satisfy the following relationship: -5.7 ≤ (F3 ∙ F4) / F ≤ -4; wherein F3 is the focal length value of the third lens, thereby making the system have lower manufacturing sensitivity degree.

The aforementioned miniaturized five-piece imaging lens can satisfy the following relationship: 5.8 ≤ (F1 ∙ F2) / F3 ≤ 8.5; wherein F2 is the focal length value of the second lens, and F3 is the focal length value of the third lens, thereby Make the system have lower aberrations.

The aforementioned miniaturized five-piece imaging lens can satisfy the following relationship: 2.5 ≤ vd1 - vd2 ≤ 6.5; wherein vd1 is the dispersion coefficient of the first lens, and vd2 is the dispersion coefficient of the second lens, thereby correcting the chromatic aberration of the system.

In the miniaturized five-piece imaging lens, the first and second lenses may be glass lenses and both sides are spherical, and the third to fifth lenses may be plastic lenses and both sides are aspherical.

The aforementioned miniaturized five-piece imaging lens can satisfy the following relationship: 0.55<R2/F<0.65, 0.9<R3/F<1.25, -1.5<R4/F<-1.2, -5.2<R5/F<-1.8 , 1<R6/F<1.7, 1.4<R7/F<1.95, -0.5<R8/F<-0.4, 0.5<R9/F<0.7, 0.2<R10/F<0.4, -0.75<F/F1< -0.5, 0.8<F/F2<1.05, -0.9<F/F3<-0.6, 1.2<F/F4<1.45, -0.9<F/F5<-0.4, 2.4<ALT/Gaa<4; where R2 is a radius of curvature of the side surface of the first lens image, R3 is a radius of curvature of a side surface of the second lens object, R4 is a radius of curvature of a side surface of the second lens image, R5 is a radius of curvature of a side surface of the third lens object, and R6 is the first radius The radius of curvature of the side surface of the three lens image, R7 is the radius of curvature of the side surface of the fourth lens object, R8 is the radius of curvature of the side surface of the fourth lens image, R9 is the radius of curvature of the side surface of the fifth lens object, and R10 is the fifth lens. Like the radius of curvature of the side, F2 is the focal length value of the second lens, F3 is the focal length value of the third lens, F5 is the focal length value of the fifth lens, and ALT is the first to fifth lenses on an optical axis. The sum of the thicknesses, Gaa is the first To the sum of the fifth lens on the optical axis of the gap length. Thereby, the miniaturized five-piece imaging lens has the characteristics of miniaturization and high resolution.

Please refer to FIG. 1 , which is a first embodiment of the present invention. The miniaturized five-piece imaging lens (hereinafter referred to as a five-piece lens) is sequentially aligned from the object side A to the image side B on the optical axis L. The invention includes a first lens 10, a second lens 20, a diaphragm ST, a third lens 30, a fourth lens 40 and a fifth lens 50, and is provided with a CCD, CMOS or other photosensitive element on the image side B ( Not shown, a flat lens 60 such as a filter and/or a cover glass may be disposed between the photosensitive element and the fifth lens 50. The number of the flat lenses 60 may be increased or decreased or not set as needed.

In this embodiment, the first lens 10 has a negative refractive power, the object side surface is convex and the image side surface is concave, and the curvature radius of the object side surface is larger than the curvature radius of the image side surface, and the object side surface of the first lens 10 made of glass and The side of the image can be spherical, thereby increasing the viewing angle of the system. In this paper, when the surface center of a curved surface is closer to the image side than the surface itself, the curvature radius of the surface is positive; otherwise, when the surface center of a curved surface is closer to the object side than the surface itself, the surface is The radius of curvature is negative.

The second lens 20 has a positive refractive power, and the object side surface and the image side surface are both convex surfaces. At this time, the product of the curvature radius of the object side surface and the curvature radius of the image side surface is a negative value, and the object side surface of the second lens 20 made of glass and The sides can be spherical. Thereby, the second lens 20 can provide the main refractive power of the system.

The third lens 30 has a negative refractive power, and the object side surface and the image side surface are both concave surfaces, that is, the curvature radius of the object side surface is smaller than the curvature radius of the image side surface, and the object side surface and the image side surface of the third lens 30 made of plastic may be Aspherical surface, thereby effectively reducing lateral chromatic aberration.

The fourth lens 40 has a positive refractive power, and the object side surface and the image side surface are convex surfaces and are a lenticular lens, that is, the radius of curvature of the object side surface is positive and larger than the curvature radius of the image side surface, and the fourth lens made of plastic is used. The object side and the image side of 40 may be aspherical. Thereby, the fourth lens 40 can be used to reduce system astigmatism.

The fifth lens 50 has a negative refractive power, and the object side surface is convex and the image side surface is concave, that is, the curvature radius of the object side surface is larger than the curvature radius of the image side surface, and the object side surface and the image side surface of the fifth lens 50 made of plastic can be It is an aspherical surface, and the fifth lens 50 has at least one inflection point in the object side and the image side surface, thereby effectively reducing the system field curvature.

The design parameters of the five-piece lens of this embodiment are as shown in Table 1 below:

Table I

In this embodiment, the object side surface and the image side surface of the third to fifth lenses 30, 40, 50 are aspherical surfaces, and the surface shape thereof satisfies the following aspherical formula:

Where c=1/r, r is the radius of curvature of the surface, h is the height of the light on the surface, k is the cone coefficient, B is the fourth-order coefficient, C is the sixth-order coefficient, and D is the eighth-order coefficient, E For the tenth order coefficient, F is the twelfth order coefficient and G is the fourteenth order coefficient. The parameters of each aspheric surface of the first embodiment are as shown in Table 2 below:

Table II

Based on the foregoing design, the system focal length value F of the present embodiment is 5.015 mm, the system length is 16.5 mm, the first lens focal length value is -9.06 mm, the second lens focal length value is -5.81 mm, and the third lens focal length value is -7.99. Mm, the focal length of the fourth lens is 3.55 mm, and the focal length of the fifth lens is -6.31 mm.

At this time, the values of the relationship of the five-piece lens are as shown in Table 3 below:

Table 3

In this way, the five-piece lens has the characteristics of miniaturization, high resolution and small distortion. The field curvature and distortion map are as shown in Fig. 1A. The maximum field curvature value does not exceed 0.6 mm, and the maximum distortion is about ± 1% or less, the lateral chromatic aberration diagram of different image heights is as shown in Fig. 1B, and it can be seen that there are good chromatic aberration performances at different image heights.

Please refer to FIG. 2 , which is a second embodiment of the present invention. The lens configuration is similar to that of the first embodiment. The design parameters of the five-piece lens of this embodiment are as shown in Table 4 below:

Table 4

In this embodiment, the object side surface and the image side surface of the third to fifth lenses 30, 40, 50 are all aspherical surfaces, and the surface shape thereof satisfies the above aspherical surface formula, and the parameters of the aspheric surfaces of the second embodiment are as follows: Shown as follows:

Table 5

Based on the foregoing design, the focal length value F of the present embodiment is 5.05 mm, the length of the system is 16.5 mm, the focal length of the first lens is -0.89 mm, the focal length of the second lens is 5.86 mm, and the focal length of the third lens is -7.63 mm. The fourth lens focal length value is 3.67 mm, and the fifth lens focal length value is -6.76 mm.

At this time, the values of the relationship of the five-piece lens are as shown in Table 6 below:

Table 6

In this way, the five-piece lens has the characteristics of miniaturization, high resolution and small distortion. The field curvature and distortion map are as shown in Fig. 2A. The maximum field curvature value does not exceed 0.6 mm, and the maximum distortion is about ± 1% or less, the lateral chromatic aberration diagram of different image heights is as shown in Fig. 2B, and it can be seen that there are good chromatic aberration performances at different image heights.

Please refer to FIG. 3, which is a third embodiment of the present invention. The lens configuration is similar to that of the first embodiment. The design parameters of the five-piece lens of this embodiment are as shown in Table 7 below:

Table 7

In this embodiment, the object side surface and the image side surface of the third to fifth lenses 30, 40, 50 are all aspherical surfaces, and the surface shape thereof satisfies the above aspherical surface formula, and the parameters of the aspheric surfaces of the third embodiment are as follows. Shown as follows:

Table eight

Based on the foregoing design, the system focal length value F of the present embodiment is 5.03 mm, the system length is 16.77 mm, the first lens focal length value is -8.31 mm, the second lens focal length value is 5.39 mm, and the third lens focal length value is -6.54 mm. The fourth lens has a focal length of 4 mm and the fifth lens has a focal length of -8.43 mm.

At this time, the values of the relationship of the five-piece lens are as shown in Table 9 below:

Table 9

In this way, the five-piece lens has the characteristics of miniaturization, high resolution and small distortion. The field curvature and distortion map are as shown in Fig. 3A. The maximum field curvature value does not exceed 0.4 mm, and the maximum distortion is about ± 1.5% or less, the lateral chromatic aberration diagram of different image heights, as shown in Fig. 3B, shows good chromatic aberration performance at different image heights.

Please refer to FIG. 4, which is a fourth embodiment of the present invention. The lens configuration is similar to that of the first embodiment. The design parameters of the five-piece lens of this embodiment are as shown in Table 10 below:

Table ten

In this embodiment, the object side surface and the image side surface of the third to fifth lenses 30, 40, 50 are all aspherical surfaces, and the surface shape thereof satisfies the above aspherical surface formula, and the parameters of the aspheric surfaces of the fourth embodiment are as follows: One:

Table XI

Based on the foregoing design, the system focal length value F of the present embodiment is 5.13 mm, the system length is 17.17 mm, the first lens focal length value is -1.06 mm, the second lens focal length value is 5.77 mm, and the third lens focal length value is -6.91 mm. The fourth lens has a focal length of 4 mm and the fifth lens has a focal length of -8.34 mm.

At this time, the values of the relationship of the five-piece lens are as shown in Table 12 below:

Table 12

As a result, the five-piece lens has the characteristics of miniaturization, high resolution and small distortion. The field curvature and distortion map are as shown in Fig. 4A. The maximum field curvature value does not exceed 0.8 mm, and the maximum distortion is about ± 1.5% or less, the lateral chromatic aberration diagram of different image heights is as shown in Fig. 4B, and it can be seen that there are good chromatic aberration performances at different image heights.

Please refer to FIG. 5, which is a fifth embodiment of the present invention. The lens configuration is similar to that of the first embodiment. The design parameters of the five-piece lens of this embodiment are as shown in Table 13 below:

Table thirteen

In this embodiment, the object side surface and the image side surface of the third to fifth lenses 30, 40, 50 are all aspherical surfaces, and the surface shape thereof satisfies the above aspherical surface formula, and the parameters of the aspheric surfaces of the fifth embodiment are as follows: Four:

Table fourteen

Based on the foregoing design, the system focal length value F of the embodiment is 5.11 mm, the system length is 16.85 mm, the first lens focal length value is -7.32 mm, the second lens focal length value is 5.18 mm, and the third lens focal length value is -6.39 mm. The fourth lens focal length value is 4.13 mm, and the fifth lens focal length value is -10.08 mm.

At this time, the values of the relationship of the five-piece lens are as shown in Table 15 below:

In this way, the five-piece lens has the characteristics of miniaturization, high resolution and small distortion, and its field curvature and distortion map are as shown in Fig. 5A, the maximum field curvature value does not exceed 0.6 mm, and the maximum distortion is At about ±1.5% or less, the lateral chromatic aberration diagrams at different image heights are as shown in Fig. 5B, and it is seen that there is good chromatic aberration performance at different image heights.

10‧‧‧ first lens

20‧‧‧second lens

30‧‧‧ third lens

40‧‧‧Fourth lens

50‧‧‧ fifth lens

60‧‧‧ flat lenses

A‧‧‧ object side

B‧‧‧ image side

ST‧‧‧ aperture

L‧‧‧ optical axis

Figure 1 is a schematic view of a first embodiment of the present invention.

Fig. 1A is a field curvature and distortion diagram of the first embodiment of the present invention.

Fig. 1B is a lateral chromatic aberration diagram at different image heights in the first embodiment of the present invention.

Figure 2 is a schematic view of a second embodiment of the present invention.

Fig. 2A is a field curvature and distortion diagram of the second embodiment of the present invention.

Fig. 2B is a lateral chromatic aberration diagram at different image heights in the second embodiment of the present invention.

Figure 3 is a schematic view of a third embodiment of the present invention.

Fig. 3A is a field curvature and distortion diagram of the third embodiment of the present invention.

Fig. 3B is a lateral chromatic aberration diagram at different image heights in the third embodiment of the present invention.

Figure 4 is a schematic view of a fourth embodiment of the present invention.

Fig. 4A is a field curvature and distortion diagram of a fourth embodiment of the present invention.

Fig. 4B is a lateral chromatic aberration diagram at different image heights in the fourth embodiment of the present invention.

Fig. 5 is a schematic view showing a fifth embodiment of the present invention.

Fig. 5A is a field curvature and distortion diagram of a fifth embodiment of the present invention.

Fig. 5B is a diagram showing lateral chromatic aberration at different image heights in the fifth embodiment of the present invention.

First lens 10 second lens 20 third lens 30 fourth lens 40 fifth lens 50 flat lens 60 object side A image side B aperture ST optical axis L

Claims (9)

A miniaturized five-piece imaging lens includes, in order from the object side to the image side, a first lens having a negative refractive power, a convex side of the object surface and a concave side like the side surface, and a second lens having a positive refractive power; a three-lens lens having a negative refractive power, a concave side of the object side surface and the image side surface; a fourth lens having a positive refractive power, the object side surface and the image side surface being convex surfaces; and a fifth lens having a negative refractive power, the object side being The convex surface and the image side surface are concave surfaces; wherein the miniaturized five-piece imaging lens further satisfies the following relationship: -9<(F1.F4)/F<-5.5; wherein F1 is the focal length value of the first lens, and F4 is The focal length value of the fourth lens, F is the system focal length value of the miniaturized five-piece imaging lens; -5.7 (F3.F4)/F -4; wherein F3 is the focal length value of the third lens. A miniaturized five-piece imaging lens includes, in order from the object side to the image side, a first lens having a negative refractive power, a radius of curvature of the object side surface being positive, and a radius of curvature of the object side surface being larger than a radius of curvature of the image side surface a second lens having a positive refractive power, a product of a radius of curvature of the side of the object and a radius of curvature of the image side being negative; a third lens having a negative refractive power, a radius of curvature of the side of the object being smaller than a radius of curvature of the side of the image, And a radius of curvature of the side of the object is a negative value; a fourth lens having a positive refractive power, a radius of curvature of the side of the object is larger than a radius of curvature of the side of the image, and a radius of curvature of the image side is a negative value; and a fifth lens, With a negative refractive power, the radius of curvature of the object side is positive, and the radius of curvature of the side of the object is larger than the radius of curvature of the side of the image; wherein the miniaturized five-piece imaging lens more satisfies the following relationship: -5.7 (F3.F4)/F -4; wherein F3 is the focal length value of the third lens, F4 is the focal length value of the fourth lens, and F is the system focal length value of the miniaturized five-piece imaging lens. A miniaturized five-piece imaging lens includes, in order from the object side to the image side, a first lens having a negative refractive power, a radius of curvature of the object side surface being positive, and a radius of curvature of the object side surface being larger than a radius of curvature of the image side surface a second lens having a positive refractive power, a product of a radius of curvature of the side of the object and a radius of curvature of the image side being negative; a third lens having a negative refractive power, a radius of curvature of the side of the object being smaller than a radius of curvature of the side of the image, And a radius of curvature of the side of the object is a negative value; a fourth lens having a positive refractive power, a radius of curvature of the side of the object is larger than a radius of curvature of the side of the image, and a radius of curvature of the image side is a negative value; and a fifth lens, With a negative refractive power, the radius of curvature of the object side is positive, and the radius of curvature of the side of the object is larger than the radius of curvature of the side of the image; wherein the miniaturized five-piece imaging lens more satisfies the following relationship: 1.8 R1/F 3; wherein R1 is the radius of curvature of the side of the first lens. A miniaturized five-piece imaging lens includes, in order from the object side to the image side, a first lens having a negative refractive power, a radius of curvature of the object side surface being positive, and a radius of curvature of the object side surface being larger than a radius of curvature of the image side surface a second lens having a positive refractive power, a product of a radius of curvature of the side of the object and a radius of curvature of the image side being negative; a third lens having a negative refractive power, a radius of curvature of the side of the object being smaller than a radius of curvature of the side of the image, And a radius of curvature of the side of the object is a negative value; a fourth lens having a positive refractive power, a radius of curvature of the side of the object is larger than a radius of curvature of the side of the image, and a radius of curvature of the image side is a negative value; and a fifth lens, With a negative refractive power, the radius of curvature of the object side is positive, and the radius of curvature of the side of the object is larger than the radius of curvature of the side of the image; wherein the miniaturized five-piece imaging lens more satisfies the following relationship: 2.5 Vd1-vd2 6.5; wherein vd1 is the dispersion coefficient of the first lens, and vd2 is the dispersion coefficient of the second lens. The miniaturized five-piece imaging lens of claim 1, 2, 3 or 4, wherein the object side and the image side of the second lens are convex. The miniaturized five-piece imaging lens described in claim 3 or 4 satisfies the following relationship: -5.7 (F3.F4)/F -4; wherein F3 is the focal length value of the third lens. The miniaturized five-piece imaging lens described in claim 1, 2, 3 or 4 satisfies the following relationship: 5.8 (F1.F2)/F3 8.5; wherein F1 is a focal length value of the first lens, F2 is a focal length value of the second lens, and F3 is a focal length value of the third lens. The miniaturized five-piece imaging lens of claim 1, 2, 3 or 4, further comprising an aperture between the second and third lenses. The miniaturized five-piece imaging lens according to claim 2, 3 or 4 further satisfies the following relationship: -9 < (F1.F4) / F < -5.5; wherein F1 is the focal length value of the first lens.