Optical imaging lens

Abstract

An optical imaging lens sequentially comprises a first lens, a second lens, a third lens and a fourth lens from an object side to an image side along an optical axis, and each of the first lens, the second lens, the third lens and the fourth lens comprises an object side surface which faces the object side and enables imaging light to pass through and an image side surface which faces the image side and enables the imaging light to pass through. Wherein an optical axis area of the image side surface of the third lens is a concave surface, a circumferential area of the object side surface of the fourth lens is a convex surface, an optical axis area of the image side surface of the fourth lens is a concave surface, a circumferential area of the image side surface of the fourth lens is a convex surface, and the optical imaging lens only comprises the four lenses.

Description

Technical Field

[0001] The invention relates to an optical element, and in particular to an optical imaging lens. Background Art

[0002] The specifications of portable electronic devices are changing with each passing day, and their key components - optical imaging lenses are also becoming more diversified. The main lens of portable electronic devices not only requires a larger aperture and a shorter system length, but also pursues higher pixels and higher resolution. In recent years, optical imaging lenses have continued to evolve and are used in a wider range of applications. In addition to requiring the lens to be thin, light and short, the design of a small aperture value (Fno) is conducive to increasing the light flux. How to design an optical imaging lens that is both thin, light, short, and has a small aperture value and good imaging quality has become a challenge that needs to be solved. Summary of the invention

[0003] The present invention provides an optical imaging lens, which is a lens having a small aperture value and excellent imaging quality.

[0004] The present invention provides an optical imaging lens, which includes a first lens, a second lens, a third lens and a fourth lens in sequence along an optical axis from an object side to an image side, and the first lens to the fourth lens each include an object side surface facing the object side and allowing an imaging light to pass through, and an image side surface facing the image side and allowing the imaging light to pass through. An optical axis region of the image side surface of the third lens is a concave surface. A circumferential region of the object side surface of the fourth lens is a convex surface. An optical axis region of the image side surface of the fourth lens is a concave surface. A circumferential region of the image side surface of the fourth lens is a convex surface. Among them, the optical imaging lens has only the above-mentioned four lenses and satisfies the following conditional formula: EPD / AAG≥2.500, wherein EPD is the entrance pupil diameter of the optical imaging lens, and AAG is the sum of three air gaps on the optical axis of the first lens to the fourth lens.

[0005] The present invention further provides an optical imaging lens, which includes a first lens, a second lens, a third lens and a fourth lens in sequence along an optical axis from an object side to an image side, and each of the first lens to the fourth lens includes an object side surface facing the object side and allowing an imaging light to pass through, and an image side surface facing the image side and allowing the imaging light to pass through. A circumferential area of ​​the object side surface of the third lens is a convex surface. An optical axis area of ​​the image side surface of the third lens is a concave surface. A circumferential area of ​​the object side surface of the fourth lens is a convex surface. An optical axis area of ​​the image side surface of the fourth lens is a concave surface. A circumferential area of ​​the image side surface of the fourth lens is a convex surface. Among them, the optical imaging lens has only the above four lenses and satisfies the following conditional formula: EPD / (AAG+BFL)≥1.000, wherein EPD is the entrance pupil diameter of the optical imaging lens, AAG is the sum of three air gaps on the optical axis between the first lens to the fourth lens, and BFL is the distance from the image side surface of the fourth lens to an imaging surface on the optical axis.

[0006] The present invention further provides an optical imaging lens, which includes a first lens, a second lens, a third lens and a fourth lens in sequence along an optical axis from an object side to an image side, and the first lens to the fourth lens each include an object side surface facing the object side and allowing an imaging light to pass through, and an image side surface facing the image side and allowing the imaging light to pass through. A circumferential area on the object side surface of the third lens is a convex surface. An optical axis area on the image side surface of the fourth lens is a concave surface. A circumferential area on the image side surface of the fourth lens is a convex surface. Among them, the optical imaging lens has only the above four lenses and satisfies the following conditional formula: EPD / ImgH≥2.600, wherein EPD is the entrance pupil diameter of the optical imaging lens, and ImgH is the maximum image height of the optical imaging lens.

[0007] Based on the above, the beneficial effect of the optical imaging lens of the embodiment of the present invention is: providing a lens with a small aperture value and excellent imaging quality, which can be applied to the blue light segment with a wavelength of 400 to 500nm, has a significant improvement effect on field curvature, distortion or longitudinal aberration, and reflects good MTF resolution and imaging quality.

[0008] In order to make the above features and advantages of the present invention more clearly understood, embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram illustrating the surface structure of a lens.

[0010] Figure 2 It is a schematic diagram illustrating the concave-convex structure of a lens surface and the intersection of light rays.

[0011] Figure 3 is a schematic diagram illustrating the surface structure of a lens of Example 1.

[0012] Figure 4 is a schematic diagram illustrating the surface structure of a lens of Example 2.

[0013] Figure 5 is a schematic diagram illustrating the surface structure of a lens of Example 3.

[0014] Figure 6 It is a schematic diagram of an optical imaging lens according to a first embodiment of the present invention.

[0015] 7A to 7D Graphs showing longitudinal spherical aberration and various aberrations of the optical imaging lens of the first embodiment.

[0016] Figure 8 Detailed optical data of the optical imaging lens according to the first embodiment of the present invention are shown.

[0017] Fig. 9 The aspherical parameters of the optical imaging lens according to the first embodiment of the present invention are shown.

[0018] Fig.10 FIG. 4 is a schematic diagram of an optical imaging lens according to a second embodiment of the present invention.

[0019] FIG. 11A to FIG. 11D Graphs showing longitudinal spherical aberration and various aberrations of the optical imaging lens of the second embodiment.

[0020] Fig.12 Detailed optical data of the optical imaging lens according to the second embodiment of the present invention are shown.

[0021] Fig.13 The aspherical parameters of the optical imaging lens according to the second embodiment of the present invention are shown.

[0022] Fig.14 FIG. 4 is a schematic diagram of an optical imaging lens according to a third embodiment of the present invention.

[0023] FIG. 15A to FIG. 15D Graphs showing longitudinal spherical aberration and various aberrations of the optical imaging lens of the third embodiment.

[0024] Fig.16 Detailed optical data of the optical imaging lens according to the third embodiment of the present invention are shown.

[0025] Fig.17 The aspherical parameters of the optical imaging lens according to the third embodiment of the present invention are shown.

[0026] Fig.18 FIG. 4 is a schematic diagram of an optical imaging lens according to a fourth embodiment of the present invention.

[0027] FIG. 19A to FIG. 19D Graphs showing longitudinal spherical aberration and various aberrations of the optical imaging lens of the fourth embodiment.

[0028] Fig. 20 Detailed optical data of the optical imaging lens according to the fourth embodiment of the present invention are shown.

[0029] Fig.21 The aspherical parameters of the optical imaging lens according to the fourth embodiment of the present invention are shown.

[0030] Fig. 22 FIG. 4 is a schematic diagram of an optical imaging lens according to a fifth embodiment of the present invention.

[0031] FIG. 23A to FIG. 23D Graphs showing longitudinal spherical aberration and various aberrations of the optical imaging lens of the fifth embodiment.

[0032] Fig.24 Detailed optical data of the optical imaging lens according to the fifth embodiment of the present invention are shown.

[0033] Fig.25 FIG. 5 shows aspherical parameters of the optical imaging lens according to the fifth embodiment of the present invention.

[0034] Fig.26 FIG. 4 is a schematic diagram of an optical imaging lens according to a sixth embodiment of the present invention.

[0035] FIG. 27A to FIG. 27D Graphs showing longitudinal spherical aberration and various aberrations of the optical imaging lens of the sixth embodiment.

[0036] Fig.28 Detailed optical data of the optical imaging lens according to the sixth embodiment of the present invention are shown.

[0037] Fig.29 The aspherical parameters of the optical imaging lens according to the sixth embodiment of the present invention are shown.

[0038] Fig.30 FIG. 4 is a schematic diagram of an optical imaging lens according to a seventh embodiment of the present invention.

[0039] FIG. 31A to FIG. 31D Graphs showing longitudinal spherical aberration and various aberrations of the optical imaging lens of the seventh embodiment.

[0040] Fig.32 Detailed optical data of the optical imaging lens according to the seventh embodiment of the present invention are shown.

[0041] Fig.33 FIG. 5 shows aspherical parameters of the optical imaging lens according to the seventh embodiment of the present invention.

[0042] Fig.34 is a schematic diagram of an optical imaging lens according to an eighth embodiment of the present invention.

[0043] FIG. 35A to FIG. 35DGraphs showing longitudinal spherical aberration and various aberrations of the optical imaging lens of the eighth embodiment.

[0044] Fig.36 Detailed optical data of the optical imaging lens according to the eighth embodiment of the present invention are shown.

[0045] Fig.37 The aspherical parameters of the optical imaging lens according to the eighth embodiment of the present invention are shown.

[0046] Fig.38 is a schematic diagram of an optical imaging lens according to a ninth embodiment of the present invention.

[0047] FIG. 39A to FIG. 39D Graphs showing longitudinal spherical aberration and various aberrations of the optical imaging lens of the ninth embodiment.

[0048] Fig.40 Detailed optical data of the optical imaging lens according to the ninth embodiment of the present invention are shown.

[0049] Fig.41 FIG. 4 shows aspherical parameters of the optical imaging lens according to the ninth embodiment of the present invention.

[0050] Fig.42 as well as Fig.43 The important parameters and the values ​​of their relationship expressions of the optical imaging lenses of the first to fifth embodiments of the present invention are shown.

[0051] Fig.44 as well as Fig.45 The important parameters and the values ​​of their relationship expressions of the optical imaging lenses of the sixth to ninth embodiments of the present invention are shown.

[0052] Description of reference numerals:

[0053] 0: aperture; 1: first lens; 2: second lens; 3: third lens; 4: fourth lens;

[0054] 8: filter; 9: protective cover;

[0055] 10: Optical imaging lens;

[0056] 15, 25, 35, 45, 85, 95, 110, 410, 510: side view of the object;

[0057] 16, 26, 36, 46, 86, 96, 120, 320: image side; 99: imaging surface;

[0058] 100, 200, 300, 400, 500: lenses; 130: assembly part;

[0059] 151, 161, 251, 261, 351, 361, 451, 461, Z 1: optical axis area;

[0060] 153, 163, 253, 263, 353, 363, 453, 463, Z2: circumferential area;

[0061] 211, 212: parallel light rays;

[0062] A1: object side; A2: image side;

[0063] CP: center point; CP 1: first center point; CP2: second center point; EL: extension line; I: optical axis;

[0064] Lc: principal ray; Lm: marginal ray; M, R: intersection point; OB: optical boundary;

[0065] TP 1: first transition point; TP2: second transition point; Z3: relay zone. DETAILED DESCRIPTION

[0066] The terms "optical axis region", "circumferential region", "concave surface" and "convex surface" used in this specification and the claims should be interpreted based on the definitions listed in this specification.

[0067] The optical system of this specification includes at least one lens, which receives imaging light from the incident optical system that is parallel to the optical axis and within a half-field of view (HFOV) angle relative to the optical axis. The imaging light forms an image on the imaging plane through the optical system. The phrase "a lens has a positive refractive power (or a negative refractive power)" refers to the paraxial refractive power of the lens calculated by Gaussian optical theory being positive (or negative). The "object side (or image side) of the lens" is defined as a specific range where the imaging light passes through the lens surface. The imaging light includes at least two types of light: the chief ray (chief ray) Lc and the marginal ray (marginal ray) Lm (such as Figure 1 The object side (or image side) of the lens can be divided into different regions according to different positions, including an optical axis region, a circumferential region, or one or more intermediate regions in some embodiments. The description of these regions will be described in detail below.

[0068] Figure 1 is a radial cross-sectional view of the lens 100. Two reference points on the surface of the lens 100 are defined: a center point and a transition point. The center point of the lens surface is an intersection point of the surface and the optical axis I. Figure 1As shown in the example, the first center point CP1 is located on the object side 110 of the lens 100, and the second center point CP2 is located on the image side 120 of the lens 100. A conversion point is a point on the lens surface, and the tangent of the point is perpendicular to the optical axis I. The optical boundary OB of the lens surface is defined as the point where the radially outermost edge ray Lm passing through the lens surface intersects the lens surface. All conversion points are located between the optical axis I and the optical boundary OB of the lens surface. In addition, the surface of the lens 100 may have no conversion points or at least one conversion point. If a single lens surface has multiple conversion points, the conversion points are named in sequence from the first conversion point in the radial outward direction. For example, the first conversion point TP1 (closest to the optical axis I), the second conversion point TP2 (closest to the optical axis I), and the second conversion point TP2 (closest to the optical axis I). Figure 4 as shown) and the Nth conversion point (farthest from the optical axis I).

[0069] When the lens surface has at least one transition point, the range from the center point to the first transition point TP 1 is defined as the optical axis area, wherein the optical axis area includes the center point. The area radially outward from the transition point farthest from the optical axis I (the Nth transition point) to the optical boundary OB is defined as the circumferential area. In some embodiments, a relay area between the optical axis area and the circumferential area may be further included, and the number of relay areas depends on the number of transition points. When the lens surface does not have a transition point, 0% to 50% of the distance from the optical axis I to the optical boundary OB of the lens surface is defined as the optical axis area, and 50% to 100% of the distance from the optical axis I to the optical boundary OB of the lens surface is defined as the circumferential area.

[0070] When a light ray parallel to the optical axis I passes through an area, if the light ray is deflected toward the optical axis I and the intersection with the optical axis I is located at the image side A2 of the lens, then the area is convex. When a light ray parallel to the optical axis I passes through an area, if the extension line of the light ray intersects with the optical axis I at the object side A1 of the lens, then the area is concave.

[0071] In addition, see Figure 1 The lens 100 may further include an assembly portion 130 extending radially outward from the optical boundary OB. The assembly portion 130 is generally used for assembling the lens 100 to a corresponding element (not shown) of the optical system. The imaging light does not reach the assembly portion 130. The structure and shape of the assembly portion 130 are merely examples for illustrating the present invention and are not intended to limit the scope of the present invention. The assembly portion 130 of the lens discussed below may be partially or completely omitted in the drawings.

[0072] See also Figure 2 , define the area between the center point CP and the first transition point TP1 as the optical axis area Z1. Define the area between the first transition point TP1 and the optical boundary OB of the lens surface as the circumferential area Z2. Figure 2As shown, after passing through the optical axis region Z1, the parallel light 211 intersects with the optical axis I at the image side A2 of the lens 200, that is, the focus of the parallel light 211 passing through the optical axis region Z1 is located at point R on the image side A2 of the lens 200. Since the light intersects with the optical axis I at the image side A2 of the lens 200, the optical axis region Z1 is a convex surface. On the contrary, the parallel light 212 diverges after passing through the circumferential region Z2. Figure 2 As shown, the extended line EL of the parallel light 212 after passing through the circumferential area Z2 intersects with the optical axis I at the object side A1 of the lens 200, that is, the focus of the parallel light 212 passing through the circumferential area Z2 is located at point M on the object side A1 of the lens 200. Since the extended line EL of the light intersects with the optical axis I at the object side A1 of the lens 200, the circumferential area Z2 is a concave surface. Figure 2 In the lens 200 shown, the first transition point TP 1 is the boundary between the optical axis area and the circumference area, that is, the first transition point TP 1 is the boundary point where the convex surface turns into the concave surface.

[0073] On the other hand, the surface convexity of the optical axis area can also be determined according to the judgment method of the general knowledgeable person in the field, that is, the convexity of the surface shape of the optical axis area of ​​the lens can be determined by the positive and negative signs of the curvature radius of the paraxial axis (abbreviated as R value). R value can be commonly used in optical design software, such as Zemax or CodeV. R value is also commonly found in the lens data sheet of optical design software. For the object side, when the R value is positive, the optical axis area of ​​the object side is determined to be convex; when the R value is negative, the optical axis area of ​​the object side is determined to be concave. On the contrary, for the image side, when the R value is positive, the optical axis area of ​​the image side is determined to be concave; when the R value is negative, the optical axis area of ​​the image side is determined to be convex. The result of this method is consistent with the result of the above-mentioned determination method by the intersection of the light ray / light extension line and the optical axis. The determination method of the intersection of the light ray / light extension line and the optical axis is to determine the surface convexity by the focus of a light ray parallel to the optical axis located on the object side or image side of the lens. The terms “a region is convex (or concave)”, “a region is convex (or concave)” or “a convex (or concave) region” described in this specification can be used interchangeably.

[0074] Figures 3 to 5 Examples are provided for determining the surface shape and area boundaries of lens areas in various situations, including the aforementioned optical axis area, circumferential area, and relay area.

[0075] Figure 3 is a radial cross-sectional view of the lens 300. Figure 3 , the image side surface 320 of the lens 300 has only one transition point TP1 within the optical boundary OB. The optical axis area Z1 and the circumferential area Z2 of the image side surface 320 of the lens 300 are as follows: Figure 3 The R value of the image-side surface 320 is positive (ie, R>0), and therefore, the optical axis region Z1 is a concave surface.

[0076] Generally speaking, the shapes of the areas bounded by the conversion point are opposite to those of the adjacent areas. Therefore, the conversion point can be used to define the transition of the surface shape, that is, from concave to convex or from convex to concave. Figure 3 In the figure, since the optical axis area Z1 is a concave surface, the surface shape changes at the transition point TP1, so the circumferential area Z2 is a convex surface.

[0077] Figure 4 is a radial cross-sectional view of the lens 400. Figure 4 , there is a first transition point TP1 and a second transition point TP2 on the object side surface 410 of the lens 400. The area between the optical axis I and the first transition point TP1 is defined as an optical axis region Z1 of the object side surface 410. The R value of the object side surface 410 is positive (ie, R>0), and therefore, the optical axis region Z1 is a convex surface.

[0078] The area between the second transition point TP2 and the optical boundary OB of the object side surface 410 of the lens 400 is defined as a circumferential area Z2, and the circumferential area Z2 of the object side surface 410 is also a convex surface. In addition, the area between the first transition point TP1 and the second transition point TP2 is defined as a relay area Z3, and the relay area Z3 of the object side surface 410 is a concave surface. Figure 4 The object-side surface 410 includes, radially outward from the optical axis I, an optical axis region Z1 between the optical axis I and the first turning point TP1, a relay region Z3 between the first turning point TP1 and the second turning point TP2, and a circumferential region Z2 between the second turning point TP2 and the optical boundary OB of the object-side surface 410 of the lens 400. Since the optical axis region Z1 is a convex surface, the surface shape changes from the first turning point TP1 to a concave surface, so the relay region Z3 is a concave surface, and the surface shape changes from the second turning point TP2 to a convex surface, so the circumferential region Z2 is a convex surface.

[0079] Figure 5 is a radial cross-sectional view of the lens 500. The object side surface 510 of the lens 500 has no transition point. For a lens surface without a transition point, such as the object side surface 510 of the lens 500, 0% to 50% of the distance from the optical axis I to the optical boundary OB of the lens surface is defined as the optical axis area, and 50% to 100% of the distance from the optical axis I to the optical boundary OB of the lens surface is defined as the circumferential area. Figure 5 The lens 500 shown in the figure defines the optical axis region Z1 of the object side surface 510 as 50% of the distance from the optical axis I to the optical boundary OB of the lens 500 surface. The R value of the object side surface 510 is positive (i.e., R>0), so the optical axis region Z1 is a convex surface. Since the object side surface 510 of the lens 500 has no transition point, the circumferential region Z2 of the object side surface 510 is also a convex surface. The lens 500 may further have an assembly portion (not shown) extending radially outward from the circumferential region Z2.

[0080] Figure 6 It is a schematic diagram of an optical imaging lens according to a first embodiment of the present invention. 7A to 7D The longitudinal spherical aberration and various aberration diagrams of the optical imaging lens of the first embodiment. Figure 6 The optical imaging lens 10 of the first embodiment of the present invention includes an aperture 0, a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a filter 8 and a protective cover 9 in order from the object side A1 to the image side A2 along an optical axis I of the optical imaging lens 10. When light emitted by an object to be photographed enters the optical imaging lens 10 and passes through the aperture 0, the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the filter 8 and the protective cover 9, an image is formed on an imaging plane 99. It should be noted that the object side A1 is the side facing the object to be photographed, and the image side A2 is the side facing the imaging plane 99. In this embodiment, the filter 8 is a band pass filter, and the protective cover 9 is a glass transparent sheet. The bandpass filter is designed to have an average transmittance of light in the 360-380nm band of ≦3%; an average transmittance of light in the 400-500nm band of ≧95%; and an average transmittance of light in the 550-1150nm band of ≦3%.

[0081] In this embodiment, the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the filter 8 and the protective cover 9 of the optical imaging lens 10 each have an object-side surface 15, 25, 35, 45, 85, 95 facing the object side A1 and through which imaging light passes, and an image-side surface 16, 26, 36, 46, 86, 96 facing the image side A2 and through which imaging light passes. In this embodiment, the aperture O is disposed on a side of the first lens 1 facing the object side A1.

[0082] The first lens 1 has a positive refractive power. The optical axis region 151 of the object side surface 15 of the first lens 1 is a convex surface, and the circumferential region 153 thereof is a convex surface. The optical axis region 161 of the image side surface 16 of the first lens 1 is a concave surface, and the circumferential region 163 thereof is a convex surface. In the present embodiment, both the object side surface 15 and the image side surface 16 of the first lens 1 are aspheric surfaces, but the present invention is not limited thereto.

[0083] The second lens 2 has a negative refractive power. The optical axis region 251 of the object side surface 25 of the second lens 2 is a convex surface, and the circumferential region 253 thereof is a convex surface. The optical axis region 261 of the image side surface 26 of the second lens 2 is a concave surface, and the circumferential region 263 thereof is a concave surface. In the present embodiment, both the object side surface 25 and the image side surface 26 of the second lens 2 are aspherical surfaces, but the present invention is not limited thereto.

[0084] The third lens 3 has a negative refractive power. The optical axis region 351 of the object side surface 35 of the third lens 3 is a convex surface, and the circumferential region 353 thereof is a convex surface. The optical axis region 361 of the image side surface 36 of the third lens 3 is a concave surface, and the circumferential region 363 thereof is a concave surface. In the present embodiment, both the object side surface 35 and the image side surface 36 of the third lens 3 are aspherical surfaces, but the present invention is not limited thereto.

[0085] The fourth lens 4 has a positive refractive power. The optical axis region 451 of the object side surface 45 of the fourth lens 4 is a convex surface, and the circumferential region 453 thereof is a convex surface. The optical axis region 461 of the image side surface 46 of the fourth lens 4 is a concave surface, and the circumferential region 463 thereof is a convex surface. In the present embodiment, the object side surface 45 and the image side surface 46 of the fourth lens 4 are both aspherical surfaces, but the present invention is not limited thereto.

[0086] In this embodiment, the optical imaging lens system 10 only includes the four lenses mentioned above.

[0087] Other detailed optical data of the first embodiment are as follows Figure 8 As shown, the effective focal length (EFL) of the optical imaging lens 10 of the first embodiment is 1.317 millimeters (mm), the half field of view (HFOV) is 12.274 degrees, the system length is 1.868 millimeters, the aperture value (F-number, Fno) is 1.260, and the image height is 0.276 millimeters, wherein the system length refers to the distance from the object side surface 15 of the first lens 1 to the imaging surface 99 on the optical axis I. Among them, the material parameters of the lens disclosed in the optical parameter table of the embodiment are in the format of nd refractive index and Vd Abbe number of the international glass code, so that those skilled in the art can know the specific material implementation. Among them, the nd refractive index is the refractive index of the material at the d helium yellow line 587.56 nanometers, and the Vd Abbe number is calculated based on the refractive index of the material at the d, F and C wavelengths of the Fraunhofer spectrum.

[0088] The focal length values ​​disclosed in the optical parameter table of the embodiment are calculated based on the refractive index of the wavelength band implemented by the optical system, and the primary wavelength (primary wavelength) implemented in the embodiment of the present invention is 450 nanometers, so the focal length value of the present invention is calculated based on the refractive index of the material at 450 nanometers.

[0089] In addition, in this embodiment, the object-side surfaces 15, 25, 35, 45 and the image-side surfaces 16, 26, 36, 46 of the first lens 1, the second lens 2, the third lens 3 and the fourth lens 4, a total of eight surfaces, are aspherical surfaces, wherein the object-side surfaces 15, 25, 35, 45 and the image-side surfaces 16, 26, 36, 46 are general even asphere surfaces. These aspherical surfaces are defined according to the following formula (1):

[0090]

[0091] in:

[0092] Y: the vertical distance between the point on the aspheric curve and the optical axis I;

[0093] Z: Depth of the aspherical surface (the vertical distance between the point on the aspherical surface that is Y away from the optical axis I and the tangent plane that is tangent to the vertex on the aspherical optical axis I);

[0094] R: radius of curvature of the lens surface at the near optical axis I;

[0095] K: cone coefficient;

[0096] a i : i-th order aspheric coefficient.

[0097] The aspheric coefficients of the various items from the object side surface 15 of the first lens 1 to the image side surface 46 of the fourth lens 4 in formula (1) are as follows: Fig. 9 As shown. Among them, Fig. 9 The column number 15 in the middle indicates the aspheric coefficient of the object side surface 15 of the first lens 1, and the other columns are similar. In this embodiment, the second-order aspheric coefficient a2 of each aspheric surface is zero, so it is not listed in Fig. 9 middle.

[0098] In addition, the relationship between the important parameters of the optical imaging lens 10 of the first embodiment is as follows: Fig.42 , 43 shown.

[0099] in,

[0100] T1 is the thickness of the first lens 1 on the optical axis I;

[0101] T2 is the thickness of the second lens 2 on the optical axis I;

[0102] T3 is the thickness of the third lens 3 on the optical axis I;

[0103] T4 is the thickness of the fourth lens 4 on the optical axis I;

[0104] TF is the thickness of the filter 8 on the optical axis I;

[0105] CG is the thickness of the protective cover 9 on the optical axis I;

[0106] G12 is the air gap between the first lens 1 and the second lens 2 on the optical axis I;

[0107] G23 is the air gap between the second lens 2 and the third lens 3 on the optical axis I;

[0108] G34 is the air gap between the third lens 3 and the fourth lens 4 on the optical axis I;

[0109] G4F is the air gap between the fourth lens 4 and the filter 8 on the optical axis I;

[0110] GFP is the air gap between the filter 8 and the imaging surface 99 on the optical axis I;

[0111] AAG is the sum of three air gaps between the first lens 1 to the fourth lens 4 on the optical axis I, that is, the sum of G12, G23, and G34;

[0112] ALT is the sum of the thicknesses of the four lenses from the first lens 1 to the fourth lens 4 on the optical axis I, that is, the sum of T1, T2, T3, and T4;

[0113] TL is the distance from the object side surface 15 of the first lens 1 to the image side surface 46 of the fourth lens 4 on the optical axis I;

[0114] TTL is the distance from the object side surface 15 of the first lens 1 to the imaging surface 99 on the optical axis I;

[0115] BFL is the distance from the image side surface 46 of the fourth lens 4 to the imaging surface 99 on the optical axis I, that is, the sum of G4F, TF, and GFP;

[0116] EFL is the effective focal length of the optical imaging lens 10;

[0117] HFOV is the half viewing angle of the optical imaging lens 10;

[0118] ImgH is the image height of the optical imaging lens 10;

[0119] Fno is the aperture value of the optical imaging lens 10;

[0120] EPD is the entrance pupil diameter of the optical imaging lens 10 , which is equal to the ratio of the effective focal length to the aperture value.

[0121] In addition, define:

[0122] Tavg is the average thickness of four lenses from the first lens 1 to the fourth lens 4 on the optical axis I, that is, the average thickness of T1, T2, T3, and T4;

[0123] Tmax is the maximum value of the thicknesses of the four lenses of the first lens 1 to the fourth lens 4 on the optical axis I, that is, the maximum value among T1, T2, T3, and T4;

[0124] Tmin is the minimum value of the thickness of the four lenses of the first lens 1 to the fourth lens 4 on the optical axis I, that is, the minimum value among T1, T2, T3, and T4;

[0125] Gmax is the maximum value of the three air gaps of the first lens 1 to the fourth lens 4 on the optical axis I, that is, the maximum value among G12, G23, and G34;

[0126] f1 is the focal length of the first lens 1;

[0127] f2 is the focal length of the second lens 2;

[0128] f3 is the focal length of the third lens 3;

[0129] f4 is the focal length of the fourth lens 4;

[0130] n 1 is the nd refractive index of the first lens 1;

[0131] n2 is the nd refractive index of the second lens 2;

[0132] n3 is the nd refractive index of the third lens 3;

[0133] n4 is the nd refractive index of the fourth lens 4;

[0134] V 1 is the Vd Abbe number of the first lens 1;

[0135] V2 is the Vd Abbe number of the second lens 2;

[0136] V3 is the Vd Abbe number of the third lens 3;

[0137] V4 is the Vd Abbe number of the fourth lens 4.

[0138] Also refer to 7A to 7D , Fig. 7A The diagram of the first embodiment illustrates the longitudinal spherical aberration (Longitudinal Spherical Aberration) on the imaging surface 99 when the wavelength is 405nm, 450nm and 500nm. Figure 7B and Figure 7C The figures respectively illustrate the field curvature aberration in the sagittal direction and the field curvature aberration in the tangential direction on the imaging surface 99 of the first embodiment when the wavelength is 405nm, 450nm and 500nm. Fig.7DThe diagrams of FIG. 1 illustrate the distortion aberration of the first embodiment on the imaging surface 99 when the wavelength is 405 nm, 450 nm and 500 nm. The longitudinal spherical aberration of the first embodiment is as follows: Fig. 7A As shown, the curves formed by each wavelength are very close and close to the middle, indicating that the off-axis light rays of different heights of each wavelength are concentrated near the imaging point. It can be seen from the deflection amplitude of the curve of each wavelength that the imaging point deviation of the off-axis light rays of different heights is controlled within the range of ±4.00E-003 microns. Therefore, the first embodiment does significantly improve the spherical aberration of the same wavelength. In addition, the distances between the three representative wavelengths are also very close to each other, representing that the imaging positions of the light rays of different wavelengths are already very concentrated, thereby significantly improving the chromatic aberration.

[0139] exist Figure 7B and Figure 7C In the two field curvature aberration diagrams, the focal length variation of the three representative wavelengths in the entire field of view falls within ±15.00 microns, indicating that the optical system of the first embodiment can effectively eliminate aberrations. Fig.7D The distortion aberration diagram shows that the distortion aberration of this embodiment is maintained within the range of ±4%, indicating that the distortion aberration of the first embodiment meets the imaging quality requirements of the optical system. It is thus explained that compared with the existing optical lens, the first embodiment can still provide good imaging quality under the condition that the system length has been shortened to 1.868 mm. Therefore, the first embodiment can provide an optical imaging lens with a small aperture value and excellent imaging quality while maintaining good optical performance.

[0140] Fig.10 FIG. 4 is a schematic diagram of an optical imaging lens according to a second embodiment of the present invention. FIG. 11A to FIG. 11D The longitudinal spherical aberration and various aberration diagrams of the optical imaging lens of the second embodiment. Fig.10 , a second embodiment of the optical imaging lens 10 of the present invention is substantially similar to the first embodiment, and the differences between the two are as follows: the optical data, aspheric coefficients and parameters of the lenses 1, 2, 3 and 4 are more or less different. It should be noted that, in order to clearly show the drawings, Fig.10 Part of the numbers of the optical axis area and the circumferential area having a surface shape similar to that of the first embodiment are omitted.

[0141] Detailed optical data of the optical imaging lens 10 of the second embodiment are as follows: Fig.12 As shown, the effective focal length of the optical imaging lens 10 of the second embodiment is 1.553 mm, the half viewing angle is 14.326 degrees, the system length is 2.029 mm, the aperture value is 1.450, and the image height is 0.407 mm.

[0142] like Fig.13 As shown, Fig.13 Then, each aspheric coefficient in the above formula (1) is obtained from the object side surface 15 of the first lens 1 to the image side surface 46 of the fourth lens 4 in the second embodiment.

[0143] In addition, the relationship between the important parameters of the optical imaging lens 10 of the second embodiment is as follows: Fig.42 , 43 shown.

[0144] The longitudinal spherical aberration of the second embodiment is as follows: Fig.11A As shown in the figure, the imaging point deviation of off-axis light at different heights is controlled within the range of ±0.0165 mm. Fig. 11B and Fig. 11C In the two field curvature aberration diagrams, the focal length variation of the three representative wavelengths in the entire field of view falls within ±28.000 microns. Fig.11D The distortion diagram shows that the distortion of this embodiment is maintained within the range of ±1.3%.

[0145] It can be known from the above description that the half viewing angle of the second embodiment is greater than the half viewing angle of the first embodiment. Therefore, compared with the first embodiment, the second embodiment has a larger angle range for receiving images. The image height of the second embodiment is greater than the image height of the first embodiment. Therefore, compared with the first embodiment, the second embodiment has better sensitivity. In addition, the distortion aberration of the second embodiment is less than the distortion aberration of the first embodiment, and has better imaging quality.

[0146] Fig.14 FIG. 4 is a schematic diagram of an optical imaging lens according to a third embodiment of the present invention. FIG. 15A to FIG. 15D The longitudinal spherical aberration and various aberration diagrams of the optical imaging lens of the third embodiment. Fig.14 , a third embodiment of the optical imaging lens 10 of the present invention is substantially similar to the first embodiment, and the differences between the two are as follows: the optical data, aspheric coefficients and parameters between these lenses 1, 2, 3 and 4 are more or less different. In addition, in this embodiment, the first lens 1 has a negative refractive power, the circumferential region 153 of the object side surface 15 of the first lens 1 is a concave surface, and the circumferential region 163 of the image side surface 16 of the first lens 1 is a concave surface. The second lens 2 has a positive refractive power, the optical axis region 261 of the image side surface 26 of the second lens 2 is a convex surface, and its circumferential region 263 is a convex surface. It should be noted here that in order to clearly display the drawings, Fig.14 Part of the numbers of the optical axis area and the circumferential area having a surface shape similar to that of the first embodiment are omitted.

[0147] Detailed optical data of the optical imaging lens 10 of the third embodiment are as follows: Fig.16As shown, the effective focal length of the optical imaging lens 10 of the third embodiment is 2.234 mm, the half viewing angle is 9.532 degrees, the system length is 4.301 mm, the aperture value is 1.667, and the image height is 0.380 mm.

[0148] like Fig.17 As shown, Fig.17 Then, each aspheric coefficient in the above formula (1) is obtained from the object side surface 15 of the first lens 1 to the image side surface 46 of the fourth lens 4 in the third embodiment.

[0149] In addition, the relationship between the important parameters of the optical imaging lens 10 of the third embodiment is as follows: Fig.42 , 43 shown.

[0150] The longitudinal spherical aberration of the third embodiment is as follows: Fig.15A As shown in the figure, the imaging point deviation of off-axis light at different heights is controlled within the range of ±0.073 mm. Fig. 15B and Fig. 15C In the two field curvature aberration diagrams, the focal length variation of the three representative wavelengths in the entire field of view falls within ±0.14 mm. Fig.15D The distortion diagram shows that the distortion of this embodiment is maintained within the range of ±1.8%.

[0151] From the above description, it can be known that the image height of the third embodiment is greater than that of the first embodiment. Therefore, compared with the first embodiment, the third embodiment has better sensitivity. In addition, the distortion aberration of the third embodiment is less than that of the first embodiment, and has better imaging quality.

[0152] Fig.18 FIG. 4 is a schematic diagram of an optical imaging lens according to a fourth embodiment of the present invention. FIG. 19A to FIG. 19D The longitudinal spherical aberration and various aberration diagrams of the optical imaging lens of the fourth embodiment. Fig.18 , a fourth embodiment of the optical imaging lens 10 of the present invention is substantially similar to the first embodiment, and the differences between the two are as follows: the optical data, aspheric coefficients and parameters between these lenses 1, 2, 3 and 4 are more or less different. In addition, in this embodiment, the circumferential area 163 of the image side surface 16 of the first lens 1 is a concave surface. The second lens 2 has a positive refractive power, the circumferential area 253 of the object side surface 25 of the second lens 2 is a concave surface, and the circumferential area 263 of the image side surface 26 of the second lens 2 is a convex surface. It should be noted here that in order to clearly show the drawing, Fig.18 Part of the numbers of the optical axis area and the circumferential area having a surface shape similar to that of the first embodiment are omitted.

[0153] Detailed optical data of the optical imaging lens 10 of the fourth embodiment are as follows: Fig. 20As shown, the effective focal length of the optical imaging lens 10 of the fourth embodiment is 1.428 mm, the half viewing angle is 14.811 degrees, the system length is 1.908 mm, the aperture value is 1.260, and the image height is 0.380 mm.

[0154] like Fig.21 As shown, Fig.21 Then, each aspheric coefficient in the above formula (1) is obtained from the object side surface 15 of the first lens 1 to the image side surface 46 of the fourth lens 4 in the fourth embodiment.

[0155] In addition, the relationship between the important parameters of the optical imaging lens 10 of the fourth embodiment is as follows: Fig.42 , 43 shown.

[0156] The longitudinal spherical aberration of the fourth embodiment is as follows: Fig.19A As shown in the figure, the imaging point deviation of off-axis light at different heights is controlled within the range of ±7.00E-003 mm. Fig.19B and Fig.19C In the two field curvature aberration diagrams, the focal length variation of the three representative wavelengths in the entire field of view falls within ±15.00 microns. Fig.19D The distortion diagram shows that the distortion of this embodiment is maintained within the range of ±0.9%.

[0157] It can be known from the above description that the half viewing angle of the fourth embodiment is greater than the half viewing angle of the first embodiment. Therefore, compared with the first embodiment, the fourth embodiment has a larger angle range for receiving images. The image height of the fourth embodiment is greater than the image height of the first embodiment. Therefore, compared with the first embodiment, the fourth embodiment has better sensitivity. In addition, the distortion aberration of the fourth embodiment is less than the distortion aberration of the first embodiment, and has better imaging quality.

[0158] Fig. 22 FIG. 4 is a schematic diagram of an optical imaging lens according to a fifth embodiment of the present invention. FIG. 23A to FIG. 23D The longitudinal spherical aberration and various aberration diagrams of the optical imaging lens of the fifth embodiment. Fig. 22 , a fifth embodiment of the optical imaging lens 10 of the present invention is substantially similar to the first embodiment, and the differences between the two are as follows: the optical data, aspheric coefficients and parameters of these lenses 1, 2, 3 and 4 are more or less different. In addition, the optical axis area 251 of the object side surface 25 of the second lens 2 is concave, and its circumferential area 253 is concave. The third lens 3 has a positive refractive power. The fourth lens 4 has a negative refractive power. It should be noted here that in order to clearly show the drawing, Fig. 22 Part of the numbers of the optical axis area and the circumferential area having a surface shape similar to that of the first embodiment are omitted.

[0159] Detailed optical data of the optical imaging lens 10 of the fifth embodiment are as follows: Fig.24 As shown, the effective focal length of the optical imaging lens 10 of the fifth embodiment is 1.419 mm, the half viewing angle is 12.274 degrees, the system length is 1.655 mm, the aperture value is 1.400, and the image height is 0.300 mm.

[0160] like Fig.25 As shown, Fig.25 Then, each aspheric coefficient in the above formula (1) is obtained from the object side surface 15 of the first lens 1 to the image side surface 46 of the fourth lens 4 in the fifth embodiment.

[0161] In addition, the relationship between the important parameters of the optical imaging lens 10 of the fifth embodiment is as follows: Fig.42 , 43 shown.

[0162] The longitudinal spherical aberration of the fifth embodiment is as follows: Fig.23A As shown in the figure, the imaging point deviation of off-axis light at different heights is controlled within the range of ±0.0102 mm. Fig. 23B and Fig.23C In the two field curvature aberration diagrams, the focal length variation of the three representative wavelengths in the entire field of view falls within ±37.00 microns. Fig.23D The distortion diagram shows that the distortion of this embodiment is maintained within the range of ±3.2%.

[0163] It can be known from the above description that the system length of the fifth embodiment is shorter than that of the first embodiment. Therefore, compared with the first embodiment, the fifth embodiment has a smaller volume. The aperture of the fifth embodiment is larger than that of the first embodiment. Therefore, compared with the first embodiment, the fifth embodiment has a larger amount of light entering. The image height of the fifth embodiment is larger than that of the first embodiment. Therefore, compared with the first embodiment, the fifth embodiment has better sensitivity. In addition, the distortion aberration of the fifth embodiment is smaller than that of the first embodiment, and has better imaging quality.

[0164] Fig.26 FIG. 4 is a schematic diagram of an optical imaging lens according to a sixth embodiment of the present invention. FIG. 27A to FIG. 27D The longitudinal spherical aberration and various aberration diagrams of the optical imaging lens of the sixth embodiment. Fig.26 , a sixth embodiment of the optical imaging lens 10 of the present invention is substantially similar to the first embodiment, and the differences between the two are as follows: the optical data, aspheric coefficients and parameters of the lenses 1, 2, 3 and 4 are more or less different. In addition, in this embodiment, the third lens 3 has a positive refractive power. It should be noted that, in order to clearly show the diagram, Fig.26 Part of the numbers of the optical axis area and the circumferential area having a surface shape similar to that of the first embodiment are omitted.

[0165] Detailed optical data of the optical imaging lens 10 of the sixth embodiment are as follows: Fig.28 As shown, the effective focal length of the optical imaging lens 10 of the sixth embodiment is 1.458 mm, the half viewing angle is 12.274 degrees, the system length is 1.973 mm, the aperture value is 1.260, and the image height is 0.309 mm.

[0166] like Fig.29 As shown, Fig.29 Then, each aspheric coefficient in the above formula (1) is obtained from the object side surface 15 of the first lens element 1 to the image side surface 46 of the fourth lens element 4 in the sixth embodiment.

[0167] In addition, the relationship between the important parameters of the optical imaging lens 10 of the sixth embodiment is as follows: Fig.44 , 45 shown.

[0168] The longitudinal spherical aberration of the sixth embodiment is as follows: Fig.27A As shown in the figure, the imaging point deviation of off-axis light at different heights is controlled within the range of ±6.20E-003 mm. Fig.27B and Fig.27C In the two field curvature aberration diagrams, the focal length variation of the three representative wavelengths in the entire field of view falls within ±14.00 microns. Fig.27D The distortion diagram shows that the distortion of this embodiment is maintained within the range of ±2.8%.

[0169] From the above description, it can be known that the image height of the sixth embodiment is greater than that of the first embodiment. Therefore, compared with the first embodiment, the sixth embodiment has better sensitivity. In addition, the distortion aberration of the sixth embodiment is less than that of the first embodiment, and has better imaging quality.

[0170] Fig.30 FIG. 4 is a schematic diagram of an optical imaging lens according to a seventh embodiment of the present invention. FIG. 31A to FIG. 31D The longitudinal spherical aberration and various aberration diagrams of the optical imaging lens of the seventh embodiment are shown in FIG. Fig.30 , a seventh embodiment of the optical imaging lens 10 of the present invention is substantially similar to the first embodiment, and the differences between the two are as follows: the optical data, aspheric coefficients and parameters of the lenses 1, 2, 3 and 4 are more or less different. In addition, in this embodiment, the optical axis region 161 of the image side surface 16 of the first lens 1 is a convex surface. The optical axis region 351 of the object side surface 35 of the third lens 3 is a concave surface. It should be noted here that in order to clearly show the drawing, Fig.30 Part of the numbers of the optical axis area and the circumferential area having a surface shape similar to that of the first embodiment are omitted.

[0171] Detailed optical data of the optical imaging lens 10 of the seventh embodiment are as follows: Fig.32 As shown, the effective focal length of the optical imaging lens 10 of the seventh embodiment is 1.436 mm, the half viewing angle is 12.274 degrees, the system length is 1.896 mm, the aperture value is 1.260, and the image height is 0.311 mm.

[0172] like Fig.33 As shown, Fig.33 Then, each aspheric coefficient in the above formula (1) is obtained from the object side surface 15 of the first lens element 1 to the image side surface 46 of the fourth lens element 4 in the seventh embodiment.

[0173] In addition, the relationship between the important parameters of the optical imaging lens 10 of the seventh embodiment is as follows: Fig.44 , 45 shown.

[0174] The longitudinal spherical aberration of the seventh embodiment is as follows: Fig.31A As shown in the figure, the imaging point deviation of off-axis light at different heights is controlled within the range of ±0.022 mm. Fig.31B and Fig. 31C In the two field curvature aberration diagrams, the focal length variation of the three representative wavelengths in the entire field of view falls within ±22.00 microns. Fig.31D The distortion diagram shows that the distortion of this embodiment is maintained within the range of ±1.25%.

[0175] From the above description, it can be known that the image height of the seventh embodiment is greater than that of the first embodiment. Therefore, compared with the first embodiment, the seventh embodiment has better sensitivity. In addition, the distortion aberration of the seventh embodiment is smaller than that of the first embodiment, and has better imaging quality.

[0176] Fig.34 is a schematic diagram of an optical imaging lens according to an eighth embodiment of the present invention. FIG. 35A to FIG. 35D The longitudinal spherical aberration and various aberration diagrams of the optical imaging lens of the eighth embodiment are shown in FIG. Fig.34 , an eighth embodiment of the optical imaging lens 10 of the present invention is substantially similar to the first embodiment, and the differences between the two are as follows: the optical data, aspheric coefficients and parameters between these lenses 1, 2, 3 and 4 are more or less different. In addition, in this embodiment, the circumferential area 163 of the image side surface 16 of the first lens 1 is a concave surface. The circumferential area 453 of the object side surface 45 of the fourth lens 4 is a concave surface. It should be noted here that in order to clearly show the drawing, Fig.34 Part of the numbers of the optical axis area and the circumferential area having a surface shape similar to that of the first embodiment are omitted.

[0177] Detailed optical data of the optical imaging lens 10 of the eighth embodiment are as follows: Fig.36As shown, the effective focal length of the optical imaging lens 10 of the eighth embodiment is 1.425 mm, the half viewing angle is 12.274 degrees, the system length is 2.114 mm, the aperture value is 1.260, and the image height is 0.301 mm.

[0178] like Fig.37 As shown, Fig.37 Then, each aspheric coefficient in the above formula (1) is obtained from the object side surface 15 of the first lens element 1 to the image side surface 46 of the fourth lens element 4 in the eighth embodiment.

[0179] In addition, the relationship between the important parameters of the optical imaging lens 10 of the eighth embodiment is as follows: Fig.44 , 45 shown.

[0180] The longitudinal spherical aberration of the eighth embodiment is as follows: Fig.35A As shown in the figure, the imaging point deviation of off-axis light at different heights is controlled within the range of ±0.0185 mm. Fig.35B and Fig.35C In the two field curvature aberration diagrams, the focal length variation of the three representative wavelengths in the entire field of view falls within ±19.00 microns. Fig.35D The distortion diagram shows that the distortion of this embodiment is maintained within the range of ±4.5%.

[0181] From the above description, it can be known that the image height of the eighth embodiment is greater than that of the first embodiment. Therefore, compared with the first embodiment, the eighth embodiment has better sensitivity.

[0182] Fig.38 is a schematic diagram of an optical imaging lens according to a ninth embodiment of the present invention. FIG. 39A to FIG. 39D The longitudinal spherical aberration and various aberration diagrams of the optical imaging lens of the ninth embodiment are shown in FIG. Fig.38 , a ninth embodiment of the optical imaging lens 10 of the present invention is substantially similar to the first embodiment, and the differences between the two are as follows: the optical data, aspheric coefficients and parameters between these lenses 1, 2, 3 and 4 are more or less different. In addition, in this embodiment, the optical axis area 151 of the object side surface 15 of the first lens 1 is a concave surface, and its circumferential area 153 is a concave surface. The optical axis area 161 of the image side surface 16 of the first lens 1 is a convex surface. The second lens 2 has a positive refractive power. It should be noted here that in order to clearly show the drawing, Fig.38 Part of the numbers of the optical axis area and the circumferential area having a surface shape similar to that of the first embodiment are omitted.

[0183] Detailed optical data of the optical imaging lens 10 of the ninth embodiment are as follows: Fig.40As shown, the effective focal length of the optical imaging lens 10 of the ninth embodiment is 0.816 mm, the half viewing angle is 12.274 degrees, the system length is 2.199 mm, the aperture value is 1.260, and the image height is 0.167 mm.

[0184] like Fig.41 As shown, Fig.41 Then, each aspheric coefficient in the above formula (1) is obtained from the object side surface 15 of the first lens element 1 to the image side surface 46 of the fourth lens element 4 in the ninth embodiment.

[0185] In addition, the relationship between the important parameters of the optical imaging lens 10 of the ninth embodiment is as follows: Fig.44 , 45 shown.

[0186] The longitudinal spherical aberration of the ninth embodiment is as follows: Fig.39A As shown in the figure, the imaging point deviation of off-axis light at different heights is controlled within the range of ±0.032 mm. Fig.39B and Fig.39C In the two field curvature aberration diagrams, the focal length variation of the three representative wavelengths in the entire field of view falls within ±40.00 microns. Fig.39D The distortion diagram shows that the distortion of this embodiment is maintained within the range of ±6.2%.

[0187] It can be seen from the above description that the ninth embodiment is easy to manufacture and thus has a higher yield rate.

[0188] In summary, refer to Figure 42 to Figure 45 , Figure 42 to Figure 45 The optical imaging lens 10 of the embodiment of the present invention can obtain the following effects and advantages:

[0189] 1. When the optical axis region 361 of the image side surface 36 of the third lens element 3 and the optical axis region 461 of the image side surface 46 of the fourth lens element 4 are concave, the aberration of the central field of view of the imaging surface 99 can be corrected. When the surface shape of the specific lens circumferential region, such as the circumferential region 463 of the image side surface 46 of the fourth lens element 4 is convex, the distortion of the peripheral field of view can be further corrected. After adjusting the entrance pupil diameter and the air gap to achieve the ratio limit of EPD / AAG≥2.500, the optical imaging lens 10 of the present invention can increase the light flux while having better imaging quality. The preferred range of EPD / AAG is 2.500≦EPD / AAG≦6.500.

[0190] 2. When the optical axis region 361 of the image side surface 36 of the third lens element 3 and the optical axis region 461 of the image side surface 46 of the fourth lens element 4 are concave, the aberration of the central field of view of the imaging surface 99 can be corrected. When the surface shape of the specific lens circumferential region, such as the circumferential region 353 of the object side surface 35 of the third lens element 3 and the circumferential region 463 of the image side surface 46 of the fourth lens element 4 are convex, the distortion of the peripheral field of view can be further corrected. After adjusting the entrance pupil diameter, the air gap and the back focal length to achieve the ratio limit of EPD / (AAG+BFL)≥1.000, the optical imaging lens 10 of the present invention can have better imaging quality while reducing the system length and increasing the light flux. The preferred range of EPD / (AAG+BFL) is 1.000≦EPD / (AAG+BFL)≦1.500.

[0191] 3. When the circumferential region 453 of the object-side surface 45 of the fourth lens element 4 is a convex surface, in combination with other surface shape restrictions, it is beneficial to further reduce distortion aberration.

[0192] Fourth, when the optical axis region 461 of the image-side surface 46 of the fourth lens element 4 is concave, the aberration of the central field of view of the imaging surface 99 can be corrected. In addition, when the surface shape of the specific lens circumferential region, such as the circumferential region 353 of the object-side surface 35 of the third lens element 3 and the circumferential region 463 of the image-side surface 46 of the fourth lens element 4 are convex, the distortion of the peripheral field of view can be further corrected. After adjusting the entrance pupil diameter and the image height to achieve the ratio limit of EPD / ImgH≥2.600, the optical imaging lens 10 of the present invention can increase the light flux and balance the system focal length and half viewing angle while having better imaging quality, wherein the preferred range of EPD / ImgH is 2.600≦EPD / ImgH≦4.000.

[0193] 5. When the invention satisfies one of the following conditions: the refractive power of the first lens 1 is positive, the circumferential area 153 of the object side surface 15 of the first lens 1 is convex, the circumferential area 163 of the image side surface 16 of the first lens 1 is convex, the refractive power of the second lens 2 is negative, the optical axis area 261 of the image side surface 26 of the second lens 2 is concave, and the circumferential area 263 of the image side surface 26 of the second lens 2 is concave, it is beneficial to correct field curvature aberration and improve imaging quality.

[0194] 6. In order to shorten the length of the lens system and ensure the imaging quality, and considering the difficulty of manufacturing, the air gap between the lenses is reduced or the thickness of the lenses is appropriately shortened as a means and a specific image height limit is matched. When the numerical limit of the following conditional expression is met, the embodiment of the present invention can have a better configuration, and the aberration and distortion of the optical imaging lens 10 can be improved. When the better range is met, the spherical aberration can be further improved.

[0195] in,

[0196] The optical imaging lens 10 complies with TTL / ImgH≥4.900, and the preferred range is 4.900≦TTL / ImgH≦12.500;

[0197] The optical imaging lens 10 meets (T 1+T2) / (G12+G23)≥3.200, and the preferred range is 3.200≦(T 1+T2) / (G12+G23)≦15.000;

[0198] The optical imaging lens 10 meets (T1+T2)(G12+G23+BFL)≥0.600, and the preferred range is 0.600≦(T1+T2)(G12+G23+BFL)≦2.200;

[0199] The optical imaging lens 10 meets Tmin / G34≤1.200, and the preferred range is 0.150≦Tmin / G34≦1.200;

[0200] The optical imaging lens 10 meets (G12+G23+T3) / ImgH≥0.500, and the preferred range is 0.500≦(G12+G23+T3) / ImgH≦1.300;

[0201] The optical imaging lens 10 meets (BFL+T3) / (G12+G23)≥3.500, and the preferred range is 3.500≦(BFL+T3) / (G12+G23)≦17.000;

[0202] The optical imaging lens 10 meets TL / (G12+G23)≥6.100, and the preferred range is 6.100≦TL / (G12+G23)≦31.000;

[0203] The optical imaging lens 10 meets BFL / ImgH≥1.000, and the preferred range is 1.000≦BFL / ImgH≦2.400;

[0204] The optical imaging lens 10 meets (AAG+BFL) / ImgH≥1.600, and the preferred range is 1.600≦(AAG+BFL) / ImgH≦2.800; and

[0205] The optical imaging lens 10 meets (T1+T2+BFL) / (G12+G23)≧6.900, and the preferred range is 6.900≦(T1+T2+BFL) / (G12+G23)≦28.000.

[0206] 7. In order to achieve both a larger light flux and better imaging quality, in addition to balancing the aperture value and the system focal length to achieve a suitable entrance pupil diameter, the thickness of each lens and the air gap in the system need to be adjusted. When the numerical limits of the following conditional expressions are met, the embodiments of the present invention can have a better configuration, and the aberration and distortion of the optical imaging lens 10 can be improved. When the better range is met, the spherical aberration can be further improved.

[0207] in,

[0208] The optical imaging lens 10 meets EPD / AAG≥2.500, and the preferred range is 2.500≦EPD / AAG≦6.500;

[0209] The optical imaging lens 10 meets the requirement of EPD / (AAG+BFL)≥1.000, and the preferred range is 1.000≦EPD / (AAG+BFL)≦1.500;

[0210] The optical imaging lens 10 meets EPD / ImgH≥2.600, and the preferred range is 2.600≦EPD / ImgH≦4.000;

[0211] The optical imaging lens 10 meets TTL / (EPD+Tmax)≤1.400, and the preferred range is 1.000≦TTL / (EPD+Tmax)≦1.400;

[0212] The optical imaging lens 10 meets (T 1+T2) / (Fno*(G12+G23))≥2.600, and the preferred range is 2.600≦(T 1+T2) / (Fno*(G12+G23))≦10.500;

[0213] The optical imaging lens 10 meets TL / (Fno*ImgH)≥2.400, and the preferred range is 2.400≦TL / (Fno*ImgH)≦6.000;

[0214] The optical imaging lens 10 meets Fno*EFL / Tavg≤9.500, and the preferred range is 6.000≦Fno*EFL / Tavg≦9.500;

[0215] The optical imaging lens 10 meets ALT / (Fno*AAG)≥1.400, and the preferred range is 1.400≦ALT / (Fno*AAG)≦5.200;

[0216] The optical imaging lens 10 meets Fno*(T 1+T3+T4) / EPD≤1.550, and the preferred range is 0.700≦Fno*(T 1+T3+T4) / EPD≦1.550;

[0217] The optical imaging lens 10 meets TL / (Fno*AAG)≥2.200, and the preferred range is 2.200≦TL / Fno*AAG≦6.000;

[0218] The optical imaging lens 10 complies with TTL / EPD≤3.250, and the preferred range is 1.500≦TTL / EPD≦3.250;

[0219] The optical imaging lens 10 meets EPD / Tavg≥1.750, and the preferred range is 1.750≦EPD / Tavg≦6.000;

[0220] The optical imaging lens 10 meets ALT / EPD≤2.250, and the preferred range is 0.650≦ALT / EPD≦2.250;

[0221] The optical imaging lens 10 meets Fno*(BFL+Tmin) / (T 1+T2+G34)≤1.300, and the preferred range is 0.600≦Fno*(BFL+Tmin) / (T 1+T2+G34)≦1.300;

[0222] The optical imaging lens 10 meets Fno*EFL / BFL≤4.800, and the preferred range is 2.400≦Fno*EFL / BFL≦4.800;

[0223] The optical imaging lens 10 meets EPD / (BFL+Tavg)≥0.870, and the preferred range is 0.870≦EPD / (BFL+Tavg)≦1.700;

[0224] The optical imaging lens 10 meets 2*ImgH*Fno / BFL≤2.050, and the preferred range is 1.000≦2*ImgH*Fno / BFL≦2.050;

[0225] The optical imaging lens 10 meets (T3+T4+BFL) / EPD≤1.400, and the preferred range is 0.700≦(T3+T4+BFL) / EPD≦1.400;

[0226] The optical imaging lens 10 meets Fno*(AAG+BFL) / (T 1+T2)≤2.650, and the preferred range is 1.000≦Fno*(AAG+BFL) / (T 1+T2)≦2.650; and

[0227] The optical imaging lens 10 meets Fno*(BFL+Tmin) / G34≤9.000, and the preferred range is 2.000≦Fno*(BFL+Tmin) / G34≦9.000.

[0228] 8. When the embodiment satisfies one of the following conditions: Fno*(T 1+T3+T4) / EPD≤1.550, EPD / (BFL+Tavg)≥0.870, (T3+T4+BFL) / EPD≤1.400, Fno*(BFL+Tmin) / G34≤9.000, TTL / EPD≤3.250, EPD / Tavg≥1.750, Tmin / G34≤1.200, ALT / EPD≤2.250, it is beneficial to improve distortion.

[0229] IX. The optical imaging lens 10 of the present invention includes a filter 8, which satisfies the following conditions: the average transmittance of light in the 360-380nm band is ≤5%; the average transmittance of light in the 400-500nm band is ≥90%; and the average transmittance of light in the 550-1150nm band is ≤5%, which is beneficial for the application of the optical imaging lens 10 in the 400-500nm blue light wavelength band, and has a significant improvement effect on field curvature, distortion or longitudinal aberration, reflecting good MTF resolution and imaging quality. The preferred restrictions are that the average transmittance of light in the 360-380nm band is ≤3%; the average transmittance of light in the 400-500nm band is ≥95%; and the average transmittance of light in the 550-1150nm band is ≤3%.

[0230] In addition, any combination of parameters of the embodiment can be selected to increase lens restrictions, so as to facilitate the design of lenses with the same structure of the present invention. In view of the unpredictability of optical system design, under the structure of the present invention, meeting the above conditions can better shorten the length of the system of the present invention, reduce the aperture value, improve the imaging quality, or improve the assembly yield to improve the shortcomings of the previous technology, and the lens of the embodiment of the present invention uses plastic material to reduce the weight of the lens and save costs.

[0231] The numerical ranges obtained by the combination ratio relationship of the optical parameters disclosed in each embodiment of the present invention, including the maximum and minimum values, can be implemented accordingly.

[0232] The contents disclosed in each embodiment of the present invention include but are not limited to optical parameters such as focal length, lens thickness, and Abbe number. For example, the present invention discloses an optical parameter A and an optical parameter B in each embodiment, wherein the ranges covered by these optical parameters, the comparison relationship between the optical parameters, and the conditional ranges covered by multiple embodiments are specifically explained as follows:

[0233] (1) The range covered by the optical parameter, for example: α2≦A≦α1 or β2≦B≦β1, α1 is the maximum value of the optical parameter A in multiple embodiments, α2 is the minimum value of the optical parameter A in multiple embodiments, β1 is the maximum value of the optical parameter B in multiple embodiments, and β2 is the minimum value of the optical parameter B in multiple embodiments.

[0234] (2) The comparative relationship between optical parameters, for example: A is greater than B or A is less than B.

[0235] (3) The conditional range covered by multiple embodiments, specifically, the combination relationship or proportional relationship obtained by possible calculation of multiple optical parameters of the same embodiment, these relationships are defined as E. E can be, for example: A+B or AB or A / B or A*B or (A*B) 1 / 2 , and E satisfies the conditional formula E≦γ1 or E≧γ2 or γ2≦E≦γ1, γ1 and γ2 are the values ​​obtained by calculating the optical parameters A and the optical parameters B of the same embodiment, and γ1 is the maximum value among multiple embodiments of the present invention, and γ2 is the minimum value among multiple embodiments of the present invention.

[0236] The ranges covered by the above optical parameters, the comparison relationship between the optical parameters, and the maximum and minimum values ​​of the conditional expressions, as well as the numerical ranges within the maximum and minimum values, are all features that can be implemented by the present invention and are within the scope disclosed by the present invention. The above is only an example and should not be limited to this.

[0237] All embodiments of the present invention can be implemented, and some feature combinations can be extracted from the same embodiment. Compared with the prior art, the feature combination can also achieve unexpected effects of the present case. The feature combination includes but is not limited to the combination of features such as face shape, refractive index and conditional formula. The disclosure of the implementation mode of the present invention is a specific embodiment to illustrate the principle of the present invention, and the present invention should not be limited to the disclosed embodiment. In other words, the embodiment and its drawings are only for demonstration of the present invention and are not limited thereto.

Claims

1. An optical imaging lens, comprising a first lens, a second lens, a third lens and a fourth lens in order from an object side to an image side along an optical axis, wherein each of the first lens to the fourth lens comprises an object-side surface facing the object side and allowing an imaging light to pass therethrough, and an image-side surface facing the image side and allowing the imaging light to pass therethrough; An optical axis region of the image-side surface of the third lens is a concave surface; A circumferential area of ​​the object-side surface of the fourth lens is a convex surface; An optical axis region of the image-side surface of the fourth lens is a concave surface; A circumferential area of ​​the image-side surface of the fourth lens is a convex surface; in, The optical imaging lens has only the above four lenses and satisfies the following condition: EPD / AAG≥2.500, wherein EPD is the entrance pupil diameter of the optical imaging lens, and AAG is the sum of the three air gaps between the first lens and the fourth lens on the optical axis.

2. An optical imaging lens, comprising a first lens, a second lens, a third lens and a fourth lens in order from an object side to an image side along an optical axis, wherein each of the first lens to the fourth lens comprises an object-side surface facing the object side and allowing an imaging light to pass therethrough, and an image-side surface facing the image side and allowing the imaging light to pass therethrough; A circumferential area of ​​the object-side surface of the third lens is a convex surface; An optical axis region of the image-side surface of the third lens is a concave surface; A circumferential area of ​​the object-side surface of the fourth lens is a convex surface; An optical axis region of the image-side surface of the fourth lens is a concave surface; A circumferential area of ​​the image-side surface of the fourth lens is a convex surface; in, The optical imaging lens has only the above four lenses and satisfies the following condition: EPD / (AAG+BFL)≥1.000, wherein EPD is an entrance pupil diameter of the optical imaging lens, AAG is a sum of three air gaps from the first lens to the fourth lens on the optical axis, and BFL is a distance from the image side surface of the fourth lens to an imaging surface on the optical axis.

3. An optical imaging lens, comprising a first lens, a second lens, a third lens and a fourth lens in order from an object side to an image side along an optical axis, wherein each of the first lens to the fourth lens comprises an object-side surface facing the object side and allowing an imaging light to pass therethrough, and an image-side surface facing the image side and allowing the imaging light to pass therethrough; A circumferential area of ​​the object-side surface of the third lens is a convex surface; An optical axis region of the image-side surface of the fourth lens is a concave surface; A circumferential area of ​​the image-side surface of the fourth lens is a convex surface; in, The optical imaging lens has only the above four lenses and satisfies the following condition: EPD / ImgH≥2.600, where EPD is the entrance pupil diameter of the optical imaging lens and ImgH is the maximum image height of the optical imaging lens.

4. The optical imaging lens of claim 1 or 2, wherein the optical imaging lens further satisfies the following condition: TL / (Fno*ImgH)≥2.400, wherein TL is a distance from the object-side surface of the first lens element to the image-side surface of the fourth lens element on the optical axis, Fno is an aperture value of the optical imaging lens, and ImgH is a maximum image height of the optical imaging lens.

5. The optical imaging lens of claim 1 or 2, wherein the optical imaging lens further satisfies the following condition: ALT / (Fno*AAG)≥1.400, wherein ALT is the sum of the thicknesses of four lenses from the first lens to the fourth lens on the optical axis, and Fno is the aperture value of the optical imaging lens.

6. The optical imaging lens of claim 1 or 2, wherein the optical imaging lens further satisfies the following condition: TL / (Fno*AAG)≥2.200, wherein TL is a distance from the object-side surface of the first lens element to the image-side surface of the fourth lens element on the optical axis, and Fno is an aperture value of the optical imaging lens.

7. The optical imaging lens of claim 1 or 2, wherein the optical imaging lens further satisfies the following condition: TTL / ImgH≥4.900, wherein TTL is a distance from the object-side surface of the first lens to an imaging surface on the optical axis, and ImgH is a maximum image height of the optical imaging lens.

8. The optical imaging lens of claim 1 or 2, wherein the optical imaging lens further satisfies the following conditional formula: (G12+G23+T3) / ImgH≥0.500, wherein G12 is an air gap between the first lens and the second lens on the optical axis, G23 is an air gap between the second lens and the third lens on the optical axis, T3 is a thickness of the third lens on the optical axis, and ImgH is a maximum image height of the optical imaging lens.

9. The optical imaging lens of claim 1 or 3, wherein the optical imaging lens further satisfies the following conditional formula: (T1+T2)(G12+G23+BFL)≥0.600, wherein T1 is the thickness of the first lens on the optical axis, T2 is the thickness of the second lens on the optical axis, G12 is the air gap between the first lens and the second lens on the optical axis, G23 is the air gap between the second lens and the third lens on the optical axis, and BFL is the distance from the image-side surface of the fourth lens to an imaging plane on the optical axis.

10. The optical imaging lens of claim 1 or 3, wherein the optical imaging lens further satisfies the following conditional formula: (BFL+T3) / (G12+G23)≥3.500, wherein BFL is a distance from the image-side surface of the fourth lens to an imaging plane on the optical axis, T3 is a thickness of the third lens on the optical axis, G12 is an air gap between the first lens and the second lens on the optical axis, and G23 is an air gap between the second lens and the third lens on the optical axis.

11. The optical imaging lens of claim 1 or 3, wherein the optical imaging lens further satisfies the following condition: TTL / (EPD+Tmax)≤1.400, wherein TTL is a distance from the object-side surface of the first lens to an imaging surface on the optical axis, and Tmax is a maximum value of four lens thicknesses from the first lens to the fourth lens on the optical axis.

12. The optical imaging lens of claim 1 or 3, wherein the optical imaging lens further satisfies the following condition: TTL / EPD≤3.250, wherein TTL is a distance from the object-side surface of the first lens to an imaging surface on the optical axis.

13. The optical imaging lens of any one of claims 1 to 3, wherein the optical imaging lens further satisfies the following conditional formula: (T1+T2) / (Fno*(G12+G23))≥2.600, wherein T1 is the thickness of the first lens on the optical axis, T2 is the thickness of the second lens on the optical axis, Fno is the aperture value of the optical imaging lens, G12 is the air gap between the first lens and the second lens on the optical axis, and G23 is the air gap between the second lens and the third lens on the optical axis.

14. The optical imaging lens according to any one of claims 1 to 3, wherein the optical imaging lens further satisfies the following conditional formula: Fno*EFL / Tavg≤9.500, wherein Fno is an aperture value of the optical imaging lens, EFL is an effective focal length of the optical imaging lens, and Tavg is an average value of thicknesses of four lenses from the first lens to the fourth lens on the optical axis.

15. The optical imaging lens according to any one of claims 1 to 3, wherein the optical imaging lens further satisfies the following conditional formula: Fno*(T1+T3+T4) / EPD≤1.550, wherein Fno is an aperture value of the optical imaging lens, T1 is a thickness of the first lens on the optical axis, T3 is a thickness of the third lens on the optical axis, and T4 is a thickness of the fourth lens on the optical axis.

16. The optical imaging lens of any one of claims 1 to 3, wherein the optical imaging lens further satisfies the following conditional formula: (T1+T2) / (G12+G23)≥3.200, wherein T1 is the thickness of the first lens on the optical axis, T2 is the thickness of the second lens on the optical axis, G12 is the air gap between the first lens and the second lens on the optical axis, and G23 is the air gap between the second lens and the third lens on the optical axis.

17. The optical imaging lens according to any one of claims 1 to 3, wherein the optical imaging lens further satisfies the following condition: EPD / Tavg≥1.750, wherein Tavg is an average value of the thicknesses of four lenses from the first lens to the fourth lens on the optical axis.

18. The optical imaging lens of any one of claims 1 to 3, wherein the optical imaging lens further satisfies the following conditional expression: Tmin / G34≤1.200, wherein Tmin is the minimum value of the thickness of four lenses from the first lens to the fourth lens on the optical axis, and G34 is the air gap between the third lens and the fourth lens on the optical axis.

19. The optical imaging lens according to any one of claims 1 to 3, wherein the optical imaging lens further satisfies the following condition: ALT / EPD≤2.250, wherein ALT is the sum of the thicknesses of four lenses from the first lens to the fourth lens on the optical axis.

20. The optical imaging lens of any one of claims 1 to 3, wherein the optical imaging lens further satisfies the following conditional formula: TL / (G12+G23)≥6.100, wherein TL is a distance from the object-side surface of the first lens to the image-side surface of the fourth lens on the optical axis, G12 is an air gap between the first lens and the second lens on the optical axis, and G23 is an air gap between the second lens and the third lens on the optical axis.

21. An optical imaging lens, comprising a first lens, a second lens, a third lens and a fourth lens in sequence along an optical axis from an object side to an image side, wherein each of the first lens to the fourth lens comprises an object-side surface facing the object side and allowing an imaging light to pass through, and an image-side surface facing the image side and allowing the imaging light to pass through; in, The optical imaging lens has only the above four lenses and satisfies the following conditional formula: The average transmittance of light in the 360-380nm band is ≤5%; The average transmittance of light in the 400-500nm band is ≥ 90%; and The average transmittance of light in the 550-1150nm band is ≤5%.

Images