Optical lens

Abstract

The application provides an optical lens, which comprises nine lenses in sequence along an optical axis from an object side to an imaging surface, and comprises the following: a first lens with negative optical power, the object side of which is a convex surface and the image side of which is a concave surface; a second lens with positive optical power, the object side of which is a convex surface and the image side of which is a concave surface; a third lens with positive optical power, the object side of which is a convex surface and the image side of which is a concave surface; a fourth lens with negative optical power, the object side of which is a concave surface and the image side of which is a convex surface; a fifth lens with positive optical power, the object side of which is a convex surface and the image side of which is a convex surface; a sixth lens with negative optical power; a seventh lens with positive optical power; an eighth lens with negative optical power; and a ninth lens with positive optical power. The optical lens provided by the application has one or more advantages of short focal length, miniaturization, large field of view, large aperture, large target surface, low distortion, low sensitivity and the like through specific surface shape matching and reasonable optical power distribution.

Description

Technical Field

[0001] This invention relates to the technical field of imaging lenses, and in particular to an optical lens. Background Technology

[0002] With the rapid development of fields such as drones, security, automobiles, meteorology, medical, VR, and AR, increasingly higher demands are being placed on the field of view of the lenses they are equipped with. Wide-angle lenses, by introducing barrel distortion, compress light at the edges of the field of view as much as possible, thus achieving ultra-wide-angle lenses. Currently, ultra-wide-angle lenses still have many problems. For example, common ultra-wide-angle lenses have relatively small apertures, resulting in insufficient light intake and unclear images in low-light environments. In addition, there are problems such as difficulty in aberration correction, large distortion, and defocusing under high and low temperature conditions. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide an optical lens with the advantage of excellent image quality.

[0004] This invention provides an optical lens comprising nine lenses, arranged sequentially along the optical axis from the object side to the imaging plane:

[0005] The first lens with negative optical power has a convex object side and a concave image side.

[0006] A second lens with positive optical power has a convex object-side surface and a concave image-side surface;

[0007] A third lens with positive optical power has a convex object-side surface and a concave image-side surface.

[0008] The fourth lens with negative optical power has a concave object side and a convex image side.

[0009] The fifth lens with positive optical power has a convex object-side surface and a convex image-side surface.

[0010] The sixth lens has negative optical power and its image-side surface is concave.

[0011] The seventh lens with positive optical power has a convex object-side surface and a convex image-side surface.

[0012] The eighth lens, which has negative optical power, has an image-side surface that is concave near the optical axis.

[0013] The ninth lens with positive optical power has an object-side surface that is convex near the optical axis and an image-side surface that is concave near the optical axis.

[0014] Wherein, the maximum field of view (FOV) of the optical lens, the effective focal length (f) of the optical lens, and the true image height (IH) corresponding to the maximum field of view of the optical lens satisfy: 60° < (FOV × f) / IH < 95°.

[0015] Further preferably, the total optical length (TTL) of the optical lens and the effective focal length (f) of the optical lens satisfy: 4.4 <TTL / f<6.5。

[0016] Further preferably, the effective focal length f of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 1.6 <f / EPD<2.1。

[0017] Further preferably, the true image height IH corresponding to the maximum field of view of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 4.2 <IH / EPD<4.6。

[0018] Further preferably, the half-aperture height SAG21 of the object-side surface of the second lens and the center thickness CT2 of the second lens satisfy: 1 <SAG21 / CT2<1.2。

[0019] Further preferably, the center thickness CT2 of the second lens and the edge thickness ET2 of the second lens satisfy: 1.4 <CT2 / ET2<2.1。

[0020] Further preferably, the effective focal length f of the optical lens, the radian value θ of the maximum field of view of the optical lens, and the true image height IH corresponding to the maximum field of view of the optical lens satisfy: 0.6 <IH / (f×θ)<0.9。

[0021] Further preferably, the center thickness CT9 of the ninth lens and the half-aperture sagitta SAG91 of the object-side surface of the ninth lens satisfy: -1.3 <CT9 / SAG91<-0.7。

[0022] Further preferably, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 2.9 <f2 / f<9.4。

[0023] Further preferably, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 3.6 <f3 / f<5.3。

[0024] Compared with existing technologies, the optical lens provided by this invention uses nine lenses with specific optical power. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the imaging quality of the optical lens. This allows the lens to have one or more advantages such as short focal length, miniaturization, large field of view, large aperture, large target surface, low distortion, and low sensitivity. Attached Figure Description

[0025] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0026] Figure 1 This is a schematic diagram of the optical lens structure in Embodiment 1 of the present invention.

[0027] Figure 2 This is an F-Theta distortion curve of the optical lens in Embodiment 1 of the present invention.

[0028] Figure 3 This is a field curvature curve diagram of the optical lens in Embodiment 1 of the present invention.

[0029] Figure 4 This is a chromatic aberration curve of the optical lens in Embodiment 1 of the present invention.

[0030] Figure 5 This is a schematic diagram of the optical lens structure in Embodiment 2 of the present invention.

[0031] Figure 6 This is the F-Theta distortion curve of the optical lens in Embodiment 2 of the present invention.

[0032] Figure 7 This is a field curvature curve diagram of the optical lens in Embodiment 2 of the present invention.

[0033] Figure 8 This is a chromatic aberration curve of the optical lens in Embodiment 2 of the present invention.

[0034] Figure 9 This is a schematic diagram of the optical lens in Embodiment 3 of the present invention.

[0035] Figure 10 This is the F-Theta distortion curve of the optical lens in Embodiment 3 of the present invention.

[0036] Figure 11 This is a field curvature curve diagram of the optical lens in Embodiment 3 of the present invention.

[0037] Figure 12 This is a chromatic aberration curve of the optical lens in Embodiment 3 of the present invention.

[0038] The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0039] To better understand this application, various aspects of this application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely illustrative of embodiments of this application and are not intended to limit the scope of this application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0040] It should be noted that in this specification, the terms "first," "second," "third," etc., are used only to distinguish one feature from another and do not imply any limitation on the features. Therefore, without departing from the teachings of the invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0041] In the accompanying drawings, the thickness, size, and shape of the lenses have been slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not strictly to scale.

[0042] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the location of the convexity is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the location of the concaveness is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the subject is called the object-side surface of the lens, and the surface of each lens closest to the imaging plane is called the image-side surface of the lens.

[0043] It should also be understood that the terms "comprising," "including," "having," "containing," and / or "comprising," when used in this specification, indicate the presence of the stated features, elements, and / or components, but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. Furthermore, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire list of features, not individual elements in the list. Additionally, when describing embodiments of this application, the word "may" is used to mean "one or more embodiments of this application." And the term "exemplary" is intended to refer to an example or illustration.

[0044] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms (e.g., those defined in common dictionaries) shall be interpreted as having the meaning consistent with their meaning in the context of the relevant art and shall not be interpreted in an idealized or overly formal sense unless expressly so specified herein.

[0045] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0046] The optical lens provided in this embodiment of the invention comprises nine lenses, which are arranged sequentially along the optical axis from the object side to the imaging plane as follows: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens.

[0047] In some embodiments, the first lens may have negative optical power, with a convex object-side surface and a concave image-side surface. The second lens may have positive optical power, with a convex object-side surface and a concave image-side surface. The third lens may have positive optical power, with a convex object-side surface and a concave image-side surface. The fourth lens may have negative optical power, with a concave object-side surface and a convex image-side surface. The fifth lens may have positive optical power, with both a convex object-side surface and a convex image-side surface. The sixth lens may have negative optical power, with either a concave or convex object-side surface and a concave image-side surface. The seventh lens may have positive optical power, with both a convex object-side surface and a convex image-side surface. The eighth lens may have negative optical power, with either a concave or convex object-side surface and a concave image-side surface near the optical axis. The ninth lens may have positive optical power, with a convex object-side surface near the optical axis and a concave image-side surface near the optical axis.

[0048] In some embodiments, the optical lens may also include an aperture stop, which may be located between the fourth and fifth lenses. It is understood that the aperture stop is used to limit the amount of light entering the lens to change the brightness of the image. When the aperture stop is located between the fourth and fifth lenses, it facilitates the correction of aperture aberrations.

[0049] In some embodiments, the optical lens may further include a filter disposed between the ninth lens and the imaging surface. The filter is used to filter out interfering light and prevent it from reaching the imaging surface of the optical lens and affecting normal imaging.

[0050] In some implementations, the maximum field of view (FOV) of the optical lens, the effective focal length (f) of the optical lens, and the true image height (IH) corresponding to the maximum field of view of the optical lens satisfy the following condition: 60° < (FOV × f) / IH < 95°. Satisfying this condition ensures that the optical lens has excellent optical performance, achieving the characteristics of high-pixel imaging. This allows for excellent capture of subject details and also helps to obtain a large field of view while reducing the deflection angle of the outgoing light rays, thereby mitigating vignetting and suppressing distortion.

[0051] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 4.4 < TTL / f < 6.5. Meeting the above conditional formula can reasonably configure the ratio of the total optical length to the effective focal length of the optical lens, which is beneficial to the miniaturized design of the optical lens. At the same time, it is also beneficial for the optical lens to have a reasonable field angle range while achieving certain focal length characteristics, so as to meet the wide-angle design of the optical lens and enable the optical lens to obtain sufficient object-side space information.

[0052] In some embodiments, the effective focal length f of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 1.6 < f / EPD < 2.1. Meeting the above conditional formula helps to improve the light-receiving ability of the optical lens by controlling the ratio of the effective focal length to the entrance pupil diameter of the optical lens, obtain as much object-side information as possible, and thus obtain imaging information with higher brightness and resolution.

[0053] In some embodiments, the true image height IH corresponding to the maximum field angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 4.2 < IH / EPD < 4.6. Meeting the above conditional formula controls the relationship between the entrance pupil diameter and the image height of the optical lens to make the width of the light beam incident on the optical lens appropriate, which is beneficial to the improvement of the image plane brightness, and makes the image plane area and the field range of the optical lens appropriate.

[0054] In some embodiments, the sagittal height SAG21 of the light-passing semi-aperture on the object side of the second lens and the central thickness CT2 of the second lens satisfy: 1 < SAG21 / CT2 < 1.2. Meeting the above conditional formula can reasonably control the surface shape of the object side of the second lens, which is beneficial to reducing the deflection angle of the light in the optical lens, thereby reducing the sensitivity of the marginal rays of the optical lens and improving the resolution.

[0055] In some embodiments, the central thickness CT2 of the second lens and the edge thickness ET2 of the second lens satisfy: 1.4 < CT2 / ET2 < 2.1. Meeting the above conditional formula can effectively balance the aberration generated by the optical lens by controlling the central thickness and the edge thickness of the second lens within a certain range. At the same time, it is also beneficial to the field curvature adjustment in engineering production, and thus is beneficial to improving the imaging quality of the optical lens.

[0056] In some embodiments, the effective focal length f of the optical lens, the radian value θ of the maximum field angle of the optical lens, and the true image height IH corresponding to the maximum field angle of the optical lens satisfy: 0.6 < IH / (f×θ) < 0.9. Meeting the above conditional formula can control the marginal distortion of the optical lens, which is beneficial to achieving the characteristics of a larger field angle and a large image plane of the optical lens. At the same time, it can effectively increase the proportion of the marginal field of the optical lens in the entire image plane, enable the optical lens to meet the high-pixel characteristics, and improve the imaging quality of the optical lens.

[0057] In some embodiments, the central thickness CT9 of the ninth lens and the sagittal height SAG91 of the clear aperture radius on the object side of the ninth lens satisfy: -1.3 < CT9 / SAG91 < -0.7. Meeting the above conditional formula can avoid the excessive central thickness of the ninth lens or the excessive curvature of the object side while meeting the bending force, thereby increasing the lens manufacturing difficulty, and thus reducing the production cost.

[0058] In some embodiments, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 2.9 < f2 / f < 9.4. Meeting the above conditional formula is beneficial to cooperate with the first lens to make large-angle light rays enter the optical lens, thereby expanding the field angle of the optical lens. At the same time, it is also beneficial to correct the astigmatism and chromatic aberration of the optical lens and improve the imaging quality of the optical lens.

[0059] In some embodiments, the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 3.6 < f3 / f < 5.3. Meeting the above conditional formula, by setting the third lens with a positive optical power and defining the ratio of the focal length of the third lens to the effective focal length of the optical lens, it is beneficial to adjust the light ray trend from the first lens and the second lens, and at the same time, it is beneficial to correct the marginal aberration and improve the imaging resolution.

[0060] In some embodiments, the focal length f4 of the fourth lens and the effective focal length f of the optical lens satisfy: -20 < f4 / f < -6. Meeting the above conditional formula, as the intermediate lens of the imaging lens group, the negative refractive power provided by the fourth lens for the optical lens can better constrain the light beam, so it can be used to correct the chromatic aberration of the optical lens. At the same time, it can perform intermediate correction on the aberration generated by the decentration difference of each lens on the object side and reduce the correction pressure of the subsequent lens group.

[0061] In some embodiments, the focal length f6 of the sixth lens and the effective focal length f of the optical lens satisfy: -2.4 < f6 / f < -1.4. Meeting the above conditional formula, reasonably controlling the focal length value of the sixth lens can slowly lift the large-field light rays, making the parallel light trend of the light beam change to a divergent trend, which is beneficial to controlling the back focal length of the lens, beneficial to achieving a large target surface and reducing the main ray incident angle.

[0062] In some embodiments, the focal length f8 of the eighth lens and the effective focal length f of the optical lens satisfy: -7.9 < f8 / f < -3.7. Meeting the above conditional formula is beneficial to expanding the width of the light beam, making the width of the light beam with a larger angle expand after passing through the first lens to the seventh lens, allowing the wide light beam to fully enter the imaging surface of the optical lens, making the optical lens have a wider field range, and being beneficial to achieving high-pixel imaging.

[0063] In some embodiments, the total optical length TTL of the optical lens and the aperture value Fno of the optical lens satisfy: 5.8mm < TTL / Fno < 9.2mm. By controlling the relationship between the total length and the aperture value of the optical lens to meet the above conditional formula, it is ensured that the optical lens can meet the requirements of large aperture and miniaturization design, enabling the optical lens to obtain sufficient light transmission in a dim environment and meeting the needs of high-quality and high-clarity shooting.

[0064] In some embodiments, the half-aperture CSD11 of the object side of the first lens and the sag SAG11 of the half-aperture of the object side of the first lens satisfy: 3.5 < CSD11 / SAG11 < 4.2. Meeting the above conditional formula is beneficial for large-angle light to enter the optical lens, resulting in a relatively high imaging quality of the optical lens. It avoids the excessive curvature of the object side surface of the first lens, reduces the processing difficulty of the first lens, avoids the problem of uneven coating caused by the excessive curvature of the first lens, and also avoids the excessive flatness of the object side of the first lens, reducing the risk of ghosting.

[0065] In some embodiments, the central thickness CT9 of the ninth lens, the sag SAG91 of the half-aperture of the object side of the ninth lens, and the sag SAG92 of the half-aperture of the image side of the ninth lens satisfy: -2.5 < (SAG91 + SAG92) / CT9 < -1.3. Meeting the above conditional formula is beneficial for controlling the refractive power and thickness of the ninth lens at various positions perpendicular to the optical axis, avoiding the ninth lens being too thick or too thin, reducing the incident angle of light on the object side surface of the ninth lens, and reducing the tolerance sensitivity of the optical lens; at the same time, the ninth lens has multiple anti-curved points, which is beneficial for correcting the distortion and field curvature generated by the object-side lens of the ninth lens, and evenly distributing the refractive power of multiple lenses near the imaging surface of the optical lens.

[0066] In some embodiments, the optical lens satisfies the following conditional formula: 2.2mm < f < 2.7mm; 170° ≤ FOV < 220°; 1.3mm < EPD < 1.5mm; 11mm < TTL < 15mm; 1.6 < Fno ≤ 2; 5.9mm < IH ≤ 6mm; where f represents the effective focal length of the optical lens, FOV represents the maximum field angle of the optical lens, EPD represents the entrance pupil diameter of the optical lens, TTL represents the total optical length of the optical lens, Fno represents the aperture value of the optical lens, and IH represents the image height corresponding to the maximum field angle of the optical lens. Meeting the above conditional formula, the optical lens has at least one or more advantages such as short focal length, large field angle, large entrance pupil diameter, short total length, large aperture, large target surface, low distortion, and low sensitivity.

[0067] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, production costs can be effectively reduced. Conversely, when the lens material is glass, the low dispersion characteristic of glass itself can effectively correct geometric chromatic aberration of the optical system. The first and fourth lenses in the optical lens provided by the present invention can be made of glass, while the second, third, fifth, sixth, seventh, eighth, and ninth lenses can be made of plastic. This glass-plastic hybrid structure effectively reduces costs, corrects aberrations, reduces size, improves thermal stability, and provides a more cost-effective optical lens product.

[0068] In some embodiments, the first, second, third, fourth, fifth, sixth, seventh, eighth, and ninth lenses can be spherical or aspherical lenses. Compared to spherical structures, aspherical structures can effectively reduce aberrations in the optical system, thereby reducing the number of lenses and their size, and better achieving lens miniaturization. More specifically, the first and fourth lenses of this invention are spherical lenses; the second, third, fifth, sixth, seventh, eighth, and ninth lenses are aspherical lenses.

[0069] In various embodiments of the present invention, when an aspherical lens is used, the shapes of each aspherical surface of the optical lens satisfy the following equations:

[0070] ;

[0071] Where z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the vertex of the surface, K is the quadratic surface coefficient, and B, C, D, E, F, G, H, I, and J are the fourth, sixth, eighth, tenth, twelfth, fourteenth, sixteenth, eighteenth, and twentieth order surface coefficients, respectively.

[0072] The present invention will be further described below with reference to several embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different; for specific differences, please refer to the parameter tables of each embodiment. The following embodiments are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any changes, substitutions, combinations, or simplifications made without departing from the innovative points of the present invention should be considered equivalent substitutions and are included within the protection scope of the present invention.

[0073] Example 1

[0074] Please see Figure 1The diagram shows a schematic of the structure of the optical lens 100 provided in Embodiment 1 of the present invention. The optical lens 100 includes, along the optical axis from the object side to the imaging surface S21, the following components in sequence: a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, an aperture ST, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9, and a filter G1.

[0075] Among them, the first lens L1 has negative optical power, its object side S1 is convex, and its image side S2 is concave.

[0076] The second lens L2 has positive optical power, its object side S3 is convex, and its image side S4 is concave.

[0077] The third lens L3 has positive optical power, its object side S5 is convex, and its image side S6 is concave.

[0078] The fourth lens L4 has negative optical power, its object side S7 is concave, and its image side S8 is convex.

[0079] The fifth lens L5 has positive optical power, its object side S9 is convex, and its image side S10 is convex.

[0080] The sixth lens L6 has negative optical power, its object side S11 is concave, and its image side S12 is concave.

[0081] The seventh lens L7 has positive optical power, its object side S13 is convex, and its image side S14 is convex.

[0082] The eighth lens L8 has negative optical power, its object side S15 is concave, and its image side S16 is concave near the optical axis.

[0083] The ninth lens L9 has positive optical power, its object side S17 is convex near the optical axis, and its image side S18 is concave near the optical axis.

[0084] The object-side surface S19 and the image-side surface S20 of filter G1 are both planar.

[0085] The imaging plane S21 is a plane.

[0086] The first lens L1 and the fourth lens L4 are glass spherical lenses; the second lens L2, the third lens L3, the fifth lens L5, the sixth lens L6, the seventh lens L7, the eighth lens L8 and the ninth lens L9 are all plastic aspherical lenses.

[0087] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0088] Table 1-1

[0089]

[0090] The surface profile parameters of the aspherical lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0091] Table 1-2

[0092]

[0093] In this embodiment, the F-Theta distortion curve, field curvature curve, and transverse chromatic aberration curve of the optical lens 100 are respectively as follows: Figure 2 , Figure 3 , Figure 4 As shown.

[0094] Figure 2 The F-Theta distortion curve of the optical lens 100 in this embodiment is shown, which represents the distortion at different field-of-view angles on the imaging plane. The horizontal axis represents the distortion value (unit: %), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the distortion value is controlled within -40% to 0, indicating that the optical lens 100 can correct distortion well.

[0095] Figure 3 The field curvature curve of the optical lens 100 in this embodiment is shown, which represents the field curvature of light in the meridional and sagittal image planes. The horizontal axis represents the offset (unit: mm), and the vertical axis represents the half field of view (unit: °). As can be seen from the figure, the field curvature of the meridional and sagittal image planes is controlled within ±0.05 mm, indicating that the optical lens 100 can correct the field curvature well.

[0096] Figure 4 The diagram shows the transverse chromatic aberration curve of the optical lens 100 in this embodiment. It represents the chromatic aberration of each wavelength relative to the center wavelength (0.555 μm) at different image heights on the imaging plane. The horizontal axis represents the transverse chromatic aberration value of each wavelength relative to the center wavelength (unit: μm), and the vertical axis represents the normalized field of view. As can be seen from the figure, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -1 μm to 3 μm, indicating that the optical lens 100 can effectively correct transverse chromatic aberration.

[0097] Example 2

[0098] Please see Figure 5 The figure shown is a schematic diagram of the structure of the optical lens 200 provided in Embodiment 2 of the present invention. The main difference between this embodiment and Embodiment 1 is that the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0099] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0100] Table 2-1

[0101]

[0102] The surface profile parameters of the aspherical lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0103] Table 2-2

[0104]

[0105] In this embodiment, the F-Theta distortion curve, field curvature curve, and transverse chromatic aberration curve of the optical lens 200 are respectively as follows: Figure 6 , Figure 7 , Figure 8 As shown.

[0106] from Figure 6 As can be seen, the distortion value is controlled within -35% to 0, indicating that the optical lens 200 can correct distortion well.

[0107] from Figure 7 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within ±0.05mm, indicating that the optical lens 200 can effectively correct the field curvature.

[0108] from Figure 8 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within 0~5μm, indicating that the optical lens 200 can correct transverse chromatic aberration well.

[0109] Example 3

[0110] Please see Figure 9 The figure shows a schematic diagram of the structure of the optical lens 300 provided in Embodiment 3 of the present invention. The main difference between this embodiment and Embodiment 1 is that the object-side surface S11 of the sixth lens L6 is a convex surface; the object-side surface S15 of the eighth lens L8 is a convex surface; and the optical parameters such as the radius of curvature and lens thickness of each lens surface are different.

[0111] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0112] Table 3-1

[0113]

[0114] The surface profile parameters of the aspherical lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0115] Table 3-2

[0116]

[0117] In this embodiment, the F-Theta distortion curve, field curvature curve, and transverse chromatic aberration curve of the optical lens 300 are respectively as follows: Figure 10 , Figure 11 , Figure 12 As shown.

[0118] from Figure 10 As can be seen, the distortion value is controlled within -15% to 0, indicating that the optical lens 300 can correct distortion well.

[0119] from Figure 11 As can be seen, the field curvature of the meridional and sagittal image planes is controlled within -0.05mm to 0.1mm, indicating that the optical lens 300 can correct the field curvature well.

[0120] from Figure 12 As can be seen, the transverse chromatic aberration of the longest and shortest wavelengths is controlled within -1μm to 3μm, indicating that the optical lens 300 can effectively correct transverse chromatic aberration.

[0121] Please refer to Table 4 for the optical characteristics corresponding to each of the above embodiments, including the effective focal length f, total optical length TTL, aperture value Fno, true image height IH corresponding to the maximum field of view, principal ray incident angle CRA at the maximum image height, maximum field of view FOV, and the values ​​corresponding to each conditional expression in each embodiment.

[0122] Table 4

[0123]

[0124] In summary, the optical lens provided by the present invention uses nine lenses with specific optical power. Through specific surface shape matching and reasonable optical power distribution, it can improve the imaging quality of the optical lens, reduce aberrations, and enhance the imaging quality of the optical lens. This allows the lens to have one or more advantages such as short focal length, miniaturization, large field of view, large aperture, large target surface, low distortion, and low sensitivity.

[0125] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0126] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. An optical lens, comprising nine pieces of lenses, characterized in that, In order from the object side to the imaging plane along the optical axis, successively comprise: a first lens with negative refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a second lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a third lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a concave surface; a fourth lens with negative refractive power, the object side surface of which is a concave surface, and the image side surface of which is a convex surface; a fifth lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; a sixth lens with negative refractive power, the image side surface of which is a concave surface; a seventh lens with positive refractive power, the object side surface of which is a convex surface, and the image side surface of which is a convex surface; an eighth lens with negative refractive power, the image side surface of which is a concave surface at the near optical axis; a ninth lens with positive refractive power, the object side surface of which is a convex surface at the near optical axis, and the image side surface of which is a concave surface at the near optical axis; wherein the maximum field of view angle FOV of the optical lens, the effective focal length f of the optical lens and the real image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 60°<(FOV×f) / IH<95°; the focal length f3 of the third lens and the effective focal length f of the optical lens satisfy: 3.6<f3 / f<5.

3.

2. The optical lens of claim 1, wherein, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 4.4<TTL / f<6.

5.

3. The optical lens of claim 1, wherein, the effective focal length f of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 1.6<f / EPD<2.

1.

4. The optical lens of claim 1, wherein, the real image height IH corresponding to the maximum field of view angle of the optical lens and the entrance pupil diameter EPD of the optical lens satisfy: 4.2<IH / EPD<4.

6.

5. The optical lens of claim 1, wherein, the object side surface half radius sag height SAG21 of the second lens and the central thickness CT2 of the second lens satisfy: 1<SAG21 / CT2<1.

2.

6. The optical lens of claim 1, wherein, the central thickness CT2 of the second lens and the edge thickness ET2 of the second lens satisfy: 1.4<CT2 / ET2<2.

1.

7. The optical lens of claim 1, wherein, the effective focal length f of the optical lens, the radian value θ of the maximum field of view angle of the optical lens and the real image height IH corresponding to the maximum field of view angle of the optical lens satisfy: 0.6<IH / (f×θ)<0.

9.

8. The optical lens of claim 1, wherein, the central thickness CT9 of the ninth lens and the object side surface half radius sag height SAG91 of the ninth lens satisfy: -1.3<CT9 / SAG91<-0.

7.

9. The optical lens of claim 1, wherein, the focal length f2 of the second lens and the effective focal length f of the optical lens satisfy: 2.9<f2 / f<9.

4.

10. The optical lens of claim 1, wherein, the total optical length TTL of the optical lens and the aperture value Fno of the optical lens satisfy: 5.8mm<TTL / Fno<9.2mm.

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