Ultra-wide-angle ultra-short-focus full-width camera lens

Abstract

The embodiment of the invention discloses an ultra-wide-angle ultra-short-focus full-width camera lens, which comprises sixteen lenses which are sequentially arranged from an object space to an image space along an optical axis, and each lens has corresponding focal power; besides, a diaphragm is arranged between the eighth lens and the ninth lens to divide the sixteen lenses into two lens groups, namely a first lens group with negative total focal power and a second lens group with positive total focal power. According to the full-frame prime lens provided by the embodiment of the invention, by using the optical structure of the 14 glass spherical lenses and the 2 glass aspherical lenses, when the full field angle is greater than or equal to 132 degrees, the distortion is small, and the purple edge phenomenon is improved. Besides, by adding the aspherical lens, the image quality of an edge field of view is also obviously improved under an ultra-short focal length, clear imaging can be realized, and the shooting feeling of almost zero distortion is achieved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of optical lenses, and in particular to an ultra-wide-angle and ultra-short-focus full-frame camera lens. Background Art

[0002] Normally, when photographers want to shoot scenes such as high-rise buildings, the sky, indoor spaces, and panoramic scenery, they need to use a fisheye lens to achieve the desired effect. However, fisheye lenses have large distortion, which makes the scenery seriously deformed. Compared with fisheye lenses, ultra-wide-angle lenses can have a wide field of view and very low distortion at the same time.

[0003] Therefore, designing a full-frame lens with ultra-wide-angle viewing angle and low distortion has broad market prospects. Summary of the invention

[0004] The present invention provides an ultra-wide-angle ultra-short-focus full-frame camera lens, which can achieve smaller distortion and improved purple fringing when the full field of view angle is ≥132°. In addition, by adding aspherical lenses, the image quality of the edge field of view is significantly improved under ultra-short focal length, and clear imaging and almost zero distortion shooting experience can be achieved.

[0005] An embodiment of the present invention provides an ultra-wide-angle ultra-short-focus full-frame camera lens, comprising a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with positive focal power, a fifth lens with negative focal power, a sixth lens with positive focal power, a seventh lens with negative focal power, an eighth lens with positive focal power, a stop, a ninth lens with positive focal power, a tenth lens with negative focal power, an eleventh lens with positive focal power, a twelfth lens with negative focal power, a thirteenth lens with positive focal power, a fourteenth lens with negative focal power, a fifteenth lens with positive focal power, and a sixteenth lens with positive focal power, which are arranged in sequence from the object side to the image side along the optical axis;

[0006] The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the seventh lens and the eighth lens constitute a first lens group having a negative total optical power;

[0007] The ninth lens, the tenth lens, the eleventh lens, the twelfth lens, the thirteenth lens, the fourteenth lens, the fifteenth lens and the sixteenth lens constitute a second lens group having positive total optical power.

[0008] Optionally, the third lens and the sixteenth lens are glass aspherical lenses, and the remaining lenses are glass spherical lenses.

[0009] Optionally, the first lens is a convex-concave lens, the second lens is a convex-concave lens, the third lens is a convex-concave lens, the fourth lens is a convex-convex lens, the fifth lens is a concave-concave lens, the sixth lens is a convex-convex lens, the seventh lens is a concave-convex lens, the eighth lens is a convex-concave lens, the ninth lens is a convex-convex lens, the tenth lens is a concave-concave lens, the eleventh lens is a convex-convex lens, the twelfth lens is a convex-concave lens, the thirteenth lens is a convex-convex lens, the fourteenth lens is a concave-concave lens, the fifteenth lens is a convex-convex lens with positive optical power, and the sixteenth lens is a concave-convex lens.

[0010] Optionally, the fourth lens and the fifth lens form a cemented lens group with negative optical power, and / or the tenth lens and the eleventh lens form a cemented lens group with negative optical power, and / or the twelfth lens and the thirteenth lens can form a cemented lens group with positive optical power.

[0011] Optionally, the first lens, the third lens and the eighth lens respectively meet the following conditions with the full-frame camera lens:

[0012] -5.821≤f1 / f≤-5.444;

[0013] -2.086≤f3 / f≤-1.813;

[0014] -4.763≤f8 / f≤-2.929;

[0015] Among them, f1, f3, f8 are the focal lengths of the first lens, the third lens and the eighth lens respectively, and f is the focal length of the full-frame camera lens.

[0016] Optionally, the first lens group and the second lens group satisfy the following conditions:

[0017]

[0018] in, and are the optical powers of the first lens group and the second lens group respectively.

[0019] Optionally, the full-frame camera lens meets the following conditions:

[0020] 0.135≤f / w≤0.152;

[0021] Wherein, f is the focal length of the full-frame camera lens, and w is the half field of view angle of the full-frame camera lens.

[0022] Optionally, the first lens, the second lens and the fifteenth lens satisfy the following conditions:

[0023] 1.75≤nd1≤1.93, 32.60≤vd1≤50.90;

[0024] 1.59≤nd13≤1.60, 22.00≤vd13≤69.90;

[0025] 1.55≤nd16≤1.83,40.00≤vd16≤60.30;

[0026] Among them, nd1, nd13, and nd16 are the refractive indices of the first lens, the third lens, and the sixteenth lens respectively; vd1, vd13, and vd16 are the Abbe numbers of the first lens, the third lens, and the sixteenth lens respectively.

[0027] Optionally, the sixth lens and the seventh lens meet the following conditions:

[0028] 100.6≥|Vd12+Vd13|≥40.00;

[0029] 92.60≥|Vd14+Vd15|≥76.20;

[0030] Wherein, Vd12, Vd13, Vd14 and Vd15 are the Abbe numbers of the twelfth lens, the thirteenth lens, the fourteenth lens and the fifteenth lens respectively.

[0031] Optionally, the full-frame camera lens meets the following conditions:

[0032] 0.2062 <BFL / TTL<0.2184;

[0033] Among them, BFL is the back focus of the full-frame camera lens, and TTL is the total optical length of the full-frame camera lens.

[0034] The technical solution of the embodiment of the present invention divides the sixteen lenses of the full-frame camera lens into two lens groups with the aperture as the boundary, and adjusts the optical focal length of the lenses in the two lens groups to adjust the light propagation mode in the system, thereby achieving the purpose of improving image quality. Specifically, the first three lenses are all lenses with negative optical power, which ensures that the light of a large field of view can be quickly gathered into the optical system; the fourth lens, the fifth lens, the sixth lens and the seventh lens, whose optical power is positive and negative respectively, can achieve the effect of smoothing the light, and the eighth lens with positive optical power is responsible for continuing to shrink the light; after passing through the aperture and the ninth lens, the tenth lens, the eleventh lens, the twelfth lens and the thirteenth lens can better correct the chromatic aberration of the light after passing through the aperture; the tenth lens to the fifteenth lens can better correct the field curvature under a large field of view by reasonably allocating the optical power, for example, the tenth lens and the eleventh lens form a cemented lens group with negative optical power, the twelfth lens and the thirteenth lens form a cemented lens group with positive optical power, and the fourteenth lens and the fifteenth lens are set to negative and positive optical power, respectively. The sixteenth lens, as the last lens, is responsible for correcting off-axis light and improving the image quality of the edge field of view. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 1 is a schematic structural diagram of an ultra-wide-angle and ultra-short-focus full-frame camera lens provided in Embodiment 1 of the present invention;

[0036] Figure 2 yes Figure 1 The vertical axis chromatic aberration curve of the full-frame camera lens at the optimal object distance is shown;

[0037] Figure 3 yes Figure 1 The field curvature distortion curve of the full-frame camera lens at the optimal object distance is shown;

[0038] Figure 4 yes Figure 1 The resolution MTF curve of the full-frame camera lens at the optimal object distance is shown;

[0039] Figure 5 This is a schematic diagram of the structure of an ultra-wide-angle and ultra-short-focus full-frame camera lens provided in Embodiment 2 of the present invention;

[0040] Figure 6 yes Figure 5 The vertical axis chromatic aberration curve of the full-frame camera lens at the optimal object distance is shown;

[0041] Figure 7 yes Figure 5 The field curvature distortion curve of the full-frame camera lens at the optimal object distance is shown;

[0042] Figure 8 yes Figure 5 The resolution MTF curve of the full-frame camera lens at the optimal object distance is shown;

[0043] Fig. 9 This is a schematic structural diagram of an ultra-wide-angle and ultra-short-focus full-frame camera lens provided in Embodiment 3 of the present invention;

[0044] Fig.10 yes Fig. 9 The vertical axis chromatic aberration curve of the full-frame camera lens at the optimal object distance is shown;

[0045] Fig.11 yes Fig. 9 The field curvature distortion curve of the full-frame camera lens at the optimal object distance is shown;

[0046] Fig.12 yes Fig. 9 The resolution MTF curve of the full-frame camera lens at the optimal object distance is shown. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0048] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. It should be noted that the directional words such as "upper", "lower", "left", "right" and the like described in the embodiments of the present invention are described at the angles shown in the accompanying drawings and should not be understood as limitations on the embodiments of the present invention. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is formed "on" or "under" another element, it can not only be directly formed "on" or "under" another element, but also indirectly formed "on" or "under" another element through an intermediate element. The terms "first", "second", etc. are only used for descriptive purposes and do not represent any order, quantity or importance, but are only used to distinguish different components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific circumstances.

[0049] The term “including” and its variations used in the present invention are open inclusions, that is, “including but not limited to.” The term “based on” means “based at least in part on.” The term “one embodiment” means “at least one embodiment.”

[0050] It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish the corresponding contents, and are not used to limit the order or interdependence.

[0051] It should be noted that the modifications of "one" and "plurality" mentioned in the present invention are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0052] Figure 1 is a schematic diagram of the structure of an ultra-wide-angle and ultra-short-focus full-frame camera lens provided in Embodiment 1 of the present invention, with reference to Figure 1 , the full-frame camera lens comprises a first lens L1 with negative focal power, a second lens L2 with negative focal power, a third lens L3 with negative focal power, a fourth lens L4 with positive focal power, a fifth lens L5 with negative focal power, a sixth lens L6 with positive focal power, a seventh lens L7 with negative focal power, an eighth lens L8 with positive focal power, an aperture STO, a ninth lens L9 with positive focal power, a tenth lens L10 with negative focal power, an eleventh lens L11 with positive focal power, a twelfth lens L12 with negative focal power, a thirteenth lens L13 with positive focal power, a fourteenth lens L14 with negative focal power, a fifteenth lens L15 with positive focal power and a sixteenth lens L16 with positive focal power, which are arranged in sequence from the object side to the image side along the optical axis;

[0053] The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the seventh lens L7 and the eighth lens L8 constitute a first lens group having a negative total optical power;

[0054] The ninth lens L9, the tenth lens L10, the eleventh lens L11, the twelfth lens L12, the thirteenth lens L13, the fourteenth lens L14, the fifteenth lens L15 and the sixteenth lens L16 constitute a second lens group having positive total refractive power.

[0055] First of all, for optical lenses, the focal length is equal to the difference between the convergence of the image-side beam and the convergence of the object-side beam, which characterizes the ability of the optical system to deflect light. The larger the absolute value of the focal length, the stronger the ability to bend light, and the smaller the absolute value of the focal length, the weaker the ability to bend light. When the focal length is a positive number, the refraction of light is convergent; when the focal length is a negative number, the refraction of light is divergent. The focal length can be used to characterize a refractive surface of a lens (i.e., a surface of a lens), can be used to characterize a lens, and can also be used to characterize a system formed by multiple lenses (i.e., a lens group).

[0056] In the full-frame camera lens provided in this embodiment, each lens can be arranged in a lens barrel ( Figure 1 (not shown) in the Figure 1As shown, in the embodiment of the present invention, the sixteen lenses of the full-frame camera lens are divided into two lens groups with the aperture STO as the boundary. By adjusting the optical focal length of the lenses in the two lens groups, the light propagation mode in the system is adjusted to achieve the purpose of improving image quality. Specifically, the first three lenses are lenses with negative optical focal length, which ensures that the light of a large field of view is quickly gathered into the optical system; the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7, whose optical focal lengths are positive, negative, positive and negative respectively, can achieve the effect of smoothing the light, and the eighth lens L8 with positive optical focal length is responsible for continuing to shrink the light; after passing through the aperture STO and the ninth lens L9, the tenth lens L10, the eleventh lens L11, the twelfth lens L12 and the thirteenth lens L13 can better correct the light passing through the aperture Chromatic aberration of light after STO; the tenth lens L10 to the fifteenth lens L15 can better correct the field curvature under a large field of view by reasonably distributing the optical power. For example, the tenth lens L10 and the eleventh lens L11 form a cemented lens group with negative optical power, the twelfth lens L12 and the thirteenth lens L13 form a cemented lens group with positive optical power, and the fourteenth lens L14 and the fifteenth lens L15 are set to negative and positive optical power. The sixteenth lens L16, as the last lens, is responsible for correcting off-axis light and improving the image quality of the marginal field of view.

[0057] In addition, those skilled in the art will know that the aperture STO is used to limit the light beam size in the optical system, and determines the amount of light that enters the photosensitive element through the lens, that is, it is used to control the light throughput of the lens, that is, the aperture STO directly determines the size of the aperture of the optical lens. Setting the aperture STO between the first lens group and the second lens group essentially limits the specific position of the aperture STO at the waist of the entire optical system, thereby accurately controlling the light throughput, expanding the light height of the central main light at the position of the aperture STO, expanding the aperture, ensuring the amount of light passing through the aperture STO, and ensuring the brightness of the image; in addition, the aperture STO can block the light of the far axis, effectively reduce the off-axis aberration, and ensure the clarity of the image. Therefore, the embodiment of the present invention can achieve a full field of view angle ≥ 132°, while also having smaller distortion and improving the purple fringing phenomenon.

[0058] In a specific embodiment, optionally, the third lens L3 and the sixteenth lens L16 are glass aspherical lenses, and the remaining lenses are glass spherical lenses.

[0059] In this embodiment, the full-frame camera lens actually uses an optical structure of 14 glass spherical lenses and 2 glass aspherical lenses to achieve an all-glass fixed-focus lens. The sixteenth lens L16 is the last lens and is an aspherical lens, which can better correct off-axis light and improve the image quality of the edge field of view. By adding aspherical lenses, the image quality of the edge field of view can be significantly improved at ultra-short focal lengths, and clear imaging and almost zero distortion shooting experience can be achieved.

[0060] In a specific embodiment, optionally, the first lens L1 is a convex-concave lens, the second lens L2 is a convex-concave lens, the third lens L3 is a convex-concave lens, the fourth lens L4 is a convex-convex lens, the fifth lens L5 is a concave-concave lens, the sixth lens L6 is a convex-convex lens, the seventh lens L7 is a concave-convex lens, the eighth lens L8 is a convex-concave lens, the ninth lens L9 is a convex-convex lens, the tenth lens L10 is a concave-concave lens, the eleventh lens L11 is a convex-convex lens, the twelfth lens L12 is a convex-concave lens, the thirteenth lens L13 is a convex-convex lens, the fourteenth lens L14 is a concave-concave lens, the fifteenth lens L15 is a convex-convex lens with positive optical power, and the sixteenth lens L16 is a concave-convex lens.

[0061] In a specific embodiment, optionally, the fourth lens L4 and the fifth lens L5 form a cemented lens group with negative optical power, and / or the tenth lens L10 and the eleventh lens L11 form a cemented lens group with negative optical power, and / or the twelfth lens L12 and the thirteenth lens L13 can form a cemented lens group with positive optical power.

[0062] In this embodiment, the surfaces of adjacent partial lenses are glued together to form a glued lens group, which can reduce the distance between lenses, and at the same time can properly correct chromatic aberration, improve field curvature and coma, thereby further optimizing the imaging quality.

[0063] In a specific embodiment, optionally, the first lens L1, the third lens L3 and the eighth lens L8 respectively meet the following conditions with the full-frame camera lens:

[0064] -5.821≤f1 / f≤-5.444;

[0065] -2.086≤f3 / f≤-1.813;

[0066] -4.763≤f8 / f≤-2.929;

[0067] Among them, f1, f3, f8 are the focal lengths of the first lens L1, the third lens L3 and the eighth lens L8 respectively, and f is the focal length of the full-frame camera lens.

[0068] Those skilled in the art will know that the focal length is the inverse of the optical power. By reasonably allocating the optical power of each lens, the light of the entire optical system can pass through the lens more reasonably, reduce the spherical aberration and field curvature of the lens, and ensure the image quality of the on-axis and off-axis fields of view. When the first lens L1, the third lens L3 and the eighth lens L8 respectively meet the above conditions with the full-frame camera lens, the lens is divergent, which is conducive to converging light at a larger angle and meeting a larger detection range; at the same time, it is conducive to ensuring the system tolerance balance and reducing assembly sensitivity.

[0069] In a specific embodiment, optionally, the first lens group and the second lens group satisfy the following conditions:

[0070]

[0071] in, and are the optical powers of the first lens group and the second lens group respectively.

[0072] In this embodiment, the first lens group is provided with The focal length range is used to quickly collect large-angle light, and convert the large-angle incident angle into a smaller angle through the aperture STO and enter the second lens group. The second lens group has The focal length range is conducive to suppressing the angle of the edge field of view incident on the imaging surface, effectively transmitting more light beams to the imaging surface, so as to match the chip CRA curve requirements. In addition, the aperture STO is located in the middle of the lens, the first lens group is in front of the aperture STO, and the second lens group is behind the aperture STO. When the focal length of the two lens groups meets When the lens is arranged symmetrically, it helps to reduce distortion.

[0073] In a specific embodiment, optionally, the full-frame camera lens satisfies the following conditions:

[0074] 0.135≤f / w≤0.152;

[0075] Among them, f is the focal length of the full-frame camera lens, and w is the half field of view angle of the full-frame camera lens.

[0076] In this embodiment, since the focal length required for the full-frame camera lens is shorter and the field of view angle is larger, under the above conditions, clear imaging can still be achieved at a larger angle field of view, the depth of field is shallower, and the lens can be more compact.

[0077] In a specific embodiment, optionally, the first lens L1, the second lens L2 and the fifteenth lens L15 satisfy the following conditions:

[0078] 1.75≤nd1≤1.93, 32.60≤vd1≤50.90;

[0079] 1.59≤nd13≤1.60, 22.00≤vd13≤69.90;

[0080] 1.55≤nd16≤1.83,40.00≤vd16≤60.30;

[0081] Wherein, nd1, nd13, and nd16 are the refractive indices of the first lens L1, the third lens L3, and the sixteenth lens L16, respectively; vd1, vd13, and vd16 are the Abbe numbers of the first lens L1, the third lens L3, and the sixteenth lens L16, respectively.

[0082] In this embodiment, since the field of view required by the full-frame camera lens is relatively large, when the first lens L1, as a convex-concave lens with negative focal power, satisfies the range of 1.75≤nd1≤1.93, it can quickly gather light and share the aberration pressure of the large field of view, and at the same time effectively compress the overall lens aperture of the lens to achieve miniaturization of the lens; when the thirteenth lens L13, as a positive lens, satisfies 22.00≤vd13≤69.90, it can effectively control axial chromatic aberration when matched with the twelfth lens L12; when the sixteenth lens L16, as a negative lens, satisfies 1.55≤nd16≤1.83 and 40.00≤vd16≤60.30, it can effectively improve the image quality of the last lens in the marginal market where the image is incident at a large angle to the image plane.

[0083] In a specific embodiment, optionally, the sixth lens L6 and the seventh lens L7 satisfy the following conditions:

[0084] 100.6≥|Vd12+Vd13|≥40.00;

[0085] 92.60≥|Vd14+Vd15|≥76.20;

[0086] Among them, Vd12, Vd13, Vd14 and Vd15 are the Abbe numbers of the twelfth lens L12, the thirteenth lens L13, the fourteenth lens L14 and the fifteenth lens L15 respectively.

[0087] When the sixth lens L6 and the seventh lens L7 meet the above conditions, the spherical aberration and off-axis aberration generated after the light passes through the first lens group can be effectively controlled, and the chromatic aberration can be minimized when the light enters the aperture STO with a large change in the folding angle, so as to balance some off-axis chromatic aberration.

[0088] In a specific embodiment, optionally, the full-frame camera lens satisfies the following conditions:

[0089] 0.2062 <BFL / TTL<0.2184;

[0090] Among them, BFL is the back focus of the full-frame camera lens, and TTL is the total optical length of the full-frame camera lens.

[0091] In this embodiment, by reasonably selecting the back focus and total length of the lens, the lens can ensure that there is sufficient installation space for the imaging sensor and the flat filter, ensure that the lens will not interfere with the base and the housing when installed, and ensure that the equipment process of the ultra-wide-angle lens is simple.

[0092] Based on the same concept above, the present invention provides three different specific embodiments, and the optical power relationship and related physical optical parameter design ranges thereof are shown in Table 1:

[0093] Table 1 Relationship between optical power and related physical optical parameters in various embodiments

[0094]

[0095]

[0096] In the first embodiment of the present invention, reference Figure 1 It can be seen that the structural composition of each component of the system and the shape and position of each component are crucial to the system. It can be seen from the figure that the optical system is composed of 16 optical lenses, among which the aperture STO is located on the side of the image of the eighth lens L8. A plane glass L17 is also provided along the object plane to the image plane; the plane glass L17 is located on the image side of the sixteenth lens L16, and the plane glass L17 can protect the photosensitive chip in the imaging sensor to ensure the imaging effect of the fixed focus lens. The overall layout of the system is that the eight lenses before the aperture STO constitute the first lens group, among which the fourth lens L4 and the fifth lens L5 are glued, and the sixth lens L6 and the seventh lens L7 are glued; the eight lenses after the aperture STO constitute the second lens group, among which the tenth lens L10 and the eleventh lens L11 are glued, and the twelfth lens L12 and the thirteenth lens L13 are glued.

[0097] like Figure 1 The parameter design values ​​of each lens in the full-frame camera lens of the first embodiment are shown in Table 2:

[0098] Table 2: Design values ​​of each lens of the full-frame camera lens in Example 1

[0099]

[0100]

[0101]

[0102] The surface numbers in Table 2 are numbered according to the order of the surfaces of each lens; the radius of curvature represents the curvature of the lens surface, a positive value represents that the surface is curved toward the image plane, and a negative value represents that the surface is curved toward the object plane; "INF" indicates that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, the refractive index represents the ability of the material between the current surface and the next surface to deflect light, and the space represents that the current position is air with a refractive index of 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface to the light. The semi-aperture represents half of the aperture size of the current surface.

[0103] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0104]

[0105] Where Z is the axial distance from the surface at a height r perpendicular to the optical axis to the vertex of the surface along the optical axis; c represents the curvature at the vertex of the aspheric surface; k is the fitting cone coefficient; a 4 、a 6 、a 8 、a 10 、a 12 is the high-order aspheric coefficient corresponding to the fourth, sixth, eighth, tenth, and twelfth order of the aspheric surface, a i r i The combination becomes the high-order terms corresponding to the aspherical surface.

[0106] The coefficient values ​​of each aspheric surface in the above embodiment 1 are shown in Table 3:

[0107] Table 3 Aspheric surface parameters

[0108]

[0109]

[0110] Among them, 4.959805402E-05 represents the coefficient a of the surface number S5 4 is 4.959805402*10 -5 , and so on.

[0111] Figure 2 yes Figure 1 The vertical axis chromatic aberration curve of the full-frame camera lens at the optimal object distance is shown, where the vertical direction is the field of view, 0 represents the optical axis, and the vertical vertex represents the maximum half field of view; the horizontal direction represents the offset relative to the main wavelength, in microns (um). If the vertical axis chromatic aberration is too large, it will cause the object image to disperse and affect the image clarity. Figure 2 It can be seen that the vertical chromatic aberrations of different wavelengths are all controlled within a reasonable range, are all relatively close to the main light, and are basically within the Airy disk, which significantly improves the common purple fringing phenomenon.

[0112] Figure 3 yes Figure 1 The field curvature distortion curve of the full-frame camera lens at the optimal object distance is shown in the figure. In the coordinate system on the right side of the figure, the horizontal coordinate represents the size of the distortion, the unit is %; the vertical coordinate represents the normalized image height, there is no unit; Figure 3It can be seen that the distortion of the lens provided in this embodiment is well corrected, which better ensures the authenticity of the object imaging and has small imaging distortion. In the left coordinate system of the figure, the horizontal coordinate represents the magnitude of the field curvature, in units of mm; the vertical coordinate represents the normalized image height, without units; T represents the meridian, S represents the sagittal; Figure 3 It can be seen that the resolution difference between the center of the field curvature of the lens provided in this embodiment and that near the edge of the field of view is relatively small.

[0113] Figure 4 yes Figure 1 The MTF curve of the resolution of the full-frame camera lens at the optimal object distance is shown in the figure. The horizontal axis is the spatial frequency, which refers to the number of black and white line pairs / 1mm. The vertical axis is the modulation modulus (M' / M), where M refers to the grating modulation before imaging and M' refers to the grating modulation after imaging, so 0≤M' / M≤1. The MTF curve shows the resolution of the optical system for objects at different frequencies in different fields of view, meridian and sagittal directions, and reflects the degree of imaging of the image quality of the object after passing through the optical system. The higher the MTF, the higher the imaging quality of the lens. Figure 4 It can be seen that the MTF of the optical system in all meridian and sagittal directions of the field of view is greater than 0.4 when the spatial frequency is 40lp / mm, which has a very high imaging effect for SLR cameras.

[0114] Figure 5 is a schematic structural diagram of an ultra-wide-angle and ultra-short-focus full-frame camera lens provided in Embodiment 2 of the present invention. In Embodiment 2 of the present invention, reference is made to Figure 5 It can be seen that the structural composition of each component of the system and the shape and position of each component are crucial to the system. It can be seen from the figure that the optical system is composed of 16 optical lenses, among which the aperture STO is located on the side of the image of the eighth lens L8. A plane glass L17 is also provided along the object plane to the image plane; the plane glass L17 is located on the image side of the sixteenth lens L16, and the plane glass L17 can protect the photosensitive chip in the imaging sensor to ensure the imaging effect of the fixed focus lens. The overall layout of the system is that the eight lenses before the aperture STO constitute the first lens group, among which the fourth lens L4 and the fifth lens L5 are glued, and the sixth lens L6 and the seventh lens L7 are glued; the eight lenses after the aperture STO constitute the second lens group, among which the tenth lens L10 and the eleventh lens L11 are glued, and the twelfth lens L12 and the thirteenth lens L13 are glued.

[0115] like Figure 5 The parameter design values ​​of each lens in the full-frame camera lens of the second embodiment are shown in Table 4:

[0116] Table 4: Design values ​​of each lens of the full-frame camera lens in Example 2

[0117]

[0118]

[0119]

[0120] The surface numbers in Table 4 are numbered according to the order of the surfaces of each lens; the radius of curvature represents the curvature of the lens surface, a positive value represents that the surface is curved toward the image plane, and a negative value represents that the surface is curved toward the object plane; "INF" indicates that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, the refractive index represents the ability of the material between the current surface and the next surface to deflect light, and the space represents that the current position is air with a refractive index of 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface to the light. The semi-aperture represents half of the aperture size of the current surface.

[0121] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0122]

[0123] Where Z is the axial distance from the surface at a height r perpendicular to the optical axis to the vertex of the surface along the optical axis; c represents the curvature at the vertex of the aspheric surface; k is the fitting cone coefficient; a 4 、a 6 、a 8 、a 10 、a 12 is the high-order aspheric coefficient corresponding to the fourth, sixth, eighth, tenth, and twelfth order of the aspheric surface, a i r i The combination becomes the high-order terms corresponding to the aspherical surface.

[0124] The coefficient values ​​of each aspheric surface in the above-mentioned embodiment 2 are shown in Table 5:

[0125] Table 5 Aspheric surface parameters

[0126]

[0127]

[0128] Among them, 5.012216780E-05 represents the coefficient a of the surface number S5 4 is 5.012216780*10 -5 , and so on.

[0129] Figure 6 yes Figure 5The vertical axis chromatic aberration curve of the full-frame camera lens at the optimal object distance is shown, where the vertical direction is the field of view, 0 represents the optical axis, and the vertical vertex represents the maximum half field of view; the horizontal direction represents the offset relative to the main wavelength, in microns (um). If the vertical axis chromatic aberration is too large, it will cause the object image to disperse and affect the image clarity. Figure 6 It can be seen that the vertical chromatic aberrations of different wavelengths are all controlled within a reasonable range, are all relatively close to the main light, and are basically within the Airy disk, which significantly improves the common purple fringing phenomenon.

[0130] Figure 7 yes Figure 5 The field curvature distortion curve of the full-frame camera lens at the optimal object distance is shown in the figure. In the coordinate system on the right side of the figure, the horizontal coordinate represents the size of the distortion, the unit is %; the vertical coordinate represents the normalized image height, there is no unit; Figure 7 It can be seen that the distortion of the lens provided in this embodiment is well corrected, which better ensures the authenticity of the object imaging and has small imaging distortion. In the left coordinate system of the figure, the horizontal coordinate represents the magnitude of the field curvature, in units of mm; the vertical coordinate represents the normalized image height, without units; T represents the meridian, S represents the sagittal; Figure 7 It can be seen that the resolution difference between the center of the field curvature of the lens provided in this embodiment and that near the edge of the field of view is relatively small.

[0131] Figure 8 yes Figure 5 The MTF curve of the resolution of the full-frame camera lens at the optimal object distance is shown in the figure. The horizontal axis is the spatial frequency, which refers to the number of black and white line pairs / 1mm. The vertical axis is the modulation modulus (M' / M), where M refers to the grating modulation before imaging and M' refers to the grating modulation after imaging, so 0≤M' / M≤1. The MTF curve shows the resolution of the optical system for objects at different frequencies in different fields of view, meridian and sagittal directions, and reflects the degree of imaging of the image quality of the object after passing through the optical system. The higher the MTF, the higher the imaging quality of the lens. Figure 8 It can be seen that the MTF of the optical system in all meridian and sagittal directions of the field of view is greater than 0.4 when the spatial frequency is 40lp / mm, which has a very high imaging effect for SLR cameras.

[0132] Fig. 9 is a schematic diagram of the structure of an ultra-wide-angle and ultra-short-focus full-frame camera lens provided in Embodiment 3 of the present invention. In Embodiment 3 of the present invention, reference is made to Fig. 9It can be seen that the structural composition of each component of the system and the shape and position of each component are crucial to the system. It can be seen from the figure that the optical system is composed of 16 optical lenses, among which the aperture STO is located on the side of the image of the eighth lens L8. A plane glass L17 is also provided along the object plane to the image plane; the plane glass L17 is located on the image side of the sixteenth lens L16, and the plane glass L17 can protect the photosensitive chip in the imaging sensor to ensure the imaging effect of the fixed focus lens. The overall layout of the system is that the eight lenses before the aperture STO constitute the first lens group, among which the fourth lens L4 and the fifth lens L5 are glued, and the sixth lens L6 and the seventh lens L7 are glued; the eight lenses after the aperture STO constitute the second lens group, among which the tenth lens L10 and the eleventh lens L11 are glued, and the twelfth lens L12 and the thirteenth lens L13 are glued.

[0133] like Fig. 9 The parameter design values ​​of each lens in the full-frame camera lens of the third embodiment are shown in Table 6:

[0134] Table 6: Design values ​​of each lens of the full-frame camera lens in Example 3

[0135]

[0136]

[0137]

[0138] The surface numbers in Table 6 are numbered according to the order of the surfaces of each lens; the radius of curvature represents the curvature of the lens surface, a positive value represents that the surface is curved toward the image plane, and a negative value represents that the surface is curved toward the object plane; "INF" indicates that the surface is a plane and the radius of curvature is infinite; the thickness represents the central axial distance from the current surface to the next surface, the refractive index represents the ability of the material between the current surface and the next surface to deflect light, and the space represents that the current position is air with a refractive index of 1; the Abbe number represents the dispersion characteristics of the material between the current surface and the next surface to the light. The semi-aperture represents half of the aperture size of the current surface.

[0139] The aspheric cone coefficient can be defined by the following aspheric formula, but is not limited to the following representation method:

[0140]

[0141] Where Z is the axial distance from the surface at a height r perpendicular to the optical axis to the vertex of the surface along the optical axis; c represents the curvature at the vertex of the aspheric surface; k is the fitting cone coefficient; a 4 、a 6 、a 8 、a 10 、a 12is the high-order aspheric coefficient corresponding to the fourth, sixth, eighth, tenth, and twelfth order of the aspheric surface, a i r i The combination becomes the high-order terms corresponding to the aspherical surface.

[0142] The coefficient values ​​of each aspheric surface in the above-mentioned embodiment 3 are shown in Table 7:

[0143] Table 7 Aspheric surface parameters

[0144]

[0145]

[0146] Among them, 5.440978483E-05 represents the coefficient a of the surface number S5 4 is 5.440978483*10 -5 , and so on.

[0147] Fig.10 yes Fig. 9 The vertical axis chromatic aberration curve of the full-frame camera lens at the optimal object distance is shown, where the vertical direction is the field of view, 0 represents the optical axis, and the vertical vertex represents the maximum half field of view; the horizontal direction represents the offset relative to the main wavelength, in microns (um). If the vertical axis chromatic aberration is too large, it will cause the object image to disperse and affect the image clarity. Fig.10 It can be seen that the vertical chromatic aberrations of different wavelengths are all controlled within a reasonable range, are all relatively close to the main light, and are basically within the Airy disk, which significantly improves the common purple fringing phenomenon.

[0148] Fig.11 yes Fig. 9 The field curvature distortion curve of the full-frame camera lens at the optimal object distance is shown in the figure. In the coordinate system on the right side of the figure, the horizontal coordinate represents the size of the distortion, the unit is %; the vertical coordinate represents the normalized image height, there is no unit; Fig.11 It can be seen that the distortion of the lens provided in this embodiment is well corrected, which better ensures the authenticity of the object imaging and has small imaging distortion. In the left coordinate system of the figure, the horizontal coordinate represents the magnitude of the field curvature, in units of mm; the vertical coordinate represents the normalized image height, without units; T represents the meridian, S represents the sagittal; Fig.11 It can be seen that the resolution difference between the center of the field curvature of the lens provided in this embodiment and that near the edge of the field of view is relatively small.

[0149] Fig.12 yes Fig. 9The MTF curve of the resolution of the full-frame camera lens at the optimal object distance is shown in the figure. The horizontal axis is the spatial frequency, which refers to the number of black and white line pairs / 1mm. The vertical axis is the modulation modulus (M' / M), where M refers to the grating modulation before imaging and M' refers to the grating modulation after imaging, so 0≤M' / M≤1. The MTF curve shows the resolution of the optical system for objects at different frequencies in different fields of view, meridian and sagittal directions, and reflects the degree of imaging of the image quality of the object after passing through the optical system. The higher the MTF, the higher the imaging quality of the lens. Fig.12 It can be seen that the MTF of the optical system in all meridian and sagittal directions of the field of view is greater than 0.4 when the spatial frequency is 40lp / mm, which has a very high imaging effect for SLR cameras.

[0150] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An ultra-wide-angle and ultra-short-focus full-frame camera lens, characterized in that: The optical lens comprises a first lens with negative power, a second lens with negative power, a third lens with negative power, a fourth lens with positive power, a fifth lens with negative power, a sixth lens with positive power, a seventh lens with negative power, an eighth lens with positive power, a stop, a ninth lens with positive power, a tenth lens with negative power, an eleventh lens with positive power, a twelfth lens with negative power, a thirteenth lens with positive power, a fourteenth lens with negative power, a fifteenth lens with positive power and a sixteenth lens with positive power, which are arranged in sequence from the object side to the image side along the optical axis; The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the seventh lens and the eighth lens constitute a first lens group having a negative total optical power; The ninth lens, the tenth lens, the eleventh lens, the twelfth lens, the thirteenth lens, the fourteenth lens, the fifteenth lens and the sixteenth lens constitute a second lens group having positive total optical power.

2. The full-frame camera lens according to claim 1, characterized in that: The third lens and the sixteenth lens are glass aspherical lenses, and the remaining lenses are glass spherical lenses.

3. The full-frame camera lens according to claim 1, characterized in that: The first lens is a convex-concave lens, the second lens is a convex-concave lens, the third lens is a convex-concave lens, the fourth lens is a convex-convex lens, the fifth lens is a concave-concave lens, the sixth lens is a convex-convex lens, the seventh lens is a concave-convex lens, the eighth lens is a convex-concave lens, the ninth lens is a convex-convex lens, the tenth lens is a concave-concave lens, the eleventh lens is a convex-convex lens, the twelfth lens is a convex-concave lens, the thirteenth lens is a convex-convex lens, the fourteenth lens is a concave-concave lens, the fifteenth lens is a convex-convex lens with positive optical power, and the sixteenth lens is a concave-convex lens.

4. The full-frame camera lens according to claim 1, characterized in that: The fourth lens and the fifth lens form a cemented lens group with negative optical power, and / or the tenth lens and the eleventh lens form a cemented lens group with negative optical power, and / or the twelfth lens and the thirteenth lens can form a cemented lens group with positive optical power.

5. The full-frame camera lens according to claim 1, characterized in that: The first lens, the third lens and the eighth lens respectively meet the following conditions with the full-frame camera lens: -5.821≤f1 / f≤-5.444; -2.086≤f3 / f≤-1.813; -4.763≤f8 / f≤-2.929; Among them, f1, f3, f8 are the focal lengths of the first lens, the third lens and the eighth lens respectively, and f is the focal length of the full-frame camera lens.

6. The full-frame camera lens according to claim 1, characterized in that: The first lens group and the second lens group satisfy the following conditions: -0.0250<φ1<0.0025; 0.0330<φ2<0.0379; -0.6605<(φ1 / φ2)<-0.0758; Wherein, φ1 and φ2 are the optical powers of the first lens group and the second lens group respectively.

7. The full-frame camera lens according to claim 1, characterized in that: The full-frame camera lens meets the following conditions: 0.135≤f / w≤0.152; Wherein, f is the focal length of the full-frame camera lens, and w is the half field of view angle of the full-frame camera lens.

8. The full-frame camera lens according to claim 1, characterized in that: The first lens, the second lens and the fifteenth lens meet the following conditions: 1.75≤nd1≤1.93, 32.60≤vd1≤50.90; 1.59≤nd13≤1.60, 22.00≤vd13≤69.90; 1.55≤nd16≤1.83,40.00≤vd16≤60.30; Among them, nd1, nd13, and nd16 are the refractive indices of the first lens, the third lens, and the sixteenth lens respectively; vd1, vd13, and vd16 are the Abbe numbers of the first lens, the third lens, and the sixteenth lens respectively.

9. The full-frame camera lens according to claim 1, characterized in that: The sixth lens and the seventh lens meet the following conditions: 100.6≥|Vd12+Vd13|≥40.00; 92.60≥|Vd14+Vd15|≥76.20; Wherein, Vd12, Vd13, Vd14 and Vd15 are the Abbe numbers of the twelfth lens, the thirteenth lens, the fourteenth lens and the fifteenth lens respectively.

10. The full-frame camera lens according to claim 1, characterized in that: The full-frame camera lens meets the following conditions: 0.2062 <BFL / TTL<0.2184; Among them, BFL is the back focus of the full-frame camera lens, and TTL is the total optical length of the full-frame camera lens.

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