WO2021142628A1 - 光学成像系统、取像装置及电子装置 - Google Patents

光学成像系统、取像装置及电子装置 Download PDF

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Publication number
WO2021142628A1
WO2021142628A1 PCT/CN2020/072054 CN2020072054W WO2021142628A1 WO 2021142628 A1 WO2021142628 A1 WO 2021142628A1 CN 2020072054 W CN2020072054 W CN 2020072054W WO 2021142628 A1 WO2021142628 A1 WO 2021142628A1
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Prior art keywords
lens
imaging system
optical imaging
image side
optical axis
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PCT/CN2020/072054
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English (en)
French (fr)
Inventor
邹金华
刘彬彬
谢晗
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南昌欧菲精密光学制品有限公司
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Priority to PCT/CN2020/072054 priority Critical patent/WO2021142628A1/zh
Publication of WO2021142628A1 publication Critical patent/WO2021142628A1/zh

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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00—Optical objectives specially designed for the purposes specified below
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00—Optical objectives specially designed for the purposes specified below
    • G02B13/18—Optical objectives specially designed for the purposes specified below with lenses having one or more non-spherical faces, e.g. for reducing geometrical aberration
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B9/00—Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or -
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B9/00—Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or -
    • G02B9/64—Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or - having more than six components

Definitions

  • This application relates to the field of optical imaging technology, and in particular to an optical imaging system, imaging device and electronic device suitable for infrared light imaging.
  • TOF Time of Flight
  • the application fields of TOF lenses have become very extensive, including face unlocking of mobile devices, automatic driving of cars, man-machine interfaces and Games, industrial machine vision and measurement, security monitoring, etc.
  • the TOF lens is used to receive the light emitted by the TOF emitting end reflected by the subject. It is different from the ordinary optical lens in that an infrared bandpass filter is required to ensure that only the light with the same wavelength as the light source at the emitting end can be captured by the photosensitive element. .
  • the TOF lens can not only record the depth information of the subject to form an image, but also can perform different blurring intensities for scenes and people of different depths, thereby greatly improving the shooting effect.
  • an optical imaging system is provided.
  • An optical imaging system for infrared light imaging which includes a first lens with refractive power in sequence from the object side to the image side along the optical axis; a second lens with refractive power; and a positive refractive power Powerful third lens, the image side of the third lens is convex at the circumference; the fourth lens with negative refractive power; the fifth lens with positive refractive power, the image side of the fifth lens is at the optical axis It is a concave surface, the object side surface and the image side surface of the fifth lens are both aspherical, and at least one of the object side surface and the image side surface includes at least one inflection point; the optical imaging system satisfies the following relationship:
  • TT is the distance on the optical axis from the object side of the first lens to the image side of the fifth lens
  • f is the effective focal length of the optical imaging system.
  • An image capturing device includes the optical imaging system described in the above embodiment; and a photosensitive element, the photosensitive element being arranged on the image side of the optical imaging system.
  • An electronic device includes a housing and the imaging device described in the above embodiments, and the imaging device is installed on the housing.
  • Fig. 1 shows a schematic structural diagram of an optical imaging system according to Embodiment 1 of the present application
  • Fig. 2 respectively shows a longitudinal spherical aberration curve, an astigmatism curve and a distortion curve of the optical imaging system of Embodiment 1;
  • FIG. 3 shows a schematic structural diagram of an optical imaging system according to Embodiment 2 of the present application
  • FIG. 5 shows a schematic structural diagram of an optical imaging system according to Embodiment 3 of the present application.
  • Fig. 6 respectively shows a longitudinal spherical aberration curve, an astigmatism curve and a distortion curve of the optical imaging system of Embodiment 3;
  • FIG. 7 shows a schematic structural diagram of an optical imaging system according to Embodiment 4 of the present application.
  • FIG. 8 respectively shows a longitudinal spherical aberration curve diagram, an astigmatism curve diagram, and a distortion curve diagram of the optical imaging system of Embodiment 4;
  • FIG. 9 shows a schematic structural diagram of an optical imaging system according to Embodiment 5 of the present application.
  • FIG. 10 respectively shows a longitudinal spherical aberration curve diagram, an astigmatism curve diagram, and a distortion curve diagram of the optical imaging system of Embodiment 5;
  • FIG. 11 shows a schematic structural diagram of an optical imaging system according to Embodiment 6 of the present application.
  • FIG. 12 shows the longitudinal spherical aberration curve, the astigmatism curve, and the distortion curve of the optical imaging system of Embodiment 6 respectively.
  • first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any restriction on the feature. Therefore, without departing from the teachings of the present application, the first lens discussed below may also be referred to as a second lens or a third lens.
  • the shape of the spherical or aspherical surface shown in the drawings is shown by way of example. That is, the shape of the spherical surface or the aspheric surface is not limited to the shape of the spherical surface or the aspheric surface shown in the drawings.
  • the drawings are only examples and are not drawn strictly to scale.
  • TOF Time of Flight
  • An embodiment of the present application provides a five-chip TOF optical imaging system.
  • the optical imaging system can image infrared light, and while ensuring miniaturization, the imaging resolution is also high. Specifically, it includes a first lens, a second lens, and a lens that are arranged in order from the object side to the image side along the optical axis.
  • the third lens, the fourth lens and the fifth lens, the imaging surface of the optical imaging system is located on the image side of the fifth lens.
  • the first lens and the second lens have refractive power, so that the light emitted from the TOF emitting end reflected by the subject can be captured by the optical imaging system.
  • the third lens has a positive refractive power, and the image side surface of the third lens is convex at the optical axis, which is beneficial to correct the astigmatic aberration of the optical imaging system, thereby improving the imaging quality of the optical imaging system.
  • the fourth lens has a negative refractive power, which is beneficial to correct the chromatic aberration of the optical imaging system, thereby improving the imaging quality of the optical imaging system.
  • the fifth lens has positive refractive power, and the image side surface of the fifth lens is concave at the optical axis, which is beneficial to combine the positive refractive power of the third lens to balance the negative spherical aberration generated by the fourth lens and correct the coma of the optical imaging system ;
  • the object side and image side of the fifth lens are both aspherical, which is beneficial to further correct the aberration of the optical imaging system;
  • at least one of the object side and the image side of the fifth lens contains at least one inflection point, which can effectively suppress The angle at which the light from the off-axis field of view is incident on the photosensitive element makes it more accurately match the photosensitive element, thereby improving the light receiving efficiency of the photosensitive element.
  • the optical imaging system satisfies the following relationship: TT/f ⁇ 1.5; where TT is the distance from the object side of the first lens to the image side of the fifth lens on the optical axis, and f is the effective focal length of the optical imaging system.
  • TT/f can be 1.0, 1.15, 1.20, 1.25, 1.30, 1.35, 1.40, or 1.45.
  • the total length of the optical imaging system can be shortened and the miniaturization of the lens can be ensured, while the light projected by the optical imaging system can be better converged to the imaging surface, thereby enhancing its imaging resolution capability.
  • the infrared light emitted or reflected by the subject enters the optical imaging system from the object side, and passes through the first lens, the second lens, the third lens, the fourth lens, and the fifth lens in sequence.
  • the lens finally converges on the imaging surface.
  • the above-mentioned optical imaging system by reasonably distributing the refractive power, surface shape and effective focal length of each lens, can ensure the miniaturization of the optical imaging system, and enhance the imaging resolution capability of the optical imaging system for infrared light and the low-light shooting capability. .
  • the optical imaging system of the present application can maintain good imaging quality in a wide range of infrared bands, thereby meeting the working requirements of the TOF lens.
  • the object side surface and the image side surface of each lens of the first lens to the fifth lens can be set to be aspherical, thereby improving the flexibility of lens design, effectively correcting aberrations, and improving the optical imaging system The imaging resolution.
  • the object side surface and the image side surface of each lens of the optical imaging system may also be spherical surfaces. It should be noted that the above-mentioned embodiments are only examples of some embodiments of the present application.
  • the surface of each lens in the optical imaging system may be an aspheric surface or any combination of spherical surfaces.
  • an infrared band pass filter is provided between the fifth lens and the imaging surface of the optical imaging system.
  • the wavelength band of the light incident on the imaging surface of the optical imaging system can be selected. For example, only the infrared light from the TOF emitting end reflected by the subject can pass through, so as to ensure that the optical imaging system can meet TOF.
  • a filter film may be provided on the object side or image side of one of the first lens to the fifth lens to achieve the same wavelength selection effect, which is not limited in this application.
  • the optical imaging system satisfies the following relationship:
  • CT1+CT2+CT3 can be 0.8mm, 0.85mm, 0.9mm, 0.95mm, 1.0mm, 1.10mm, 1.20mm, 1.30mm, 1.35mm, or 1.40mm. Under the condition that the above relationship is satisfied, the tolerance of the first lens to the environment can be enhanced, and the thickness of the second lens and the third lens on the optical axis can be configured on this basis, which is conducive to the miniaturization design of the optical imaging system.
  • CT1+CT2+CT3 When CT1+CT2+CT3 is less than or equal to 0.7mm, the lens will be too thin, resulting in low lens strength and low manufacturing yield; when CT1+CT2+CT3 is greater than or equal to 1.6mm, the lens will be too thick and not Conducive to the miniaturization of the optical imaging system.
  • the optical imaging system satisfies the following relationship:
  • T12 is the distance from the image side of the first lens to the object side of the second lens on the optical axis
  • T23 is the distance between the image side of the second lens and the object side of the third lens on the optical axis.
  • the distance on the optical axis, T34 is the distance from the image side of the third lens to the object side of the fourth lens on the optical axis
  • T45 is the distance from the image side of the fourth lens to the object side of the fifth lens on the optical axis.
  • T12+T23+T34+T45 may be 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, or 0.9mm. Under the condition that the above relationship is satisfied, it is beneficial to realize the miniaturization of the optical imaging system and improve the assembly yield of the lens.
  • T12+T23+T34+T45 is less than or equal to 0.25mm, the adjustable space between adjacent lenses will be too small, which is easy to increase the system sensitivity and is not conducive to the assembly of the lens; and when T12+T23+T34 When +T45 is greater than or equal to 0.95mm, it is not conducive to miniaturization and ultra-thinness of the optical imaging system.
  • the optical imaging system satisfies the following relationship: 0.5 ⁇ f3/f5 ⁇ 3.5; where f3 is the effective focal length of the third lens, and f5 is the effective focal length of the fifth lens.
  • f3/f5 can be 0.6, 0.7, 0.75, 0.85, 0.95, 1.2, 1.25, 2.0, 2.5, 3.0, 3.1, or 3.2.
  • the third lens needs to provide most of the positive refractive power, which causes the object side of the third lens to be excessively bent and poorly formed, which affects the manufacturing yield of the lens; and when f3/ When f5 is greater than or equal to 3.5, the refractive power distribution of the second lens and the fourth lens is likely to be unbalanced, which makes the aberration of the optical imaging system too large, which is not conducive to aberration correction.
  • the optical imaging system satisfies the following relationship: FNO ⁇ 1.3; where FNO is the number of apertures of the optical imaging system.
  • the FNO can be 1.1, 1.13, 1.16, 1.19, 1.22, 1.25, 1.28, or 1.29.
  • FNO ⁇ 1.1 Preferably, FNO ⁇ 1.1.
  • the optical imaging system satisfies the following relationship: 1.4 ⁇ nd1 ⁇ 1.7; 1.4 ⁇ nd2 ⁇ 1.7; 1.4 ⁇ nd4 ⁇ 1.7; where nd1 is the refractive index of the first lens, and nd2 is the refractive index of the second lens
  • the refractive index, nd4 is the refractive index of the fourth lens.
  • nd1, nd2, and nd4 can all be 1.5, 1.54, 1.545, 1.546, 1.548, 1.550, 1.6, 1.64, or 1.66.
  • the optical imaging system satisfies the following relationship: 0.85 ⁇ SD32/SD11 ⁇ 1.3; where SD32 is the maximum effective half-aperture of the image side of the third lens, and SD11 is the maximum effective half-aperture of the object side of the first lens .
  • SD32/SD11 can be 0.89, 0.94, 0.99, 1.04, 1.09, 1.13, 1.17, 1.21, 1.25 or 1.29.
  • the structural design of the optical imaging system can be made more compact, so as to reduce its space occupation volume and achieve miniaturization; at the same time, more light can be incident into the optical imaging system to improve the picture quality. Relative brightness.
  • SD32/SD11 When SD32/SD11 is less than or equal to 0.85, it is difficult to shorten the distance between the lenses in order to ensure the amount of light, and it is easy to increase the space occupied by the optical imaging system, which is not conducive to the miniaturization of the lens; and when SD32/SD11 is greater than or equal to 1.3 , Will make the effective aperture of the first lens smaller and cannot guarantee the amount of light entering the optical image system, resulting in lower relative brightness of the picture.
  • the optical imaging system satisfies the following relationship: FFL>0.7mm; where FFL is the point where the fifth lens image side is projected on the optical axis from the point farthest from the center of the lens surface to the imaging surface of the optical imaging system distance.
  • the FFL can be 0.72mm, 0.74mm, 0.76mm, 0.78mm, 0.80mm, 0.82mm, 0.84mm, or 0.86mm.
  • the optical imaging system can have enough focusing space during the installation of the lens module, thereby improving the assembly yield of the lens module, and at the same time, it can effectively increase the focal depth of the optical imaging system to obtain More depth information of the subject.
  • the focal depth of the optical imaging system is small, which makes it difficult to improve the resolution of the image, and at the same time, it also affects the assembly yield of the lens module.
  • the optical imaging system satisfies the following relationship: R9/R10 ⁇ 1.0; where R9 is the radius of curvature of the fifth lens object side at the optical axis, and R10 is the fifth lens image side at the optical axis.
  • R9/R10 can be 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, or 0.99.
  • the workability of the fifth lens can be enhanced, thereby facilitating correction
  • the coma of the optical imaging system can also prevent other aberrations of the optical imaging system from being too large.
  • R9/R10 is greater than or equal to 1.0, the processing difficulty of the fifth lens will increase, which is not conducive to the correction of coma aberration of the optical imaging system, and it is also not conducive to suppressing other aberrations of the optical imaging system.
  • the optical imaging system satisfies the following relationship: 1.0 ⁇
  • can be 1.25, 1.5, 1.75, 2.0, 2.25, 2.5, 2.75, 3.0, 3.5, 4.0, 4.5, 4.75, 5.0, or 5.5. Under the condition of satisfying the above relationship, it is beneficial to correct the astigmatic aberration of the optical imaging system, thereby improving the imaging quality of the optical imaging system.
  • is less than or equal to 1.0 or greater than or equal to 6.0, the processing difficulty of the third lens will be increased, which is not conducive to correcting the astigmatic aberration of the optical imaging system.
  • the material of each lens in the optical imaging system may be glass or plastic.
  • the plastic lens can reduce the weight and production cost of the optical imaging system, while the glass lens can make the optical imaging system. It has good temperature tolerance and excellent optical performance. It should be noted that the material of each lens in the optical imaging system can also be any combination of glass and plastic, and not necessarily all glass or plastic.
  • a diaphragm is further provided in the optical imaging system to effectively suppress an excessive increase in the incidence angle of the chief ray of the off-axis field of view, so that the optical imaging system can better match the photosensitive elements of traditional specifications.
  • the diaphragm includes an aperture diaphragm and a field diaphragm, and can be arranged on the object side of the first lens or between the first lens and the fifth lens.
  • the diaphragm is an aperture diaphragm.
  • the aperture stop can be located on the surface of the first lens and the second lens (for example, the object side and the image side), and form a functional relationship with the lens, for example, by coating a light-blocking coating on the surface of the lens to form an aperture on the surface Aperture; or the surface of the lens is fixed and clamped by a clamp, and the clamp structure on the surface can limit the width of the imaging beam of the object point on the axis, thereby forming an aperture diaphragm on the surface.
  • the optical imaging system further includes a protective glass for protecting the photosensitive element, wherein the photosensitive element is located on the imaging surface of the optical imaging system.
  • the imaging surface may be the photosensitive surface of the photosensitive element.
  • the optical imaging system may employ multiple lenses, such as the five lenses described above.
  • multiple lenses such as the five lenses described above.
  • FNO can be 1.1
  • the optical imaging system is not limited to including five lenses, and if necessary, the optical imaging system may also include other numbers of lenses.
  • FIG. 1 shows a schematic structural diagram of the optical imaging system of Embodiment 1.
  • the optical imaging system includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an imaging surface S13 in order from the object side to the image side along the optical axis. .
  • the first lens L1 has a positive refractive power.
  • the object side S1 and the image side S2 are both aspherical.
  • the object side S1 is convex at the optical axis and concave at the circumference.
  • the image side S2 is concave at the optical axis.
  • the circumference is convex.
  • the second lens L2 has a positive refractive power.
  • the object side surface S3 and the image side surface S4 are both aspherical.
  • the object side surface S3 is convex at the optical axis and convex at the circumference, and the image side S4 is concave at the optical axis.
  • the circumference is concave.
  • the third lens L3 has a positive refractive power.
  • the object side surface S5 and the image side surface S6 are both aspherical.
  • the object side surface S5 is convex at the optical axis and concave at the circumference.
  • the image side S6 is concave at the optical axis.
  • the circumference is convex.
  • the fourth lens L4 has a negative refractive power.
  • the object side surface S7 and the image side surface S8 are both aspherical.
  • the object side surface S7 is concave at the optical axis and concave at the circumference.
  • the image side S8 is convex at the optical axis.
  • the circumference is concave.
  • the fifth lens L5 has a positive refractive power.
  • the object side surface S9 and the image side surface S10 are both aspherical.
  • the object side surface S9 is convex at the optical axis and concave at the circumference, and the image side S10 is concave at the optical axis.
  • the circumference is convex.
  • lens surfaces S1 to S10 can help solve the problem of distortion of the field of view. It can also make the lens smaller, thinner and flat to achieve excellent optical imaging effects, thereby making the optical imaging system compact ⁇ Characterization.
  • the materials of the first lens L1 to the fifth lens L5 are all plastic, which can reduce the weight of the optical imaging system and reduce the production cost.
  • a stop STO is also provided on the object side of the first lens L1 to further improve the imaging quality of the optical imaging system.
  • the optical imaging system further includes an infrared band pass filter L6 having an object side surface S11 and an image side surface S12.
  • the infrared band pass filter L6 is provided between the fifth lens L5 and the imaging surface S13.
  • the light from the object OBJ sequentially passes through the respective surfaces S1 to S12 and is finally imaged on the imaging surface S13.
  • the infrared band-pass filter L6 is used to filter out the light in the wavelength band other than 840 nm to 950 nm, so as to meet the application requirements of the TOF lens.
  • the material of the infrared band pass filter L6 is glass.
  • Table 1 shows the surface type, radius of curvature, thickness, material, refractive index, Abbe number (ie, dispersion coefficient) and effective focal length of each lens of the optical imaging system of Example 1, where the radius of curvature and thickness
  • the unit of effective focal length of each lens is millimeter (mm).
  • the TTL is the distance from the object side surface S1 of the first lens L1 to the imaging surface S13 on the optical axis.
  • the surface of each lens closest to the object is called the object side, and the surface of each lens closest to the imaging surface is called the image side.
  • the first value in the "thickness" parameter column of the first lens L1 is the thickness of the lens on the optical axis
  • the second value is the direction from the image side to the image side of the lens.
  • the reference wavelength in Table 1 is 940nm.
  • the aspheric surface type in each lens is defined by the following formula:
  • x is the distance vector height of the aspheric surface from the apex of the aspheric surface when the height is h along the optical axis direction;
  • k is the conic coefficient;
  • Ai is the i-th order coefficient of the aspheric surface.
  • Table 2 below shows the higher order term coefficients A4, A6, A8, A10, A12, A14, A16, A18, and A20 that can be used for the lens aspheric surfaces S1-S10 in Example 1.
  • TT/f 1.366, where TT is the distance from the object side S1 of the first lens L1 to the image side S10 of the fifth lens L5 on the optical axis, and f is the effective focal length of the optical imaging system;
  • CT1+CT2+CT3 1.32mm, where CT1 is the thickness of the first lens L1 on the optical axis, CT2 is the thickness of the second lens L2 on the optical axis, and CT3 is the thickness of the third lens L3 on the optical axis;
  • T12+T23+T34+T45 0.78mm, where T12 is the distance on the optical axis from the image side surface S2 of the first lens L1 to the object side surface S3 of the second lens L2, and T23 is the distance from the image side surface S4 to the third lens of the second lens L2 L3 is the distance on the optical axis of the object side S5, T34 is the distance on the optical axis from the third lens L3 image side S6 to the fourth lens L4 object side S7, and T45 is the fourth lens L4 image side S8 to the fifth lens L5 object The distance of side S9 on the optical axis;
  • f3/f5 1.291, where f3 is the effective focal length of the third lens L3, and f5 is the effective focal length of the fifth lens L5;
  • FNO 1.17, where FNO is the aperture number of the optical imaging system
  • SD32/SD11 1.06, where SD32 is the maximum effective half diameter of the third lens L3 on the image side S6, and SD11 is the maximum effective half diameter of the first lens L1 on the object side S1;
  • FFL 0.76mm, where FFL is the distance from the point farthest from the center of the lens surface on the optical axis of the fifth lens L5 on the image side surface S10 of the fifth lens L5 to the imaging surface S13 of the optical imaging system;
  • R9/R10 0.881, where R9 is the radius of curvature of the fifth lens L5 on the optical axis of the object side surface S9, and R10 is the curvature radius of the fifth lens L5 on the optical axis of the image side surface S10;
  • Fig. 2 shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system of Embodiment 1.
  • the longitudinal spherical aberration graph shows the deviation of the focal point of infrared rays with wavelengths of 930nm, 940nm, and 950nm after passing through the optical imaging system;
  • the astigmatism graph shows the meridional image plane curvature and arc of the optical imaging system of Example 1.
  • the sagittal image plane is curved;
  • the distortion curve diagram shows the distortion rate of the optical imaging system of Example 1 under different image heights. According to FIG. 2, it can be seen that the optical imaging system given in Example 1 can achieve good imaging quality.
  • FIG. 3 shows a schematic structural diagram of an optical imaging system according to Embodiment 2 of the present application.
  • the optical imaging system includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an imaging surface S13 in order from the object side to the image side along the optical axis. .
  • the first lens L1 has a positive refractive power.
  • the object side S1 and the image side S2 are both aspherical.
  • the object side S1 is convex at the optical axis and concave at the circumference.
  • the image side S2 is concave at the optical axis.
  • the circumference is convex.
  • the second lens L2 has a negative refractive power.
  • the object side surface S3 and the image side surface S4 are both aspherical.
  • the object side surface S3 is concave at the optical axis and concave at the circumference.
  • the image side S4 is convex at the optical axis.
  • the circumference is convex.
  • the third lens L3 has a positive refractive power.
  • the object side surface S5 and the image side surface S6 are both aspherical.
  • the object side surface S5 is convex at the optical axis and concave at the circumference.
  • the image side S6 is concave at the optical axis.
  • the circumference is convex.
  • the fourth lens L4 has a negative refractive power.
  • the object side surface S7 and the image side surface S8 are both aspherical.
  • the object side surface S7 is concave at the optical axis and concave at the circumference.
  • the image side S8 is convex at the optical axis.
  • the circumference is concave.
  • the fifth lens L5 has a positive refractive power.
  • the object side surface S9 and the image side surface S10 are both aspherical.
  • the object side surface S9 is convex at the optical axis and concave at the circumference, and the image side S10 is concave at the optical axis.
  • the circumference is convex.
  • lens surfaces S1 to S10 can help solve the problem of distortion of the field of view. It can also make the lens smaller, thinner and flat to achieve excellent optical imaging effects, thereby making the optical imaging system compact ⁇ Characterization.
  • the materials of the first lens L1 to the fifth lens L5 are all plastic, which can reduce the weight of the optical imaging system and reduce the production cost.
  • a stop STO is also provided on the object side of the first lens L1 to further improve the imaging quality of the optical imaging system.
  • the optical imaging system also includes an infrared band-pass filter L6 having an object side surface S11 and an image side surface S12, which is used to filter out light in the wavelength band other than 840 nm to 950 nm to meet the application requirements of TOF lenses.
  • the material of the infrared band pass filter L6 is glass.
  • Table 3 shows the surface type, radius of curvature, thickness, material, refractive index, Abbe number (ie, dispersion coefficient) and effective focal length of each lens of the optical imaging system of Example 2, where the radius of curvature and thickness The unit of effective focal length of each lens is millimeter (mm).
  • the reference wavelength in Table 3 is 940nm.
  • Table 4 shows the coefficients of the higher order terms that can be used for the lens aspheric surface S1-S10 in Example 2, where the aspheric surface type can be defined by the formula (1) given in Example 1;
  • Table 5 shows Example 2 The relevant parameter values of the optical imaging system.
  • FIG. 4 shows the longitudinal spherical aberration curve, astigmatism curve and distortion curve of the optical imaging system of Embodiment 2 respectively.
  • the longitudinal spherical aberration graph shows the deviation of the focal point of infrared rays with wavelengths of 930nm, 940nm, and 950nm after passing through the optical imaging system;
  • the astigmatism graph shows the meridional field curvature and arc of the optical imaging system of Example 2.
  • the sagittal image plane is curved;
  • the distortion curve diagram shows the distortion rate of the optical imaging system of Example 2 under different image heights. According to FIG. 4, it can be seen that the optical imaging system given in Embodiment 2 can achieve good imaging quality.
  • FIG. 5 shows a schematic structural diagram of an optical imaging system according to Embodiment 3 of the present application.
  • the optical imaging system includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an imaging surface S13 in order from the object side to the image side along the optical axis. .
  • the first lens L1 has a positive refractive power.
  • the object side S1 and the image side S2 are both aspherical.
  • the object side S1 is convex at the optical axis and concave at the circumference.
  • the image side S2 is concave at the optical axis.
  • the circumference is convex.
  • the second lens L2 has a negative refractive power.
  • the object side surface S3 and the image side surface S4 are both aspherical.
  • the object side surface S3 is concave at the optical axis and concave at the circumference.
  • the image side S4 is convex at the optical axis.
  • the circumference is convex.
  • the third lens L3 has a positive refractive power.
  • the object side surface S5 and the image side surface S6 are both aspherical.
  • the object side surface S5 is convex at the optical axis and concave at the circumference.
  • the image side S6 is concave at the optical axis.
  • the circumference is convex.
  • the fourth lens L4 has a negative refractive power.
  • the object side surface S7 and the image side surface S8 are both aspherical.
  • the object side surface S7 is concave at the optical axis and concave at the circumference.
  • the image side S8 is convex at the optical axis.
  • the circumference is concave.
  • the fifth lens L5 has a positive refractive power.
  • the object side surface S9 and the image side surface S10 are both aspherical.
  • the object side surface S9 is convex at the optical axis and concave at the circumference, and the image side S10 is concave at the optical axis.
  • the circumference is convex.
  • lens surfaces S1 to S10 can help solve the problem of distortion of the field of view. It can also make the lens smaller, thinner and flat to achieve excellent optical imaging effects, thereby making the optical imaging system compact ⁇ Characterization.
  • the materials of the first lens L1 to the fifth lens L5 are all plastic, which can reduce the weight of the optical imaging system and reduce the production cost.
  • a stop STO is also provided on the object side of the first lens L1 to further improve the imaging quality of the optical imaging system.
  • the optical imaging system also includes an infrared band-pass filter L6 having an object side surface S11 and an image side surface S12, which is used to filter out light in the wavelength band other than 840 nm to 950 nm to meet the application requirements of TOF lenses.
  • the material of the infrared band pass filter L6 is glass.
  • Table 6 shows the surface type, radius of curvature, thickness, material, refractive index, Abbe number (ie dispersion coefficient), and effective focal length of each lens of the optical imaging system of Example 3.
  • the radius of curvature, thickness The unit of effective focal length of each lens is millimeter (mm).
  • the reference wavelength in Table 6 is 940nm.
  • Table 7 shows the coefficients of the higher order term that can be used for the lens aspheric surface S1-S10 in Example 3, where the aspheric surface type can be defined by the formula (1) given in Example 1;
  • Table 8 shows Example 3 The relevant parameter values of the optical imaging system.
  • Fig. 6 shows the longitudinal spherical aberration curve, the astigmatism curve and the distortion curve of the optical imaging system of Embodiment 3, respectively.
  • the longitudinal spherical aberration graph shows the deviation of the focal point of infrared rays with wavelengths of 930nm, 940nm, and 950nm after passing through the optical imaging system;
  • the astigmatism graph shows the meridional image plane curvature and arc of the optical imaging system of Example 3.
  • the sagittal image plane is curved;
  • the distortion curve diagram shows the distortion rate of the optical imaging system of Example 3 under different image heights. According to FIG. 6, it can be seen that the optical imaging system given in Embodiment 3 can achieve good imaging quality.
  • FIG. 7 shows a schematic structural diagram of an optical imaging system according to Embodiment 4 of the present application.
  • the optical imaging system includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an imaging surface S13 in order from the object side to the image side along the optical axis. .
  • the first lens L1 has a negative refractive power.
  • the object side S1 and the image side S2 are both aspherical.
  • the object side S1 is convex at the optical axis and convex at the circumference.
  • the image side S2 is concave at the optical axis.
  • the circumference is convex.
  • the second lens L2 has a positive refractive power.
  • the object side surface S3 and the image side surface S4 are both aspherical.
  • the object side surface S3 is convex at the optical axis and concave at the circumference, and the image side S4 is concave at the optical axis.
  • the circumference is convex.
  • the third lens L3 has positive refractive power.
  • the object side surface S5 and the image side surface S6 are both aspherical.
  • the object side surface S5 is concave at the optical axis and concave at the circumference.
  • the image side S6 is convex at the optical axis.
  • the circumference is convex.
  • the fourth lens L4 has a negative refractive power.
  • the object side surface S7 and the image side surface S8 are both aspherical.
  • the object side surface S7 is concave at the optical axis and concave at the circumference.
  • the image side S8 is convex at the optical axis.
  • the circumference is concave.
  • the fifth lens L5 has a positive refractive power.
  • the object side surface S9 and the image side surface S10 are both aspherical.
  • the object side surface S9 is convex at the optical axis and concave at the circumference, and the image side S10 is concave at the optical axis.
  • the circumference is convex.
  • lens surfaces S1 to S10 can help solve the problem of distortion of the field of view. It can also make the lens smaller, thinner and flat to achieve excellent optical imaging effects, thereby making the optical imaging system compact ⁇ Characterization.
  • the materials of the first lens L1 to the fifth lens L5 are all plastic, which can reduce the weight of the optical imaging system and reduce the production cost.
  • a stop STO is also provided on the object side of the first lens L1 to further improve the imaging quality of the optical imaging system.
  • the optical imaging system also includes an infrared band-pass filter L6 having an object side surface S11 and an image side surface S12, which is used to filter out light in the wavelength band other than 840 nm to 950 nm to meet the application requirements of TOF lenses.
  • the material of the infrared band pass filter L6 is glass.
  • Table 9 shows the surface type, radius of curvature, thickness, material, refractive index, Abbe number (ie dispersion coefficient) and effective focal length of each lens of the optical imaging system of Example 4, where the radius of curvature and thickness The unit of effective focal length of each lens is millimeter (mm).
  • the reference wavelength in Table 9 is 940 nm.
  • Table 10 shows the coefficients of the higher order terms that can be used for the lens aspheric surface S1-S10 in Example 4, where the aspheric surface type can be defined by the formula (1) given in Example 1;
  • Table 11 shows Example 4 The relevant parameter values of the optical imaging system.
  • FIG. 8 shows the longitudinal spherical aberration curve, astigmatism curve, and distortion curve of the optical imaging system of Embodiment 4, respectively.
  • the longitudinal spherical aberration graph shows the deviation of the focal point of infrared rays with wavelengths of 930nm, 940nm and 950nm after passing through the optical imaging system;
  • the astigmatism graph shows the meridional image plane curvature and arc of the optical imaging system of Example 4.
  • the sagittal image plane is curved;
  • the distortion curve diagram shows the distortion rate of the optical imaging system of Example 4 under different image heights. According to FIG. 8, it can be seen that the optical imaging system given in Embodiment 4 can achieve good imaging quality.
  • FIG. 9 shows a schematic structural diagram of an optical imaging system according to Embodiment 5 of the present application.
  • the optical imaging system includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an imaging surface S13 in order from the object side to the image side along the optical axis. .
  • the first lens L1 has a negative refractive power.
  • the object side S1 and the image side S2 are both aspherical.
  • the object side S1 is convex at the optical axis and concave at the circumference.
  • the image side S2 is concave at the optical axis.
  • the circumference is convex.
  • the second lens L2 has a positive refractive power.
  • the object side surface S3 and the image side surface S4 are both aspherical.
  • the object side surface S3 is convex at the optical axis and concave at the circumference.
  • the image side S4 is convex at the optical axis.
  • the circumference is convex.
  • the third lens L3 has a positive refractive power.
  • the object side surface S5 and the image side surface S6 are both aspherical.
  • the object side surface S5 is convex at the optical axis and convex at the circumference, and the image side S6 is concave at the optical axis.
  • the circumference is convex.
  • the fourth lens L4 has a negative refractive power.
  • the object side surface S7 and the image side surface S8 are both aspherical.
  • the object side surface S7 is concave at the optical axis and concave at the circumference.
  • the image side S8 is concave at the optical axis.
  • the circumference is concave.
  • the fifth lens L5 has a positive refractive power, and the object side surface S9 and the image side surface S10 are both aspherical.
  • the object side surface S9 is convex at the optical axis and concave at the circumference, and the image side S10 is concave at the optical axis.
  • the circumference is convex.
  • lens surfaces S1 to S10 can help solve the problem of distortion of the field of view. It can also make the lens smaller, thinner and flat to achieve excellent optical imaging effects, thereby making the optical imaging system compact ⁇ Characterization.
  • the materials of the first lens L1 to the fifth lens L5 are all plastic, which can reduce the weight of the optical imaging system and reduce the production cost.
  • a stop STO is also arranged between the first lens L1 and the second lens L2 to further improve the imaging quality of the optical imaging system.
  • the optical imaging system also includes an infrared band-pass filter L6 having an object side surface S11 and an image side surface S12, which is used to filter out light in the wavelength band other than 840 nm to 950 nm to meet the application requirements of TOF lenses.
  • the material of the infrared band pass filter L6 is glass.
  • Table 12 shows the surface type, radius of curvature, thickness, material, refractive index, Abbe number (ie dispersion coefficient) and effective focal length of each lens of the optical imaging system of Example 5, where the radius of curvature and thickness The unit of effective focal length of each lens is millimeter (mm).
  • the reference wavelength in Table 12 is 940 nm.
  • Table 13 shows the coefficients of the higher order terms that can be used for the lens aspheric surface S1-S10 in Example 5, where the aspheric surface type can be defined by the formula (1) given in Example 1;
  • Table 14 shows Example 5 The relevant parameter values of the optical imaging system.
  • FIG. 10 shows the longitudinal spherical aberration curve, the astigmatism curve and the distortion curve of the optical imaging system of Embodiment 5, respectively.
  • the longitudinal spherical aberration graph shows the deviation of the focal point of infrared rays with wavelengths of 930nm, 940nm, and 950nm after passing through the optical imaging system;
  • the astigmatism graph shows the meridional image plane curvature and arc of the optical imaging system of Example 5.
  • the sagittal image plane is curved;
  • the distortion curve diagram shows the distortion rate of the optical imaging system of Example 5 under different image heights. According to FIG. 10, it can be seen that the optical imaging system given in Embodiment 5 can achieve good imaging quality.
  • FIG. 11 shows a schematic structural diagram of an optical imaging system according to Embodiment 6 of the present application.
  • the optical imaging system includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, and an imaging surface S13 in order from the object side to the image side along the optical axis. .
  • the first lens L1 has a positive refractive power.
  • the object side S1 and the image side S2 are both aspherical.
  • the object side S1 is convex at the optical axis and concave at the circumference.
  • the image side S2 is concave at the optical axis.
  • the circumference is convex.
  • the second lens L2 has a positive refractive power.
  • the object side surface S3 and the image side surface S4 are both aspherical.
  • the object side surface S3 is concave at the optical axis and concave at the circumference.
  • the image side S4 is convex at the optical axis.
  • the circumference is convex.
  • the third lens L3 has a positive refractive power.
  • the object side surface S5 and the image side surface S6 are both aspherical.
  • the object side surface S5 is convex at the optical axis and concave at the circumference.
  • the image side S6 is concave at the optical axis.
  • the circumference is convex.
  • the fourth lens L4 has a negative refractive power.
  • the object side surface S7 and the image side surface S8 are both aspherical.
  • the object side surface S7 is concave at the optical axis and concave at the circumference.
  • the image side S8 is convex at the optical axis.
  • the circumference is concave.
  • the fifth lens L5 has a positive refractive power.
  • the object side surface S9 and the image side surface S10 are both aspherical.
  • the object side surface S9 is convex at the optical axis and concave at the circumference, and the image side S10 is concave at the optical axis.
  • the circumference is convex.
  • lens surfaces S1 to S10 can help solve the problem of distortion of the field of view. It can also make the lens smaller, thinner and flat to achieve excellent optical imaging effects, thereby making the optical imaging system compact ⁇ Characterization.
  • the materials of the first lens L1 to the fifth lens L5 are all plastic, which can reduce the weight of the optical imaging system and reduce the production cost.
  • a stop STO is also arranged between the first lens L1 and the second lens L2 to further improve the imaging quality of the optical imaging system.
  • the optical imaging system also includes an infrared band-pass filter L6 having an object side surface S11 and an image side surface S12, which is used to filter out light in the wavelength band other than 840 nm to 950 nm to meet the application requirements of TOF lenses.
  • the material of the infrared band pass filter L6 is glass.
  • Table 15 shows the surface type, radius of curvature, thickness, material, refractive index, Abbe number (ie dispersion coefficient) and effective focal length of each lens of the optical imaging system of Example 6, where the radius of curvature and thickness The unit of effective focal length of each lens is millimeter (mm).
  • the reference wavelength in Table 15 is 940 nm.
  • Table 16 shows the coefficients of the higher order term that can be used for the lens aspheric surface S1-S10 in Example 6, where the aspheric surface type can be defined by the formula (1) given in Example 1;
  • Table 17 shows Example 6 The relevant parameter values of the optical imaging system.
  • FIG. 12 shows the longitudinal spherical aberration curve, the astigmatism curve, and the distortion curve of the optical imaging system of Embodiment 6 respectively.
  • the longitudinal spherical aberration graph shows the deviation of the focal point of infrared rays with wavelengths of 930nm, 940nm, and 950nm after passing through the optical imaging system;
  • the astigmatism graph shows the meridional image plane curvature and arc of the optical imaging system of Example 6.
  • the sagittal image plane is curved;
  • the distortion curve diagram shows the distortion rate of the optical imaging system of Example 6 under different image heights. According to FIG. 12, it can be seen that the optical imaging system given in Embodiment 6 can achieve good imaging quality.
  • the present application also provides an imaging module, including the optical imaging system as described above; and a photosensitive element, which is arranged on the image side of the optical imaging system to receive the light projected by the optical imaging system.
  • the photosensitive element may adopt a complementary metal oxide semiconductor (CMOS, Complementary Metal Oxide Semiconductor) image sensor or a charge-coupled device (CCD, Charge-coupled Device) image sensor.
  • CMOS complementary metal oxide semiconductor
  • CCD Charge-coupled Device
  • the above-mentioned imaging module using the aforementioned optical imaging system, can image the infrared light emitted or reflected by the subject, and capture images with bright pictures, high resolution and small aberrations.
  • the imaging device also has a miniaturized Features, easy to adapt to devices with limited size such as thin and light electronic equipment.
  • the present application also provides an electronic device, including a housing and the image capturing module as described above, and the image capturing module is installed on the housing for capturing images.
  • the image capturing device is arranged in the casing and exposed from the casing to capture images.
  • the casing can provide protection against dust, water, and drop of the image capturing device.
  • the casing is provided with holes corresponding to the image capturing device. Make light penetrate into or out of the shell from the hole.
  • the above-mentioned electronic device has the characteristics of light and thin structure, and a clearer image containing the depth information of the subject can be captured by using the aforementioned imaging device.
  • the "electronic device” used may include, but is not limited to, a device configured to be connected via a wired line and/or receive or send a communication signal via a wireless interface.
  • An electronic device set to communicate through a wireless interface may be referred to as a "wireless communication terminal", a “wireless terminal” or a “mobile terminal”.
  • mobile terminals include, but are not limited to satellite or cellular phones; personal communication system (PCS) terminals that can combine cellular radio phones with data processing, fax, and data communication capabilities; can include radio phones, pagers, and the Internet/ Personal digital assistant (PDA) with intranet access, web browser, notebook, calendar, and/or global positioning system (GPS) receiver; and conventional laptop and/or palmtop Receiver or other electronic device including a radio telephone transceiver.
  • PCS personal communication system
  • PDA Internet/ Personal digital assistant
  • GPS global positioning system

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Abstract

一种用于红外光成像的光学成像系统，其沿着光轴由物侧至像侧依序包括具有屈折力的第一透镜（L1）；具有屈折力的第二透镜（L2）；具有正屈折力的第三透镜（L3），第三透镜（L3）的像侧面于圆周处为凸面；具有负屈折力的第四透镜（L4）；具有正屈折力的第五透镜（L5），第五透镜的像侧面（S10）于光轴处为凹面，第五透镜的物侧面（S9）与像侧面（S10）均为非球面，且其物侧面（S9）和像侧面（S10）中至少一个表面包含至少一个反曲点；光学成像系统满足下列关系式：TT/f＜1.5；其中，TT为第一透镜物侧面（S1）至第五透镜像侧面（S10）在光轴上的距离，f为光学成像系统的有效焦距。这种光学成像系统能拍摄得到分辨率较高的图像，同时还具备大光圈以及小型化的特点。还公开了一种取像装置和电子装置。

Description

光学成像系统、取像装置及电子装置 技术领域
本申请涉及光学成像技术领域，特别是涉及一种适用于红外光成像的光学成像系统、取像装置及电子装置。
背景技术
随着飞行时间(Time of flight，TOF)技术的飞速发展，结合TOF 3D技术的感光元件，TOF镜头的应用领域变得十分广泛，包括移动设备的人脸解锁、汽车自动驾驶、人机界面与游戏、工业机器视觉与测量、安防监控等。
TOF镜头用于接收被摄物体反射的TOF发射端发出的光线，其与普通光学镜头不同的是需要加一个红外带通滤光片来保证只有与发射端光源波长相同的光才能被感光元件获取。TOF镜头不仅能够记录被摄物体的深度信息去形成图像，而且还可以对不同深度的景物和人进行不同的虚化强度，从而大大提升拍摄效果。
然而，传统的TOF镜头大多是四片式结构，较难获得被摄物体精确的深度信息，导致成像分辨率低，用户的拍摄体验不佳。
发明内容
根据本申请的各种实施例，提供一种光学成像系统。
一种光学成像系统，所述光学成像系统用于红外光成像，其沿着光轴由物侧至像侧依序包括具有屈折力的第一透镜；具有屈折力的第二透镜；具有正屈折力的第三透镜，所述第三透镜的像侧面于圆周处为凸面；具有负屈折力的第四透镜；具有正屈折力的第五透镜，所述第五透镜的像侧面于光轴处为凹面，所述第五透镜的物侧面与像侧面均为非球面，且其物侧面和像侧面中至少一个表面包含至少一个反曲点；所述光学成像系统满足下列关系式：
TT/f＜1.5；
其中，TT为所述第一透镜物侧面至所述第五透镜像侧面在光轴上的距离，f为所述光学成像系统的有效焦距。
一种取像装置，包括上述实施例所述的光学成像系统；以及感光元件，所述感光元件设于所述光学成像系统的像侧。
一种电子装置，包括壳体以及上述实施例所述的取像装置，所述取像装置安装在所述壳体上。
本申请的一个或多个实施例的细节在下面的附图和描述中提出。本申请的其他特征、目的和优点将从说明书、附图以及权利要求书变得明显。
附图说明
为了更好地描述和说明这里公开的那些发明的实施例或示例，可以参考一幅或多幅附图。用于描述附图的附加细节或示例不应当被认为是对所公开的发明、目前描述的实施例或示例以及目前理解的这些发明的最佳模式中的任何一者的范围的限制。
图1示出了本申请实施例1的光学成像系统的结构示意图；
图2分别示出了实施例1的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图；
图3示出了本申请实施例2的光学成像系统的结构示意图；
图4分别示出了实施例2的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图；
图5示出了本申请实施例3的光学成像系统的结构示意图；
图6分别示出了实施例3的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图；
图7示出了本申请实施例4的光学成像系统的结构示意图；
图8分别示出了实施例4的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图；
图9示出了本申请实施例5的光学成像系统的结构示意图；
图10分别示出了实施例5的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图；
图11示出了本申请实施例6的光学成像系统的结构示意图；
图12分别示出了实施例6的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图。
具体实施方式
为了使本申请的目的、技术方案及优点更加清楚明白，以下结合附图及实施例，对本申请进行进一步详细说明。应当理解，此处描述的具体实施例仅仅用以解释本申请，并不用于限定本申请。
需要说明的是，当元件被称为“设置于”另一个元件，它可以直接在另一个元件上或者也可以存在居中的元件。当一个元件被认为是“连接” 另一个元件，它可以是直接连接到另一个元件或者可能同时存在居中元件。本文所使用的术语“垂直的”、“水平的”、“左”、“右”以及类似的表述只是为了说明的目的，并不表示是唯一的实施方式。
应注意，在本说明书中，第一、第二、第三等的表述仅用于将一个特征与另一个特征区分开来，而不表示对特征的任何限制。因此，在不背离本申请的教导的情况下，下文中讨论的第一透镜也可被称作第二透镜或第三透镜。
为了便于说明，附图中所示的球面或非球面的形状通过示例的方式示出。即，球面或非球面的形状不限于附图中示出的球面或非球面的形状。附图仅为示例而并非严格按比例绘制。
除非另有定义，本文所使用的所有的技术和科学术语与属于本申请的技术领域的技术人员通常理解的含义相同。本文中在本申请的说明书中所使用的术语只是为了描述具体的实施例的目的，不是旨在于限制本申请。本文所使用的术语“及/或”包括一个或多个相关的所列项目的任意的和所有的组合。
传统的飞行时间(Time of flight，TOF)镜头为保证小型化，通常采用四片式结构。然而，四片式的TOF镜头较难获得被摄物体更精确的深度信息，成像分辨率也不高，用户拍摄体验不佳。
针对以上方案所存在的缺陷，均是发明人在经过实践并仔细研究后得到的结果，因此，上述问题的发现过程以及下文中本申请实施例针对上述问题所提出的解决方案，都应是发明人在本申请过程中对本申请做出的贡献。
以下将对本申请的特征、原理和其他方面进行详细描述。
请一并参阅图1、图3、图5、图7、图9和图11，本申请实施例提供一种五片式的TOF光学成像系统。该光学成像系统能够对红外光线进行成像，并在保证小型化的同时，成像分辨率也较高，具体包括沿着光轴从物侧至像侧依序排列的第一透镜、第二透镜、第三透镜、第四透镜以及第五透镜，光学成像系统的成像面位于第五透镜的像侧。
第一透镜和第二透镜具有屈折力，以使被摄物体反射的TOF发射端发出的光线能被光学成像系统获取。
第三透镜具有正屈折力，且第三透镜像侧面于光轴处为凸面，有利于修正光学成像系统的像散像差，进而提升光学成像系统的成像品质。
第四透镜具有负屈折力，有利于修正光学成像系统的色差，进而提升光学成像系统的成像品质。
第五透镜具有正屈折力，第五透镜的像侧面于光轴处为凹面，有利于结合第三透镜的正屈折力以平衡第四透镜产生的负球差，并修正光学成像系统的彗差；第五透镜的物侧面和像侧面均为非球面，有利于进一步修正 光学成像系统的像差；第五透镜的物侧面与像侧面中至少一个表面包含至少一个反曲点，可以有效地压制离轴视场的光线入射至感光元件上的角度，使其更精准地匹配感光元件，从而提高感光元件的光能接收效率。
具体的，光学成像系统满足下列关系式：TT/f＜1.5；其中，TT为第一透镜物侧面至第五透镜像侧面在光轴上的距离，f为光学成像系统的有效焦距。TT/f可以是1.0、1.15、1.20、1.25、1.30、1.35、1.40或1.45。在满足上述关系的条件下，可以在缩短光学成像系统总长、保证镜头小型化的同时，使光学成像系统投射的光线更好地汇聚至成像面，从而提升其成像解析能力。而当TT/f大于等于1.5时，会使得第一透镜物侧面至第五透镜像侧面在光轴上的距离过长，不利于系统的小型化；或是光学成像系统的有效焦距过小，使得系统的成像解析能力降低。
当上述光学成像系统用于成像时，被摄物体发出或反射的红外光线从物侧方向进入光学成像系统，并依次穿过第一透镜、第二透镜、第三透镜、第四透镜和第五透镜，最终汇聚到成像面上。
上述光学成像系统，通过合理分配各透镜的屈折力、面型以及各透镜的有效焦距，可以在保证光学成像系统小型化的同时，增强光学成像系统对红外光线的成像解析能力以及暗光拍摄能力。另外，本申请的光学成像系统可以在一个较宽的红外波段范围内均能保持良好的成像质量，从而满足TOF镜头的工作需求。
在示例性实施方式中，第一透镜至第五透镜中各透镜的物侧面和像侧面均可以设置为非球面，从而可以提高透镜设计的灵活性，并有效地校正像差，提升光学成像系统的成像解析度。在另一些实施方式中，光学成像系统的各透镜的物侧面和像侧面也可以均为球面。需要注意的是，上述实施方式仅是对本申请的一些实施方式的举例，在一些实施方式中，光学成像系统中各透镜的表面可以是非球面或球面的任意组合。
在示例性实施方式中，第五透镜和光学成像系统的成像面之间设置有红外带通滤光片。通过设置红外带通滤光片可以对入射至光学成像系统成像面的光线的波段进行选择，例如可仅使被摄物体反射的TOF发射端发出的红外光线通过，从而保证光学成像系统能够满足TOF技术的应用需求。在另一些实施方式中，还可以在第一透镜至第五透镜中的一个透镜的物侧面或像侧面设置滤光膜，以实现相同的波段选择效果，本申请对此不做限制。
在示例性实施方式中，光学成像系统满足下列关系式：
0.7mm＜CT1+CT2+CT3＜1.6mm；其中，CT1为第一透镜在光轴上的厚度，CT2为第二透镜在光轴上的厚度，CT3为第三透镜在光轴上的厚度。 CT1+CT2+CT3可以是0.8mm、0.85mm、0.9mm、0.95mm、1.0mm、1.10mm、1.20mm、1.30mm、1.35mm或1.40mm。在满足上述关系的条件下，可以增强第一透镜对环境的耐受性，并在此基础上配置第二透镜和第三透镜在光轴上的厚度，有利于光学成像系统的小型化设计。而当CT1+CT2+CT3小于等于0.7mm时，会使得透镜过薄而导致镜头强度不高以及制造良率低；而当CT1+CT2+CT3大于等于1.6mm时，会使得透镜过厚而不利于光学成像系统的小型化。
在示例性实施方式中，光学成像系统满足下列关系式：
0.25mm＜T12+T23+T34+T45＜0.95mm；其中，T12为第一透镜像侧面至第二透镜物侧面在光轴上的距离，T23为第二透镜像侧面至第三透镜物侧面在光轴上的距离，T34为第三透镜像侧面至第四透镜物侧面在光轴上的距离，T45为第四透镜像侧面至第五透镜物侧面在光轴上的距离。T12+T23+T34+T45可以是0.3mm、0.35mm、0.4mm、0.45mm、0.5mm、0.55mm、0.6mm、0.65mm、0.7mm、0.75mm、0.8mm或0.9mm。在满足上述关系的条件下，有利于实现光学成像系统的小型化并提升镜头的组装良率。而当T12+T23+T34+T45小于等于0.25mm时，会使得相邻透镜之间的可调整空间间隔过小，容易加大系统敏感度且不利于镜头的组装；而当T12+T23+T34+T45大于等于0.95mm时，则不利于光学成像系统的小型化、超薄化。
在示例性实施方式中，光学成像系统满足下列关系式：0.5＜f3/f5＜3.5；其中，f3为第三透镜的有效焦距，f5为第五透镜的有效焦距。f3/f5可以是0.6、0.7、0.75、0.85、0.95、1.2、1.25、2.0、2.5、3.0、3.1或3.2。在满足上述关系的条件下，有利于为第三透镜和第五透镜分配合适的正屈折力以平衡第四透镜产生的负球差，从而降低光学成像系统的公差敏感度，提高其成像质量。而当f3/f5小于等于0.5时，第三透镜需要提供大部分的正屈折力，导致第三透镜的物侧面会过度弯曲而使其成型不良，进而影响镜头的制造良率；而当f3/f5大于等于3.5时，容易导致第二透镜和第四透镜的屈折力分配不平衡，使得光学成像系统的像差过大，不利于像差修正。
在示例性实施方式中，光学成像系统满足下列关系式：FNO≤1.3；其中，FNO为光学成像系统的光圈数。FNO可以是1.1、1.13、1.16、1.19、1.22、1.25、1.28或1.29。优选的，FNO≤1.1。通过控制光学成像系统的光圈数满足上述关系，能够有效增加光学成像系统的通光量，使其在暗光条件下也能清晰地获取被摄物体的细节信息，从而提升成像品质。而当FNO大于1.3时，光学成像系统的通光量减少，导致画面变暗，同时也较难保留被摄物体的细节信息，使得成像品质降低。
在示例性实施方式中，光学成像系统满足下列关系式：1.4＜nd1＜1.7；1.4＜nd2＜1.7；1.4＜nd4＜1.7；其中，nd1为第一透镜的折射率，nd2为第二透镜的折射率，nd4为第四透镜的折射率。nd1、nd2和nd4均可以是1.5、1.54、1.545、1.546、1.548、1.550、1.6、1.64或1.66。通过合理选择透镜材料，使得第一透镜、第二透镜和第四透镜的折射率满足上述关系，有利于消除光学成像系统的色差，提高光学成像系统的成像品质。
在示例性实施方式中，光学成像系统满足下列关系式：0.85＜SD32/SD11＜1.3；其中，SD32为第三透镜像侧面的最大有效半口径，SD11为第一透镜物侧面的最大有效半口径。SD32/SD11可以是0.89、0.94、0.99、1.04、1.09、1.13、1.17、1.21、1.25或1.29。在满足上述关系的条件下，可使光学成像系统的结构设计更为紧凑，以减小其空间占用体积，实现小型化；同时，还可以使更多的光线入射进光学成像系统，提升画面的相对亮度。而当SD32/SD11小于等于0.85时，为保证进光量而较难缩短透镜间的距离，容易增加光学成像系统的空间占用体积，不利于镜头的小型化设计；而当SD32/SD11大于等于1.3时，会使得第一透镜的有效通光口径较小而无法保证光学像系统的进光量，导致画面的相对亮度较低。
在示例性实施方式中，光学成像系统满足下列关系式：FFL＞0.7mm；其中，FFL为第五透镜像侧面投影于光轴上距离该透镜表面中心最远的点至光学成像系统成像面的距离。FFL可以是0.72mm、0.74mm、0.76mm、0.78mm、0.80mm、0.82mm、0.84mm或0.86mm。在满足上述关系的条件下，可使光学成像系统在镜头模组的安装过程中有足够的对焦空间，进而提升镜头模组的组装良率，同时还可以有效增加光学成像系统的焦深以获取被摄物体更多的深度信息。而当FFL小于等于0.7时，光学成像系统的焦深较小，从而较难提升图像的分辨率，同时也会对镜头模组的组装良率造成影响。
在示例性实施方式中，光学成像系统满足下列关系式：R9/R10＜1.0；其中，R9为第五透镜物侧面于光轴处的曲率半径，R10为第五透镜像侧面于光轴处的曲率半径。R9/R10可以是0.6、0.65、0.7、0.75、0.8、0.85、0.9、0.95或0.99。通过合理配置第五透镜物侧面于光轴处的曲率半径和第五透镜像侧面于光轴处的曲率半径，使二者满足上述关系，可以增强第五透镜的可加工性，从而有利于修正光学成像系统的彗差，同时也可以防止光学成像系统的其他像差过大。而当R9/R10大于等于1.0时，会增加第五透镜的加工难度，从而不利于光学成像系统的彗差修正，也不利于抑制光学成像系统的其他像差。
在示例性实施方式中，光学成像系统满足下列关系式：1.0＜|f3/R6| ＜6.0；其中，f3为第三透镜的有效焦距，R6为第三透镜像侧面于光轴处的曲率半径。|f3/R6|可以是1.25、1.5、1.75、2.0、2.25、2.5、2.75、3.0、3.5、4.0、4.5、4.75、5.0或5.5。在满足上述关系的条件下，有利于修正光学成像系统的像散像差，进而提升光学成像系统的成像品质。而当|f3/R6|小于等于1.0或大于等于6.0时，均会增加第三透镜的加工难度，从而不利于修正光学成像系统的像散像差。
在示例性实施方式中，光学成像系统中各透镜的材质可以均为玻璃或均为塑料，塑料材质的透镜能够减少光学成像系统的重量并降低生产成本，而玻璃材质的透镜可使光学成像系统具备较好的温度耐受特性以及优良的光学性能。需要注意的是，光学成像系统中各透镜的材质也可以玻璃和塑料的任意组合，并不一定要是均为玻璃或均为塑料。
在示例性实施方式中，光学成像系统中还设置有光阑，以有效抑制离轴视场的主光线入射角过度增大，使得光学成像系统更好地与传统规格的感光元件匹配。具体的，光阑包括孔径光阑和视场光阑，且可以设于第一透镜的物侧或是第一透镜与第五透镜之间。优选的，光阑为孔径光阑。孔径光阑可位于第一透镜和第二透镜的表面上(例如物侧面和像侧面)，并与透镜形成作用关系，例如，通过在透镜的表面涂覆阻光涂层以在该表面形成孔径光阑；或通过夹持件固定夹持透镜的表面，位于该表面的夹持件结构能够限制轴上物点成像光束的宽度，从而在该表面上形成孔径光阑。
在示例性实施方式中，光学成像系统还包括用于保护感光元件的保护玻璃，其中感光元件位于光学成像系统的成像面上。进一步的，该成像面可以为感光元件的感光表面。
根据本申请的上述实施方式的光学成像系统可采用多片镜片，例如上文所述的五片。通过合理分配各透镜焦距、屈折力、面型、厚度以及各透镜之间的轴上间距等，可以保证上述光学成像系统的总长较小且具备较高的成像分辨率，同时还具备较大光圈(FNO可以为1.1)，从而更好地满足如车载镜头、手机、平板等轻量化电子设备的对于红外光线成像的应用需求。可以理解的是，虽然在实施方式中以五个透镜为例进行了描述，但是该光学成像系统不限于包括五个透镜，如果需要，该光学成像系统还可包括其它数量的透镜。
下面参照附图进一步描述可适用于上述实施方式的光学成像系统的具体实施例。
实施例1
以下参照图1至图2描述本申请实施例1的光学成像系统。
图1示出了实施例1的光学成像系统的结构示意图。如图1所示，光 学成像系统沿着光轴从物侧至像侧依序包括第一透镜L1、第二透镜L2、第三透镜L3、第四透镜L4、第五透镜L5和成像面S13。
第一透镜L1具有正屈折力，其物侧面S1和像侧面S2均为非球面，其中物侧面S1于光轴处为凸面，于圆周处为凹面，像侧面S2于光轴处为凹面，于圆周处为凸面。
第二透镜L2具有正屈折力，其物侧面S3和像侧面S4均为非球面，其中物侧面S3于光轴处为凸面，于圆周处为凸面，像侧面S4于光轴处为凹面，于圆周处为凹面。
第三透镜L3具有正屈折力，其物侧面S5和像侧面S6均为非球面，其中物侧面S5于光轴处为凸面，于圆周处为凹面，像侧面S6于光轴处为凹面，于圆周处为凸面。
第四透镜L4具有负屈折力，其物侧面S7和像侧面S8均为非球面，其中物侧面S7于光轴处为凹面，于圆周处为凹面，像侧面S8于光轴处为凸面，于圆周处为凹面。
第五透镜L5具有正屈折力，其物侧面S9和像侧面S10均为非球面，其中物侧面S9于光轴处为凸面，于圆周处为凹面，像侧面S10于光轴处为凹面，于圆周处为凸面。
将透镜表面S1至S10均设置为非球面，有利于解决视界歪曲的问题，也能够使透镜在较小、较薄且较平的情况下实现优良的光学成像效果，进而使光学成像系统具备小型化特性。
第一透镜L1至第五透镜L5的材质均为塑料，能够减少光学成像系统的重量并降低生产成本。第一透镜L1的物侧还设置有光阑STO，以进一步提升光学成像系统的成像质量。
光学成像系统还包括具有物侧面S11和像侧面S12的红外带通滤光片L6。红外带通滤光片L6设于第五透镜L5和成像面S13之间。来自物体OBJ的光依序穿过各表面S1至S12并最终成像在成像面S13上。进一步的，红外带通滤光片L6用于滤除840nm～950nm以外的波段的光线，以满足TOF镜头的应用需求。具体的，红外带通滤光片L6的材质为玻璃。
表1示出了实施例1的光学成像系统的各透镜的表面类型、曲率半径、厚度、材质、折射率、阿贝数(即色散系数)和各透镜的有效焦距，其中，曲率半径、厚度、各透镜的有效焦距的单位均为毫米(mm)。其中TTL为第一透镜L1物侧面S1至成像面S13在光轴上的距离。每个透镜中最靠近物体的表面称为物侧面，每个透镜中最靠近成像面的表面称为像侧面。另外，以第一透镜L1为例，第一透镜L1的“厚度”参数列中的第一个数值为该透镜在光轴上的厚度，第二个数值为该透镜的像侧面至像侧方向的后 一透镜的物侧面在光轴上的距离。表1的参考波长为940nm。
表1
Figure PCTCN2020072054-appb-000001
各透镜中的非球面面型由以下公式限定：
Figure PCTCN2020072054-appb-000002
其中，x为非球面沿光轴方向在高度为h的位置时，距非球面顶点的距离矢高；c为非球面的近轴曲率，c＝1/R(即，近轴曲率c为表1中曲率半径R的倒数)；k为圆锥系数；Ai是非球面的第i阶系数。下表2给出了可用于实施例1中透镜非球面S1-S10的高次项系数A4、A6、A8、A10、A12、A14、A16、A18和A20。
表2
Figure PCTCN2020072054-appb-000003
Figure PCTCN2020072054-appb-000004
本实施例光学成像系统的成像面S13上有效像素区域对角线长的一半为2.1mm。结合表1和表2中的数据可知，实施例1中的光学成像系统满足：
TT/f＝1.366，其中，TT为第一透镜L1物侧面S1至第五透镜L5像侧面S10在光轴上的距离，f为光学成像系统的有效焦距；
CT1+CT2+CT3＝1.32mm，其中，CT1为第一透镜L1在光轴上的厚度，CT2为第二透镜L2在光轴上的厚度，CT3为第三透镜L3在光轴上的厚度；
T12+T23+T34+T45＝0.78mm，其中，T12为第一透镜L1像侧面S2至第二透镜L2物侧面S3在光轴上的距离，T23为第二透镜L2像侧面S4至第三透镜L3物侧面S5在光轴上的距离，T34为第三透镜L3像侧面S6至第四透镜L4物侧面S7在光轴上的距离，T45为第四透镜L4像侧面S8至第五透镜L5物侧面S9在光轴上的距离；
f3/f5＝1.291，其中，f3为第三透镜L3的有效焦距，f5为第五透镜L5的有效焦距；
FNO＝1.17，其中，FNO为光学成像系统的光圈数；
nd1＝1.545，nd2＝1.541，nd4＝1.546，其中，nd1为第一透镜L1的折射率，nd2为第二透镜L2的折射率，nd4为第四透镜L4的折射率；
SD32/SD11＝1.06，其中，SD32为第三透镜L3像侧面S6的最大有效半口径，SD11为第一透镜L1物侧面S1的最大有效半口径；
FFL＝0.76mm，其中，FFL为第五透镜L5像侧面S10投影于光轴上距离该透镜表面中心最远的点至光学成像系统成像面S13的距离；
R9/R10＝0.881，其中，R9为第五透镜L5物侧面S9于光轴处的曲率半径，R10为第五透镜L5像侧面S10于光轴处的曲率半径；
|f3/R6|＝1.73，其中，f3为第三透镜L3的有效焦距，R6为第三透镜L3像侧面S6于光轴处的曲率半径。
图2分别示出了实施例1的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图。其中纵向球差曲线图示出了波长为930nm、940nm以及950nm的红外光线经由光学成像系统后的会聚焦点偏离；像散曲线图 示出了实施例1的光学成像系统的子午像面弯曲和弧矢像面弯曲；畸变曲线图示出了实施例1的光学成像系统不同像高情况下的畸变率。根据图2可知，实施例1给出的光学成像系统能够实现良好的成像品质。
实施例2
以下参照图3至图4描述本申请实施例2的光学成像系统。在本实施例中，为简洁起见，将省略部分与实施例1相似的描述。图3示出了本申请实施例2的光学成像系统的结构示意图。
如图3所示，光学成像系统沿着光轴从物侧至像侧依序包括第一透镜L1、第二透镜L2、第三透镜L3、第四透镜L4、第五透镜L5和成像面S13。
第一透镜L1具有正屈折力，其物侧面S1和像侧面S2均为非球面，其中物侧面S1于光轴处为凸面，于圆周处为凹面，像侧面S2于光轴处为凹面，于圆周处为凸面。
第二透镜L2具有负屈折力，其物侧面S3和像侧面S4均为非球面，其中物侧面S3于光轴处为凹面，于圆周处为凹面，像侧面S4于光轴处为凸面，于圆周处为凸面。
第三透镜L3具有正屈折力，其物侧面S5和像侧面S6均为非球面，其中物侧面S5于光轴处为凸面，于圆周处为凹面，像侧面S6于光轴处为凹面，于圆周处为凸面。
第四透镜L4具有负屈折力，其物侧面S7和像侧面S8均为非球面，其中物侧面S7于光轴处为凹面，于圆周处为凹面，像侧面S8于光轴处为凸面，于圆周处为凹面。
第五透镜L5具有正屈折力，其物侧面S9和像侧面S10均为非球面，其中物侧面S9于光轴处为凸面，于圆周处为凹面，像侧面S10于光轴处为凹面，于圆周处为凸面。
将透镜表面S1至S10均设置为非球面，有利于解决视界歪曲的问题，也能够使透镜在较小、较薄且较平的情况下实现优良的光学成像效果，进而使光学成像系统具备小型化特性。
第一透镜L1至第五透镜L5的材质均为塑料，能够减少光学成像系统的重量并降低生产成本。第一透镜L1的物侧还设置有光阑STO，以进一步提升光学成像系统的成像质量。
光学成像系统还包括具有物侧面S11和像侧面S12的红外带通滤光片L6，用于滤除840nm～950nm以外的波段的光线，以满足TOF镜头的应用需求。具体的，红外带通滤光片L6的材质为玻璃。
表3示出了实施例2的光学成像系统的各透镜的表面类型、曲率半径、厚度、材质、折射率、阿贝数(即色散系数)和各透镜的有效焦距，其中， 曲率半径、厚度、各透镜的有效焦距的单位均为毫米(mm)。表3的参考波长为940nm。表4示出了可用于实施例2中透镜非球面S1-S10的高次项系数，其中非球面面型可由实施例1中给出的公式(1)限定；表5示出了实施例2的光学成像系统的相关参数数值。
表3
Figure PCTCN2020072054-appb-000005
表4
Figure PCTCN2020072054-appb-000006
Figure PCTCN2020072054-appb-000007
表5
Figure PCTCN2020072054-appb-000008
图4分别示出了实施例2的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图。其中纵向球差曲线图示出了波长为930nm、940nm以及950nm的红外光线经由光学成像系统后的会聚焦点偏离；像散曲线图示出了实施例2的光学成像系统的子午像面弯曲和弧矢像面弯曲；畸变曲线图示出了实施例2的光学成像系统不同像高情况下的畸变率。根据图4可知，实施例2给出的光学成像系统能够实现良好的成像品质。
实施例3
以下参照图5至图6描述本申请实施例3的光学成像系统。在本实施例中，为简洁起见，将省略部分与实施例1相似的描述。图5示出了本申请实施例3的光学成像系统的结构示意图。
如图5所示，光学成像系统沿着光轴从物侧至像侧依序包括第一透镜L1、第二透镜L2、第三透镜L3、第四透镜L4、第五透镜L5和成像面S13。
第一透镜L1具有正屈折力，其物侧面S1和像侧面S2均为非球面，其中物侧面S1于光轴处为凸面，于圆周处为凹面，像侧面S2于光轴处为凹面，于圆周处为凸面。
第二透镜L2具有负屈折力，其物侧面S3和像侧面S4均为非球面，其中物侧面S3于光轴处为凹面，于圆周处为凹面，像侧面S4于光轴处为凸面，于圆周处为凸面。
第三透镜L3具有正屈折力，其物侧面S5和像侧面S6均为非球面，其中物侧面S5于光轴处为凸面，于圆周处为凹面，像侧面S6于光轴处为凹面，于圆周处为凸面。
第四透镜L4具有负屈折力，其物侧面S7和像侧面S8均为非球面，其 中物侧面S7于光轴处为凹面，于圆周处为凹面，像侧面S8于光轴处为凸面，于圆周处为凹面。
第五透镜L5具有正屈折力，其物侧面S9和像侧面S10均为非球面，其中物侧面S9于光轴处为凸面，于圆周处为凹面，像侧面S10于光轴处为凹面，于圆周处为凸面。
将透镜表面S1至S10均设置为非球面，有利于解决视界歪曲的问题，也能够使透镜在较小、较薄且较平的情况下实现优良的光学成像效果，进而使光学成像系统具备小型化特性。
第一透镜L1至第五透镜L5的材质均为塑料，能够减少光学成像系统的重量并降低生产成本。第一透镜L1的物侧还设置有光阑STO，以进一步提升光学成像系统的成像质量。
光学成像系统还包括具有物侧面S11和像侧面S12的红外带通滤光片L6，用于滤除840nm～950nm以外的波段的光线，以满足TOF镜头的应用需求。具体的，红外带通滤光片L6的材质为玻璃。
表6示出了实施例3的光学成像系统的各透镜的表面类型、曲率半径、厚度、材质、折射率、阿贝数(即色散系数)和各透镜的有效焦距，其中，曲率半径、厚度、各透镜的有效焦距的单位均为毫米(mm)。表6的参考波长为940nm。表7示出了可用于实施例3中透镜非球面S1-S10的高次项系数，其中非球面面型可由实施例1中给出的公式(1)限定；表8示出了实施例3的光学成像系统的相关参数数值。
表6
Figure PCTCN2020072054-appb-000009
表7
Figure PCTCN2020072054-appb-000010
表8
Figure PCTCN2020072054-appb-000011
图6分别示出了实施例3的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图。其中纵向球差曲线图示出了波长为930nm、940nm以及950nm的红外光线经由光学成像系统后的会聚焦点偏离；像散曲线图示出了实施例3的光学成像系统的子午像面弯曲和弧矢像面弯曲；畸变曲线图示出了实施例3的光学成像系统不同像高情况下的畸变率。根据图6可知，实施例3给出的光学成像系统能够实现良好的成像品质。
实施例4
以下参照图7至图8描述本申请实施例4的光学成像系统。在本实施例中，为简洁起见，将省略部分与实施例1相似的描述。图7示出了本申请实施例4的光学成像系统的结构示意图。
如图7所示，光学成像系统沿着光轴从物侧至像侧依序包括第一透镜L1、第二透镜L2、第三透镜L3、第四透镜L4、第五透镜L5和成像面S13。
第一透镜L1具有负屈折力，其物侧面S1和像侧面S2均为非球面，其中物侧面S1于光轴处为凸面，于圆周处为凸面，像侧面S2于光轴处为凹面，于圆周处为凸面。
第二透镜L2具有正屈折力，其物侧面S3和像侧面S4均为非球面，其中物侧面S3于光轴处为凸面，于圆周处为凹面，像侧面S4于光轴处为凹面，于圆周处为凸面。
第三透镜L3具有正屈折力，其物侧面S5和像侧面S6均为非球面，其中物侧面S5于光轴处为凹面，于圆周处为凹面，像侧面S6于光轴处为凸面，于圆周处为凸面。
第四透镜L4具有负屈折力，其物侧面S7和像侧面S8均为非球面，其中物侧面S7于光轴处为凹面，于圆周处为凹面，像侧面S8于光轴处为凸面，于圆周处为凹面。
第五透镜L5具有正屈折力，其物侧面S9和像侧面S10均为非球面，其中物侧面S9于光轴处为凸面，于圆周处为凹面，像侧面S10于光轴处为凹面，于圆周处为凸面。
将透镜表面S1至S10均设置为非球面，有利于解决视界歪曲的问题，也能够使透镜在较小、较薄且较平的情况下实现优良的光学成像效果，进而使光学成像系统具备小型化特性。
第一透镜L1至第五透镜L5的材质均为塑料，能够减少光学成像系统的重量并降低生产成本。第一透镜L1的物侧还设置有光阑STO，以进一步提升光学成像系统的成像质量。
光学成像系统还包括具有物侧面S11和像侧面S12的红外带通滤光片L6，用于滤除840nm～950nm以外的波段的光线，以满足TOF镜头的应用需求。具体的，红外带通滤光片L6的材质为玻璃。
表9示出了实施例4的光学成像系统的各透镜的表面类型、曲率半径、厚度、材质、折射率、阿贝数(即色散系数)和各透镜的有效焦距，其中，曲率半径、厚度、各透镜的有效焦距的单位均为毫米(mm)。表9的参考波长为940nm。表10示出了可用于实施例4中透镜非球面S1-S10的高次项系数，其中非球面面型可由实施例1中给出的公式(1)限定；表11示 出了实施例4的光学成像系统的相关参数数值。
表9
Figure PCTCN2020072054-appb-000012
表10
Figure PCTCN2020072054-appb-000013
Figure PCTCN2020072054-appb-000014
表11
Figure PCTCN2020072054-appb-000015
图8分别示出了实施例4的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图。其中纵向球差曲线图示出了波长为930nm、940nm以及950nm的红外光线经由光学成像系统后的会聚焦点偏离；像散曲线图示出了实施例4的光学成像系统的子午像面弯曲和弧矢像面弯曲；畸变曲线图示出了实施例4的光学成像系统不同像高情况下的畸变率。根据图8可知，实施例4给出的光学成像系统能够实现良好的成像品质。
实施例5
以下参照图9至图10描述本申请实施例5的光学成像系统。在本实施例中，为简洁起见，将省略部分与实施例1相似的描述。图9示出了本申请实施例5的光学成像系统的结构示意图。
如图7所示，光学成像系统沿着光轴从物侧至像侧依序包括第一透镜L1、第二透镜L2、第三透镜L3、第四透镜L4、第五透镜L5和成像面S13。
第一透镜L1具有负屈折力，其物侧面S1和像侧面S2均为非球面，其中物侧面S1于光轴处为凸面，于圆周处为凹面，像侧面S2于光轴处为凹面，于圆周处为凸面。
第二透镜L2具有正屈折力，其物侧面S3和像侧面S4均为非球面，其中物侧面S3于光轴处为凸面，于圆周处为凹面，像侧面S4于光轴处为凸面，于圆周处为凸面。
第三透镜L3具有正屈折力，其物侧面S5和像侧面S6均为非球面，其中物侧面S5于光轴处为凸面，于圆周处为凸面，像侧面S6于光轴处为凹面，于圆周处为凸面。
第四透镜L4具有负屈折力，其物侧面S7和像侧面S8均为非球面，其中物侧面S7于光轴处为凹面，于圆周处为凹面，像侧面S8于光轴处为凹面，于圆周处为凹面。
第五透镜L5具有正屈折力，其物侧面S9和像侧面S10均为非球面， 其中物侧面S9于光轴处为凸面，于圆周处为凹面，像侧面S10于光轴处为凹面，于圆周处为凸面。
将透镜表面S1至S10均设置为非球面，有利于解决视界歪曲的问题，也能够使透镜在较小、较薄且较平的情况下实现优良的光学成像效果，进而使光学成像系统具备小型化特性。
第一透镜L1至第五透镜L5的材质均为塑料，能够减少光学成像系统的重量并降低生产成本。第一透镜L1与第二透镜L2之间还设置有光阑STO，以进一步提升光学成像系统的成像质量。
光学成像系统还包括具有物侧面S11和像侧面S12的红外带通滤光片L6，用于滤除840nm～950nm以外的波段的光线，以满足TOF镜头的应用需求。具体的，红外带通滤光片L6的材质为玻璃。
表12示出了实施例5的光学成像系统的各透镜的表面类型、曲率半径、厚度、材质、折射率、阿贝数(即色散系数)和各透镜的有效焦距，其中，曲率半径、厚度、各透镜的有效焦距的单位均为毫米(mm)。表12的参考波长为940nm。表13示出了可用于实施例5中透镜非球面S1-S10的高次项系数，其中非球面面型可由实施例1中给出的公式(1)限定；表14示出了实施例5的光学成像系统的相关参数数值。
表12
Figure PCTCN2020072054-appb-000016
表13
Figure PCTCN2020072054-appb-000017
Figure PCTCN2020072054-appb-000018
表14
Figure PCTCN2020072054-appb-000019
图10分别示出了实施例5的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图。其中纵向球差曲线图示出了波长为930nm、940nm以及950nm的红外光线经由光学成像系统后的会聚焦点偏离；像散曲线图示出了实施例5的光学成像系统的子午像面弯曲和弧矢像面弯曲；畸变曲线图示出了实施例5的光学成像系统不同像高情况下的畸变率。根据图10可知，实施例5给出的光学成像系统能够实现良好的成像品质。
实施例6
以下参照图11至图12描述本申请实施例6的光学成像系统。在本实施例中，为简洁起见，将省略部分与实施例1相似的描述。图11示出了本申请实施例6的光学成像系统的结构示意图。
如图7所示，光学成像系统沿着光轴从物侧至像侧依序包括第一透镜L1、第二透镜L2、第三透镜L3、第四透镜L4、第五透镜L5和成像面S13。
第一透镜L1具有正屈折力，其物侧面S1和像侧面S2均为非球面，其中物侧面S1于光轴处为凸面，于圆周处为凹面，像侧面S2于光轴处为凹面，于圆周处为凸面。
第二透镜L2具有正屈折力，其物侧面S3和像侧面S4均为非球面，其中物侧面S3于光轴处为凹面，于圆周处为凹面，像侧面S4于光轴处为凸面，于圆周处为凸面。
第三透镜L3具有正屈折力，其物侧面S5和像侧面S6均为非球面，其中物侧面S5于光轴处为凸面，于圆周处为凹面，像侧面S6于光轴处为凹面，于圆周处为凸面。
第四透镜L4具有负屈折力，其物侧面S7和像侧面S8均为非球面，其中物侧面S7于光轴处为凹面，于圆周处为凹面，像侧面S8于光轴处为凸面，于圆周处为凹面。
第五透镜L5具有正屈折力，其物侧面S9和像侧面S10均为非球面，其中物侧面S9于光轴处为凸面，于圆周处为凹面，像侧面S10于光轴处为凹面，于圆周处为凸面。
将透镜表面S1至S10均设置为非球面，有利于解决视界歪曲的问题，也能够使透镜在较小、较薄且较平的情况下实现优良的光学成像效果，进而使光学成像系统具备小型化特性。
第一透镜L1至第五透镜L5的材质均为塑料，能够减少光学成像系统的重量并降低生产成本。第一透镜L1与第二透镜L2之间还设置有光阑STO，以进一步提升光学成像系统的成像质量。
光学成像系统还包括具有物侧面S11和像侧面S12的红外带通滤光片L6，用于滤除840nm～950nm以外的波段的光线，以满足TOF镜头的应用需求。具体的，红外带通滤光片L6的材质为玻璃。
表15示出了实施例6的光学成像系统的各透镜的表面类型、曲率半径、厚度、材质、折射率、阿贝数(即色散系数)和各透镜的有效焦距，其中，曲率半径、厚度、各透镜的有效焦距的单位均为毫米(mm)。表15的参考波长为940nm。表16示出了可用于实施例6中透镜非球面S1-S10的高次项系数，其中非球面面型可由实施例1中给出的公式(1)限定；表17示出了实施例6的光学成像系统的相关参数数值。
表15
Figure PCTCN2020072054-appb-000020
Figure PCTCN2020072054-appb-000021
表16
Figure PCTCN2020072054-appb-000022
表17
Figure PCTCN2020072054-appb-000023
Figure PCTCN2020072054-appb-000024
图12分别示出了实施例6的光学成像系统的纵向球差曲线图、像散曲线图以及畸变曲线图。其中纵向球差曲线图示出了波长为930nm、940nm以及950nm的红外光线经由光学成像系统后的会聚焦点偏离；像散曲线图示出了实施例6的光学成像系统的子午像面弯曲和弧矢像面弯曲；畸变曲线图示出了实施例6的光学成像系统不同像高情况下的畸变率。根据图12可知，实施例6给出的光学成像系统能够实现良好的成像品质。
本申请还提供一种取像模组，包括如前文所述的光学成像系统；以及感光元件，感光元件设于光学成像系统的像侧，以接收由光学成像系统投射的光线。具体的，感光元件可以采用互补金属氧化物半导体(CMOS，Complementary Metal Oxide Semiconductor)图像传感器或者电荷耦合元件(CCD,Charge-coupled Device)图像传感器。
上述取像模组，利用前述光学成像系统能够对被摄物体发出或反射的红外光线成像，并拍摄得到画面明亮、分辨率高且像差小的图像，同时该取像装置还具有小型化的特点，方便适配至如轻薄型电子设备等尺寸受限的装置。
本申请还提供一种电子装置，包括壳体以及如前文所述的取像模组，所述取像模组安装在所述壳体上，用以获取图像。
具体的，取像装置设置在壳体内并从壳体暴露以获取图像，壳体可以给取像装置提供防尘、防水防摔等保护，壳体上开设有与取像装置对应的孔，以使光线从孔中穿入或穿出壳体。
上述电子装置，具有轻薄化的结构特点，利用前述的取像装置可以拍摄得到更清晰的包含被摄物体深度信息的图像。
另一些实施方式中，所使用到的“电子装置”可包括，但不限于被设置成经由有线线路连接和/或经由无线接口接收或发送通信信号的装置。被设置成通过无线接口通信的电子装置可以被称为“无线通信终端”、“无线终端”或“移动终端”。移动终端的示例包括，但不限于卫星或蜂窝电话；可以组合蜂窝无线电电话与数据处理、传真以及数据通信能力的个人通信系统(personal communication system，PCS)终端；可以包括无线电电话、寻呼机、因特网/内联网接入、Web浏览器、记事簿、日历以及/或全球定位系统(global positioning system,GPS)接收器的个人数字助理(personal digital assistant，PDA)；以及常规膝上型和/或掌上 型接收器或包括无线电电话收发器的其它电子装置。
以上所述实施例的各技术特征可以进行任意的组合，为使描述简洁，未对上述实施例中的各个技术特征所有可能的组合都进行描述，然而，只要这些技术特征的组合不存在矛盾，都应当认为是本说明书记载的范围。
以上所述实施例仅表达了本申请的几种实施方式，其描述较为具体和详细，但并不能因此而理解为对专利范围的限制。应当指出的是，对于本领域的普通技术人员来说，在不脱离本申请构思的前提下，还可以做出若干变形和改进，这些都属于本申请的保护范围。因此，本申请的保护范围应以所附权利要求为准。

Claims (12)

  1. 一种光学成像系统，其特征在于，所述光学成像系统用于红外光成像，其沿着光轴由物侧至像侧依序包括：
    具有屈折力的第一透镜；
    具有屈折力的第二透镜；
    具有正屈折力的第三透镜，所述第三透镜的像侧面于圆周处为凸面；
    具有负屈折力的第四透镜；
    具有正屈折力的第五透镜，所述第五透镜的像侧面于光轴处为凹面，所述第五透镜的物侧面与像侧面均为非球面，且其物侧面和像侧面中至少一个表面包含至少一个反曲点；
    所述光学成像系统满足下列关系式：
    TT/f＜1.5；
    其中，TT为所述第一透镜物侧面至所述第五透镜像侧面在光轴上的距离，f为所述光学成像系统的有效焦距。
  2. 根据权利要求1所述的光学成像系统，其特征在于，所述光学成像系统满足下列关系式：
    0.7mm＜CT1+CT2+CT3＜1.6mm；
    其中，CT1为所述第一透镜在光轴上的厚度，CT2为所述第二透镜在光轴上的厚度，CT3为所述第三透镜在光轴上的厚度。
  3. 根据权利要求1所述的光学成像系统，其特征在于，所述光学成像系统满足下列关系式：
    0.25mm＜T12+T23+T34+T45＜0.95mm；
    其中，T12为所述第一透镜像侧面至所述第二透镜物侧面在光轴上的距离，T23为所述第二透镜像侧面至所述第三透镜物侧面在光轴上的距离，T34为所述第三透镜像侧面至所述第四透镜物侧面在光轴上的距离，T45为所述第四透镜像侧面至所述第五透镜物侧面在光轴上的距离。
  4. 根据权利要求1所述的光学成像系统，其特征在于，所述光学成像系统满足下列关系式：
    0.5＜f3/f5＜3.5；
    其中，f3为所述第三透镜的有效焦距，f5为所述第五透镜的有效焦距。
  5. 根据权利要求1所述的光学成像系统，其特征在于，所述光学成像系统满足下列关系式：
    FNO≤1.3；
    其中，FNO为所述光学成像系统的光圈数。
  6. 根据权利要求1所述的光学成像系统，其特征在于，所述光学成像 系统满足下列关系式：
    1.4＜nd1＜1.7；1.4＜nd2＜1.7；1.4＜nd4＜1.7；
    其中，nd1为所述第一透镜的折射率，nd2为所述第二透镜的折射率，nd4为所述第四透镜的折射率。
  7. 根据权利要求1所述的光学成像系统，其特征在于，所述光学成像系统满足下列关系式：
    0.85＜SD32/SD11＜1.3；
    其中，SD32为所述第三透镜像侧面的最大有效半口径，SD11为所述第一透镜物侧面的最大有效半口径。
  8. 根据权利要求1所述的光学成像系统，其特征在于，所述光学成像系统满足下列关系式：
    FFL＞0.7mm；
    其中，FFL为所述第五透镜像侧面投影于光轴上距离该透镜表面中心最远的点至所述光学成像系统成像面的距离。
  9. 根据权利要求1所述的光学成像系统，其特征在于，所述光学成像系统满足下列关系式：
    R9/R10＜1.0；
    其中，R9为所述第五透镜物侧面于光轴处的曲率半径，R10为所述第五透镜像侧面于光轴处的曲率半径。
  10. 根据权利要求1所述的光学成像系统，其特征在于，所述光学成像系统满足下列关系式：
    1.0＜|f3/R6|＜6.0；
    其中，f3为所述第三透镜的有效焦距，R6为所述第三透镜像侧面于光轴处的曲率半径。
  11. 一种取像装置，其特征在于，包括：
    如权利要求1-10任一项所述的光学成像系统；以及，
    感光元件，所述感光元件设于所述光学成像系统的像侧。
  12. 一种电子装置，其特征在于，包括：
    壳体；以及，
    如权利要求11所述的取像装置，所述取像装置安装在所述壳体上。
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160161722A1 (en) * 2014-12-08 2016-06-09 Calin Technology Co., Ltd. Imaging lens
CN206115009U (zh) * 2016-09-29 2017-04-19 广东旭业光电科技股份有限公司 一种摄像镜头和电子设备
CN107621688A (zh) * 2016-07-14 2018-01-23 今国光学工业股份有限公司 小型化广角镜头
CN208569163U (zh) * 2018-07-19 2019-03-01 浙江舜宇光学有限公司 摄像透镜系统
CN110133829A (zh) * 2019-06-17 2019-08-16 浙江舜宇光学有限公司 光学成像镜头

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160161722A1 (en) * 2014-12-08 2016-06-09 Calin Technology Co., Ltd. Imaging lens
CN107621688A (zh) * 2016-07-14 2018-01-23 今国光学工业股份有限公司 小型化广角镜头
CN206115009U (zh) * 2016-09-29 2017-04-19 广东旭业光电科技股份有限公司 一种摄像镜头和电子设备
CN208569163U (zh) * 2018-07-19 2019-03-01 浙江舜宇光学有限公司 摄像透镜系统
CN110133829A (zh) * 2019-06-17 2019-08-16 浙江舜宇光学有限公司 光学成像镜头

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