CN117492182B - Optical lens and camera module - Google Patents

Optical lens and camera module Download PDF

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Publication number
CN117492182B
CN117492182B CN202311846458.4A CN202311846458A CN117492182B CN 117492182 B CN117492182 B CN 117492182B CN 202311846458 A CN202311846458 A CN 202311846458A CN 117492182 B CN117492182 B CN 117492182B
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lens
optical lens
optical
group
substrate
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CN117492182A (en
Inventor
郭晓凡
占爽
王志强
孙大成
李忻哲
李强
刘国栋
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Lianchuang Electronic Technology Co ltd
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Lianchuang Electronic Technology Co ltd
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Classifications

    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00Optical objectives specially designed for the purposes specified below
    • G02B13/001Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras
    • G02B13/0015Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras characterised by the lens design
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00Optical objectives specially designed for the purposes specified below
    • G02B13/001Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras
    • G02B13/0015Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras characterised by the lens design
    • G02B13/002Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras characterised by the lens design having at least one aspherical surface
    • G02B13/0035Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras characterised by the lens design having at least one aspherical surface having three lenses
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00Optical objectives specially designed for the purposes specified below
    • G02B13/001Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras
    • G02B13/0055Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras employing a special optical element
    • G02B13/006Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras employing a special optical element at least one element being a compound optical element, e.g. cemented elements
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00Optical objectives specially designed for the purposes specified below
    • G02B13/18Optical objectives specially designed for the purposes specified below with lenses having one or more non-spherical faces, e.g. for reducing geometrical aberration
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B23/00Telescopes, e.g. binoculars; Periscopes; Instruments for viewing the inside of hollow bodies; Viewfinders; Optical aiming or sighting devices
    • G02B23/24Instruments or systems for viewing the inside of hollow bodies, e.g. fibrescopes
    • G02B23/2407Optical details
    • G02B23/2415Stereoscopic endoscopes
    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B23/00Telescopes, e.g. binoculars; Periscopes; Instruments for viewing the inside of hollow bodies; Viewfinders; Optical aiming or sighting devices
    • G02B23/24Instruments or systems for viewing the inside of hollow bodies, e.g. fibrescopes
    • G02B23/2407Optical details
    • G02B23/2423Optical details of the distal end
    • G02B23/243Objectives for endoscopes

Abstract

The invention discloses an optical lens and a camera module, which sequentially comprise a first group, a second group and protective glass from an object side to an imaging surface along an optical axis; the first group sequentially comprises a first substrate and a first lens which are connected in a gluing way; the second group has positive focal power and consists of a second substrate and a second lens which are connected in sequence in a gluing way; the second lens has positive optical power; a diaphragm is plated on the object side surface or the image side surface of the first substrate or the second substrate; wherein, the optical lens satisfies the conditional expression: 0.09< F/f# <0.13,0.5< F/H <0.65, F represents the effective focal length of the optical lens, f# represents the aperture value of the optical lens, and H represents the image height corresponding to the maximum field angle of the optical lens. The optical lens provided by the invention reduces the size and caliber of the lens while meeting the requirement of a large field angle, effectively increases the depth of field of the lens, and can well meet the requirements of the detection range and the observation depth of an endoscope.

Description

Optical lens and camera module
Technical Field
The present invention relates to the field of optical imaging technology, and in particular, to an optical lens and an imaging module.
Background
In recent years, with the rapid development of the medical field, the requirements of society on medical equipment are increasing, and in particular, the requirements on the performance of cameras mounted on medical detection equipment are increasing, for example, in order to more flexibly and comprehensively enter a human body to collect images, medical equipment such as an endoscope and the like carrying an imaging lens is generally adopted to perform the examination of various intracavity diseases such as gastrointestinal tract, pancreas, biliary tract, respiratory tract and the like so as to determine the internal structure of the human body or observe pathological states.
Currently, in the market, endoscope lenses generally have problems of oversized size, small angle of view and insufficient depth of field, such as: the oversized endoscope can cause discomfort to a human body when the endoscope is used, the small angle of view can cause the scope of observation of the endoscope lens to be insufficient, and the small depth of field can influence the depth of observation of the endoscope lens.
Disclosure of Invention
Therefore, the invention aims to provide an optical lens and an imaging module, which at least have the characteristics of small size, small caliber, large field of view and large depth of field.
The embodiment of the invention realizes the aim through the following technical scheme.
In one aspect, the present invention provides an optical lens, which sequentially comprises a first group, a second group, and a protective glass from an object side to an imaging surface along an optical axis; the first group sequentially comprises a first substrate and a first lens which are connected in a gluing way from the object side to the imaging surface along the optical axis; the second group has positive focal power and consists of a second substrate and a second lens which are connected in a gluing way in sequence from the object side to the imaging surface along the optical axis; the second lens has positive optical power; a diaphragm is plated on the object side surface or the image side surface of the first substrate or the second substrate; wherein, the optical lens satisfies the conditional expression: 0.09< F/f# <0.13,0.5< F/H <0.65, F represents the effective focal length of the optical lens, f# represents the aperture value of the optical lens, and H represents the image height corresponding to the maximum field angle of the optical lens.
In some embodiments, the first group further includes a third lens, and an image side surface of the third lens is glued to an object side surface of the first substrate; the third lens has negative optical power.
In some embodiments, the image side of the second lens is convex and the object side of the third lens is concave.
In some embodiments, the optical lens satisfies the following conditional expression: 0.1< R1/R8<3, wherein R1 represents a radius of curvature of an object side surface of the third lens and R8 represents a radius of curvature of an image side surface of the second lens.
In some implementations, the first group has negative optical power, and the optical lens satisfies the conditional expression: -5<f Q1/f < -1 > wherein f Q1 represents the effective focal length of the first group and f represents the effective focal length of the optical lens.
In some implementations, the first group has positive optical power, and the optical lens satisfies the conditional expression: 0.9< f Q1/f <1.5, wherein f Q1 represents an effective focal length of the first group and f represents an effective focal length of the optical lens.
In some embodiments, the means for glue bonding includes nano-imprinting means or etching means.
In some embodiments, the optical lens satisfies the following conditional expression: 0.6< f Q2/f <16, where f Q2 represents an effective focal length of the second group and f represents an effective focal length of the optical lens.
In some embodiments, the optical lens satisfies the following conditional expression: -4<f Q1/fQ2 <0.2, where f Q1 represents the effective focal length of the first group and f Q2 represents the effective focal length of the second group.
In some embodiments, the optical lens satisfies the following conditional expression: 1< CT Q1/CTQ2<3,0.25mm<CTQ1<0.5mm,0.1mm<CTQ2 <0.4mm, wherein CT Q1 represents the central thickness of the first group on the optical axis and CT Q2 represents the central thickness of the second group on the optical axis.
In some embodiments, the optical lens satisfies the following conditional expression: 1.1mm/rad < TTL/θ <1.8mm/rad, wherein TTL represents the distance from the object side surface to the imaging surface of the first group on the optical axis, and θ represents the maximum half field angle of the optical lens.
On the other hand, the invention also provides an image pickup module, which comprises the optical lens and the imaging element, wherein the imaging element is used for converting an optical image formed by the optical lens into an electric signal.
Compared with the prior art, the optical lens provided by the invention adopts two groups of lens groups formed by bonding the substrate and the lens, and the focal power and the surface type collocation of each lens group are reasonably arranged, so that the lens size and caliber are reduced to a certain extent while the large angle of view is met, the depth of field of the lens is effectively increased, and the requirements of the endoscope on the detection range and the observation depth can be well met.
Drawings
The foregoing and/or additional aspects and advantages of the present invention will be apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings.
Fig. 1 is a schematic structural diagram of an optical lens according to a first embodiment of the present invention;
FIG. 2 is a graph showing a field curvature of an optical lens according to a first embodiment of the present invention;
FIG. 3 is a graph showing the MTF of an optical lens according to a first embodiment of the present invention;
FIG. 4 is a graph showing axial chromatic aberration of an optical lens according to a first embodiment of the present invention;
FIG. 5 is a schematic diagram of an optical lens according to a second embodiment of the present invention;
FIG. 6 is a graph showing a field curvature of an optical lens according to a second embodiment of the present invention;
FIG. 7 is a graph showing the MTF of an optical lens according to a second embodiment of the present invention;
FIG. 8 is a graph showing axial chromatic aberration of an optical lens according to a second embodiment of the present invention;
FIG. 9 is a schematic diagram of an optical lens according to a third embodiment of the present invention;
FIG. 10 is a graph showing a field curvature of an optical lens according to a third embodiment of the present invention;
FIG. 11 is a graph showing the MTF of an optical lens according to a third embodiment of the present invention;
FIG. 12 is a graph showing axial chromatic aberration of an optical lens according to a third embodiment of the present invention;
fig. 13 is a schematic structural diagram of an optical lens according to a fourth embodiment of the present invention.
Detailed Description
In order that the objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Several embodiments of the invention are presented in the figures. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Like reference numerals refer to like elements throughout the specification.
Furthermore, the terms "first," "second," "third," and the like, are used primarily to distinguish between different devices, elements or components (the particular species and configurations may be the same or different), and are not used to indicate or imply relative importance and amounts of the indicated devices, elements or components.
In this context, near the optical axis means the area near the optical axis. If the lens surface is convex and the convex position is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the concave position is not defined, it means that the lens surface is concave at least in the paraxial region.
The invention provides an optical lens which sequentially comprises a first group, a second group and protective glass from an object side to an imaging surface along an optical axis.
The first group has negative focal power or positive focal power, and sequentially comprises a first substrate and a first lens which are connected in a gluing way from the object side to the imaging surface along the optical axis; the surface of the first lens, which is glued with the first substrate, is a plane; in some embodiments, the first group further includes a third lens, and an image side surface of the third lens is glued to an object side surface of the first substrate; lenses are respectively arranged on the two surfaces of the first substrate, so that high-quality imaging of the lens can be better ensured. The surfaces of the first lens and the third lens, which are glued with the first substrate, are plane surfaces; specifically, the third lens has negative focal power, and the object side surface of the third lens is a concave surface.
The second group has positive focal power and sequentially comprises a second substrate and a second lens which are connected in a gluing way from the object side to the imaging surface along the optical axis; the second lens is glued on the image side surface of the second substrate; the surface of the second lens glued with the second substrate is a plane. The second lens has positive optical power; the image side surface of the second lens is a convex surface.
The first substrate and the second substrate can be glass substrates or plastic substrates with certain thickness and width, and the width (effective caliber) of the first substrate and the second substrate in the direction perpendicular to the optical axis is larger than the effective caliber of the glued lens, so that a stable forming environment can be provided for each lens, and meanwhile connection and assembly among different subsequent groups are facilitated.
More specifically, the thicknesses of the first substrate and the second substrate can be selected to be 0.05mm-0.3mm, the maximum effective caliber of the first substrate and the second substrate is smaller than 1.1mm, but the effective calibers of the first substrate and the second substrate are larger than the effective calibers of the lenses, so that the first substrate and the second substrate have better supporting and stabilizing effects for the lenses.
The lenses are connected with the substrate in a gluing mode, specifically, the first lens, the second lens and the third lens can be fixed on the first substrate and the second substrate in a nano imprinting or etching mode, so that the processing precision and the stability of the lenses can be ensured, and the miniaturization of the optical lens is realized.
The optical lens adopts a processing mode of stamping or etching a lens structure on the first glass or the second glass or the plastic substrate, and can realize wide angle and miniaturization of the lens and ensure that the lens has the characteristic of large depth of field. Preferably, the first lens, the second lens and the third lens all adopt a photoresist imprinting mode, the glued surface of the lens and the substrate is a plane, the surface of the lens far away from the substrate can be a spherical surface or an aspherical surface, and an aspherical lens is preferably adopted, so that the manufacturing cost can be effectively reduced, the weight is reduced, more excellent imaging effect can be provided, and the optical performance is more excellent.
The diaphragm is plated on the object side surface or the image side surface of the first substrate or the second substrate, and the diaphragm limits the aperture of the size of the incident light beam, so that the size and the position of the diaphragm have decisive effects on the definition, the imaging range and the brightness of the imaging of the lens. In order to better control the intensity of the incident light, a diaphragm is arranged on the object side surface or the image side surface of the first substrate or the second substrate in a film plating mode, and the gluing effect of the lens and the first substrate or the second substrate is not affected because the diaphragm film layer is very thin. In order to better play a role in converging the incident light, the effective aperture value of the diaphragm is set to be smaller, for example, may be 0.1mm or 0.12mm,0.15mm or other values, and the setting is specifically performed according to the actual situation, and the embodiment is not limited specifically.
Because the optical lens provided by the invention has smaller overall size, the processing difficulty of a single lens and the lens assembly are larger according to the conventional mode, and the processing precision cannot be ensured, the first substrate and the second substrate have larger widths through arranging the lenses on the first substrate and the second substrate in a gluing way, so that a stable supporting effect can be provided for the positions of the lenses, and meanwhile, the first substrate and the second substrate only need to be installed and fixed according to the preset space during the lens assembly, the respective installation errors among a plurality of lenses do not need to be considered, the overall processing sensitivity is reduced, and the processability of the lens is improved.
In some embodiments, the optical lens satisfies the following conditional expression: 0.09< F/f# <0.13,0.5< F/H <0.65, wherein F represents an effective focal length of the optical lens, f# represents an aperture value of the optical lens, and H represents an image height corresponding to a maximum field angle of the optical lens. The optical lens has a large enough depth of field range and a large image surface, can realize clear imaging on the image surface when the object distance is 5mm to infinity, and is beneficial to increasing the observation depth and detection range of the lens in the use process.
In some embodiments, the optical lens satisfies the following conditional expression: 0.1< R1/R8<3, wherein R1 represents a radius of curvature of an object side surface of the third lens and R8 represents a radius of curvature of an image side surface of the second lens. The lens has the advantages that the surface type collocation of the head lens and the tail lens in the lens is reasonably controlled, so that the aberration of the lens is better corrected and the overall imaging quality of the lens is improved while the large view field of the lens is realized.
In some implementations, the first group has negative optical power, and the optical lens satisfies the conditional expression: -5<f Q1/f < -1 > wherein f Q1 represents the effective focal length of the first group and f represents the effective focal length of the optical lens. The first group has larger negative refractive power, is favorable for collecting incident light in a large view field range, increases the view angle of the lens, and realizes a larger observation range.
In some implementations, the first group has positive optical power, and the optical lens satisfies the conditional expression: 0.9< f Q1/f <1.5, wherein f Q1 represents an effective focal length of the first group and f represents an effective focal length of the optical lens. The first group has larger positive refractive power, is favorable for collecting incident light in a large view field range, increases the view angle of the lens, and realizes a larger observation range.
In some embodiments, the optical lens satisfies the following conditional expression: 0.9< f Q2/f <15, where f Q2 represents an effective focal length of the second group and f represents an effective focal length of the optical lens. The second group has reasonable positive focal power, so that the aberration brought by the first group can be better corrected, meanwhile, the correction difficulty of the distortion of the marginal field of view is reduced, and the overall imaging quality is improved.
In some embodiments, the optical lens satisfies the following conditional expression: -4<f Q1/fQ2 <0.2, where f Q1 represents the effective focal length of the first group and f Q2 represents the effective focal length of the second group. The lens has the advantages that the focal power collocation of the first group and the second group is reasonably set, the incident angle of light can be properly increased, the angle of light incident on an image surface can be effectively controlled, the lens is ensured to have a larger angle of view, meanwhile, large image surface imaging is realized, and the balancing of wide angle and high-quality imaging of the lens is realized.
In some embodiments, the optical lens satisfies the following conditional expression: 1< CT Q1/CTQ2<3,0.25mm<CTQ1<0.5mm,0.1mm<CTQ2 <0.4mm, wherein CT Q1 represents the central thickness of the first group on the optical axis and CT Q2 represents the central thickness of the second group on the optical axis. The thickness of each group is reasonably set, so that miniaturization of the lens is realized, meanwhile, lens forming and assembly are facilitated, and the product yield is ensured.
In some embodiments, the optical lens satisfies the following conditional expression: 0.4< D/H <1.1,0.9mm < H <1mm, wherein D represents the maximum effective caliber in the first substrate and the second substrate, and H represents the image height corresponding to the maximum field angle of the optical lens. The lenses are respectively glued on the first substrate and the second substrate, and the effective caliber of each lens is smaller than that of each substrate, so that the conditions are met, the lens is ensured to have smaller external caliber and smaller volume, the field angle of the lens is increased, the imaging range of the lens is enlarged, and the larger observation range is realized. In some embodiments, the apertures of the first substrate and the second substrate are equal, which is beneficial to processing and assembling the components of each group (including the substrate and the lens) into the lens, and improves the assembly yield.
In some embodiments, the optical lens satisfies the following conditional expression: 1.1mm/rad < TTL/θ <1.8mm/rad, wherein TTL represents the distance from the object side surface to the imaging surface of the first group on the optical axis, and θ represents the maximum half field angle of the optical lens. The optical lens has smaller total optical length and larger angle of view and larger imaging surface, and can realize the balance of small size, large visual angle and high pixels.
In some embodiments, the maximum field angle of the optical lens is 112 ° < FOV <130 °, and the total optical length of the optical lens is 1.1mm < ttl <2.0 mm.
The optical lens provided by the invention adopts two groups of lens groups glued by the substrate and the lens, and by reasonably setting the focal power and the surface type collocation of each lens group, the lens has a large field angle (FOV can reach 120 degrees) and smaller total length, and simultaneously the depth of field of the lens is effectively increased, so that the lens can realize high-definition imaging in 5mm to infinite working object distance, and the requirements of the endoscope detection range, observation depth and definition can be well met.
In the embodiments of the present invention, when the lens surface type in the optical lens is an aspherical surface, the aspherical surface type of each lens satisfies the following equation:
Where z is the distance sagittal height from the aspherical surface vertex when the aspherical surface is at a position of height h in the optical axis direction, c is the paraxial curvature of the surface, k is a quadric surface coefficient, and a 2i is an aspherical surface type coefficient of 2 i-th order.
The invention is further illustrated in the following examples. In various embodiments, the thickness, radius of curvature, and material selection portion of each lens in the optical lens may vary, and for specific differences, reference may be made to the parameter tables of the various embodiments. The following examples are merely preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following examples, and any other changes, substitutions, combinations or simplifications that do not depart from the gist of the present invention are intended to be equivalent substitutes within the scope of the present invention.
First embodiment
Referring to fig. 1, a schematic structural diagram of an optical lens 100 according to a first embodiment of the present invention is shown, where the optical lens 100 includes, in order from an object side to an imaging plane along an optical axis: a first group Q1 having negative power, a second group Q2 having positive power, and a cover glass G3.
The first group Q1 includes, in order from the object side to the imaging plane along the optical axis, a first substrate G1 and a first lens L1. The thickness of the first substrate G1 in the optical axis direction is 0.210mm, and the object side surface S2 and the image side surface S3 of the first substrate G1 are both planar. The first lens L1 has negative optical power, the object-side surface of the first lens L1 is a plane, the image-side surface S4 is a concave surface, and the object-side surface of the first lens L1 is glued on the image-side surface S3 of the first substrate G1 by nano imprinting.
The second group Q2 includes a second substrate G2 and a second lens L2 in order from the object side to the imaging surface along the optical axis. The thickness of the second substrate G2 in the optical axis direction is 0.175mm, and the object side surface S6 and the image side surface S7 of the second substrate G2 are both planar. The second lens L2 has positive optical power, the object-side surface of the second lens L2 is a plane, the image-side surface S8 is a convex surface, and the object-side surface of the second lens L2 is glued on the image-side surface S7 of the second substrate G2 by nano imprinting. The diaphragm ST is plated on the image side surface S7 of the second substrate G2 in a film plating mode, and the effective caliber of the diaphragm ST is 0.12mm.
The thickness of the cover glass G3 in the optical axis direction is 0.358mm, and the object side surface S9 and the image side surface S10 of the cover glass G3 are both flat surfaces for protecting the imaging chip.
The first substrate G1, the second substrate G2 and the protective glass G3 are made of glass materials, so that imprinting of the lens and assembly of the lens can be better realized.
The image side surface S4 of the first lens L1 and the image side surface S8 of the second lens L2 are aspherical surfaces. The first lens L1 and the second lens L2 are made of plastic materials which are convenient to produce, so that the nanoimprint lens is convenient to form on one hand, and the volume and the weight of the lens can be reduced on the other hand.
The relevant parameters of each lens in the optical lens 100 provided in this embodiment are shown in table 1.
TABLE 1
The surface profile coefficients of the aspherical surfaces of the optical lens 100 in this embodiment are shown in table 2.
TABLE 2
In the present embodiment, graphs of curvature of field, MTF, and axial chromatic aberration of the optical lens 100 are shown in fig. 2, 3, and 4, respectively.
In fig. 2, the field Qu Quxian represents the field curvature of the meridian direction and the sagittal direction at different image heights of the image plane, the horizontal axis represents the offset (unit: mm) in the figure, and the vertical axis represents the angle of view (unit: degree), and the field curvature offset of the meridian direction and the sagittal direction at the image plane is controlled within ±0.10mm, which indicates that the field curvature of the optical lens 100 is well corrected.
In fig. 3, the MTF curve represents the degree of modulation of lens imaging at a frequency of 75lp/mm at different fields of view, the horizontal axis represents the angle of view (in degrees), and the vertical axis represents the MTF value. As can be seen from the figure, the MTF values of the optical lens 100 in the present embodiment are all above 0.5 in the full field of view, and the MTF curves are approximately horizontal in the process from the center to the edge field of view, which indicates that the optical lens 100 has better imaging quality and better detail resolution under the full field of view.
The axial chromatic aberration curves of fig. 4 represent aberrations at different wavelengths on the optical axis at the imaging plane, with the horizontal axis representing the offset (in millimeters) and the vertical axis representing the normalized pupil radius. As can be seen from the figure, the shift amount of the axial chromatic aberration is controlled within ±0.07 millimeters, indicating that the optical lens 100 can effectively correct the aberration of the fringe field of view.
Second embodiment
Referring to fig. 5, a schematic diagram of an optical lens 200 according to a second embodiment of the present invention is shown, and the optical lens 200 in the present embodiment is substantially the same as the optical lens 100 in the first embodiment in that the first group Q1 further includes a third lens L3, the first group Q1 has positive optical power, and the curvature radius, the aspheric coefficient, the thickness of the substrate, etc. of each lens surface are different. Specifically, the optical lens 200 includes, in order from an object side to an imaging surface along an optical axis: a first group Q1 having positive optical power, a second group Q2 having positive optical power, and a cover glass G3.
The first group Q1 includes, in order from the object side to the imaging plane along the optical axis, a third lens L3, a first substrate G1, and a first lens L1. The thickness of the first substrate G1 in the optical axis direction is 0.075mm, and the object side surface S2 and the image side surface S3 of the first substrate G1 are both planar. The third lens L3 has negative focal power, the object side surface S1 of the third lens L3 is a concave surface, and the image side surface is a plane; the first lens element L1 has positive refractive power, an object-side surface of the first lens element L1 is a plane, an image-side surface S4 is a convex surface, and an image-side surface of the third lens element L3 and the object-side surface of the first lens element L1 are bonded to the object-side surface S2 and the image-side surface S3 of the first substrate G1 by nanoimprinting. The diaphragm ST is plated on the object side surface S2 of the first substrate G1 by a plating method, and the bonding effect between the third lens L3 and the first substrate G1 is not affected due to the thin diaphragm film layer.
The second group Q2 includes a second substrate G2 and a second lens L2 in order from the object side to the imaging surface along the optical axis. The thickness of the second substrate G2 in the optical axis direction is 0.082mm, and the object side surface S6 and the image side surface S7 of the second substrate G2 are both planar. The second lens L2 has positive focal power, the object side surface of the second lens L2 is a plane, and the image side surface S8 is a convex surface; the object side surface of the second lens L2 is glued on the image side surface S7 of the second substrate G2 by nano-imprinting.
The thickness of the cover glass G3 in the optical axis direction is 0.3mm, and the object side surface S9 and the image side surface S10 of the cover glass G3 are both flat surfaces for protecting the imaging chip.
The first substrate G1 and the second substrate G2 are made of glass, so that imprinting of the lens and assembly of the lens can be better realized.
The image side surface S4 of the first lens element L1, the image side surface S8 of the second lens element L2, and the object side surface S1 of the third lens element L3 are aspheric. The first lens L1, the second lens L2 and the third lens L3 are made of plastic materials which are convenient to produce, so that the nanoimprint lens is convenient to form on one hand, and the volume and the weight of the lens can be reduced on the other hand.
The relevant parameters of each lens in the optical lens 200 provided in this embodiment are shown in table 3.
TABLE 3 Table 3
The surface profile coefficients of the aspherical surfaces of the optical lens 200 in this embodiment are shown in table 4.
TABLE 4 Table 4
In the present embodiment, graphs of curvature of field, MTF, and axial chromatic aberration of the optical lens 200 are shown in fig. 6, 7, and 8, respectively.
As can be seen from fig. 6, the curvature of field offset in the meridian direction and the sagittal direction at the image plane are controlled within ±0.04 mm, which indicates that the curvature of field of the optical lens 200 is well corrected.
As can be seen from fig. 7, the MTF values of the optical lens 200 in the present embodiment are all above 0.6 in the full field of view, and the MTF curves are approximately horizontal in the process from the center to the edge field of view at the frequency of 75lp/mm, which indicates that the optical lens 200 has better imaging quality and better detail resolution in the full field of view.
As can be seen from fig. 8, the offset amount of the axial chromatic aberration is controlled within ±0.05 mm, indicating that the optical lens 200 can effectively correct the aberration of the fringe field of view.
Third embodiment
Referring to fig. 9, a schematic diagram of an optical lens 300 according to a third embodiment of the present invention is shown, and the optical lens 300 in the present embodiment is substantially the same as the optical lens 200 in the second embodiment, except that the first group Q1 has negative optical power, the diaphragm ST is disposed on the image side surface S7 of the second substrate G2, and the curvature radius, the aspheric coefficient, the thickness of the substrate, and the like of each lens surface are different. Specifically, the optical lens 300 includes, in order from the object side to the imaging plane along the optical axis: a first group Q1 having negative optical power, a second group Q2 having positive optical power, and a cover glass G3.
The first group Q1 includes, in order from the object side to the imaging plane along the optical axis, a third lens L3, a first substrate G1, and a first lens L1. The object side surface S2 and the image side surface S3 of the first substrate G1 are both planar. The third lens L3 has negative focal power, the object side surface S1 of the third lens L3 is a concave surface, and the image side surface is a plane; the first lens element L1 has positive refractive power, an object-side surface of the first lens element L1 is a plane, an image-side surface S4 is a convex surface, and an image-side surface of the third lens element L3 and the object-side surface of the first lens element L1 are bonded to the object-side surface S2 and the image-side surface S3 of the first substrate G1 by nanoimprinting.
The second group Q2 includes a second substrate G2 and a second lens L2 in order from the object side to the imaging surface along the optical axis. The thickness of the second substrate G2 in the optical axis direction is 0.210mm, and the object side surface S6 and the image side surface S7 of the second substrate G2 are both planar. The second lens L2 has positive focal power, the object side surface of the second lens L2 is a plane, and the image side surface S8 is a convex surface; the object side surface of the second lens L2 is glued on the image side surface S7 of the second substrate G2 by nano-imprinting. The diaphragm ST is coated on the image side surface S7 of the second substrate G2 by a film coating method, and the bonding effect between the second lens L2 and the second substrate G2 is not affected due to the thin diaphragm film layer.
The thickness of the cover glass G3 in the optical axis direction is 0.3mm, and the object side surface S9 and the image side surface S10 of the cover glass G3 are both flat surfaces for protecting the imaging chip.
The first substrate G1 and the second substrate G2 are made of glass, so that imprinting of the lens and assembly of the lens can be better realized.
The image side surface S4 of the first lens element L1, the image side surface S8 of the second lens element L2, and the object side surface S1 of the third lens element L3 are aspheric. The first lens L1, the second lens L2 and the third lens L3 are made of plastic materials which are convenient to produce, so that the nanoimprint lens is convenient to form on one hand, and the volume and the weight of the lens can be reduced on the other hand.
The relevant parameters of each lens in the optical lens 300 provided in this embodiment are shown in table 5.
TABLE 5
The surface profile coefficients of the aspherical surfaces of the optical lens 300 in this embodiment are shown in table 6.
TABLE 6
In the present embodiment, graphs of curvature of field, MTF, and axial chromatic aberration of the optical lens 300 are shown in fig. 10, 11, and 12, respectively.
As can be seen from fig. 10, the curvature of field offset in the meridian direction and the sagittal direction at the image plane are both controlled within ±0.05 mm, indicating that the curvature of field of the optical lens 300 is well corrected.
As can be seen from fig. 11, the MTF values of the optical lens 300 in the present embodiment are all above 0.55 in the full field of view, and the MTF curves are approximately horizontal in the process from the center to the edge field of view at the frequency of 75lp/mm, which indicates that the optical lens 300 has better imaging quality and better detail resolution in the full field of view.
As can be seen from fig. 12, the offset amount of the axial chromatic aberration is controlled within ±0.06 millimeters, indicating that the optical lens 300 can effectively correct the aberration of the fringe field of view.
Referring to table 7, the correlation values of the optical lens provided in the above three embodiments and each of the above conditional expressions are shown.
TABLE 7
Fourth embodiment
Referring to fig. 13, a fourth embodiment of the present invention provides an image capturing module 400, where the image capturing module 400 may include an imaging element 410 and an optical lens (e.g., the optical lens 300) according to any of the above embodiments. The imaging element 410 may be a CMOS (Complementary Metal Oxide Semiconductor ) image sensor or a CCD (Charge Coupled Device, charge coupled device) image sensor.
The image pickup module 400 may be any of a medical endoscope, an industrial endoscope, a capsule lens, and a camera equipped with the optical lens according to any of the above embodiments.
The image capturing module 400 provided in this embodiment includes the optical lens in any of the above embodiments, and because of the characteristics of small size, small caliber and large field of view of the optical lens, the image capturing module 400 with the optical lens also has the advantages of small size, small caliber and large field of view, and can well meet the requirements of the endoscope on the detection range and the observation depth.
In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The foregoing examples illustrate only a few embodiments of the invention and are described in detail herein without thereby limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.

Claims (11)

1. An optical lens is characterized by comprising a first group, a second group and protective glass in sequence from an object side to an imaging surface along an optical axis;
The first group sequentially comprises a first substrate and a first lens which are connected in a gluing way from the object side to the imaging surface along the optical axis;
the second group has positive focal power and consists of a second substrate and a second lens which are connected in a gluing way in sequence from the object side to the imaging surface along the optical axis; the second lens has positive optical power;
a diaphragm is plated on the object side surface or the image side surface of the first substrate or the second substrate;
Wherein, the optical lens satisfies the conditional expression: 0.09< F/f# <0.13,0.5< F/H <0.65, F represents the effective focal length of the optical lens, f# represents the aperture value of the optical lens, and H represents the image height corresponding to the maximum field angle of the optical lens;
the optical lens satisfies the following conditional expression: -4<f Q1/fQ2 <0.2, where f Q1 represents the effective focal length of the first group and f Q2 represents the effective focal length of the second group.
2. The optical lens of claim 1, wherein the first group further comprises a third lens, and an image side surface of the third lens is bonded to an object side surface of the first substrate; the third lens has negative optical power.
3. The optical lens of claim 2, wherein the second lens element has a convex image-side surface and the third lens element has a concave object-side surface.
4. The optical lens according to claim 2, wherein the optical lens satisfies a conditional expression: 0.1< R1/R8<3, wherein R1 represents a radius of curvature of an object side surface of the third lens and R8 represents a radius of curvature of an image side surface of the second lens.
5. The optical lens of claim 1, wherein the first group has negative optical power and the optical lens satisfies the conditional expression: -5<f Q1/f < -1 > wherein f Q1 represents the effective focal length of the first group and f represents the effective focal length of the optical lens.
6. The optical lens of claim 1, wherein the first group has positive optical power and the optical lens satisfies the conditional expression: 0.9< f Q1/f <1.5, wherein f Q1 represents an effective focal length of the first group and f represents an effective focal length of the optical lens.
7. The optical lens of claim 1, wherein the glue joint comprises a nanoimprint or an etching.
8. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 0.6< f Q2/f <16, where f Q2 represents an effective focal length of the second group and f represents an effective focal length of the optical lens.
9. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 1< CT Q1/CTQ2<3,0.25mm<CTQ1<0.5mm,0.1mm<CTQ2 <0.4mm, wherein CT Q1 represents the central thickness of the first group on the optical axis and CT Q2 represents the central thickness of the second group on the optical axis.
10. The optical lens according to claim 1, wherein the optical lens satisfies a conditional expression: 1.1mm/rad < TTL/θ <1.8mm/rad, wherein TTL represents the distance from the object side surface to the imaging surface of the first group on the optical axis, and θ represents the maximum half field angle of the optical lens.
11. An imaging module comprising the optical lens of any one of claims 1-10 and an imaging element for converting an optical image formed by the optical lens into an electrical signal.
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010266816A (en) * 2009-05-18 2010-11-25 Konica Minolta Opto Inc Imaging lens, image capturing apparatus and mobile terminal
JP2010266815A (en) * 2009-05-18 2010-11-25 Konica Minolta Opto Inc Imaging lens, image capturing apparatus and mobile terminal
WO2010146899A1 (en) * 2009-06-16 2010-12-23 コニカミノルタオプト株式会社 Image taking lens, image taking device, and portable terminal
CN116009221A (en) * 2023-03-24 2023-04-25 联创电子科技股份有限公司 Optical lens and camera module
CN116009214A (en) * 2023-03-24 2023-04-25 联创电子科技股份有限公司 Optical lens and camera module
CN116009220A (en) * 2023-03-24 2023-04-25 联创电子科技股份有限公司 Optical lens and camera module
WO2023143239A1 (en) * 2022-01-27 2023-08-03 江西联创电子有限公司 Optical lens

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010266816A (en) * 2009-05-18 2010-11-25 Konica Minolta Opto Inc Imaging lens, image capturing apparatus and mobile terminal
JP2010266815A (en) * 2009-05-18 2010-11-25 Konica Minolta Opto Inc Imaging lens, image capturing apparatus and mobile terminal
WO2010146899A1 (en) * 2009-06-16 2010-12-23 コニカミノルタオプト株式会社 Image taking lens, image taking device, and portable terminal
WO2023143239A1 (en) * 2022-01-27 2023-08-03 江西联创电子有限公司 Optical lens
CN116009221A (en) * 2023-03-24 2023-04-25 联创电子科技股份有限公司 Optical lens and camera module
CN116009214A (en) * 2023-03-24 2023-04-25 联创电子科技股份有限公司 Optical lens and camera module
CN116009220A (en) * 2023-03-24 2023-04-25 联创电子科技股份有限公司 Optical lens and camera module

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