Imaging lens

Abstract

The present invention relates to an imaging lens, comprising a lens barrel (1) and an optical system (2) arranged in the lens barrel (1), wherein the optical system (2) comprises at least a first lens (21) and a second lens (22) arranged in sequence from the object side to the image side along an optical axis, wherein the outer edges of the first lens (21) and the second lens (22) bear against the inner wall of the lens barrel (1), a spacer (23) is provided between the first lens (21) and the second lens (22), and an annular blocking protrusion (231) extending axially toward the object side is provided on the outer edge of the object side of the spacer (23), and the outer diameter surface of the first lens (21) and the inner annular surface of the blocking protrusion (231) abut against each other. The spacer in the imaging lens of the present invention can effectively resist the overturning moment applied by the lens, thereby making the overall stability of the lens higher.

Description

Technical Field

[0001] The present invention relates to a lens, and in particular to an imaging lens with a spacer. Background Art

[0002] Due to the high image quality offered by high-pixel mobile phone lenses, they are increasingly popular. Continuously increasing the image sensor image size has become a major research focus within this field. To accommodate the large image sensor size, the diameter of the lenses adjacent to the image sensor has also increased. Typically, two lens groups with a significant diameter difference are connected by a spacer of a certain thickness, each supported by two parallel end faces. A larger difference in diameter between this lens and the outermost lens of the mobile phone lens means a larger spacing between the spacer bearing surfaces between the lenses, resulting in a correspondingly greater tilting torque and reduced structural stability. This, in turn, leads to reduced reliability and yield. Furthermore, in high-temperature and high-humidity environments, due to the varying expansion coefficients of the various lens component materials, the lens barrel can shorten or lengthen relative to the lens, spacers (light shielding plates), retaining rings, and other components along the lens' optical axis. As the lens barrel shortens, the spacers between the lenses may collapse, causing permanent deformation. This can significantly reduce lens performance after the temperature and humidity return to normal. As the lens barrel lengthens, the lenses may lose their compressive force along the optical axis, shifting the relative phases between the lenses. This can also significantly reduce lens performance after the temperature and humidity return to normal. Therefore, conventional mobile phone lenses with conventional spacer structures suffer from the problem of spacer stability affecting lens quality.

[0003] For example, Figure 11 The prior art lens shown includes a lens barrel 101, a first lens 102, and a second lens 104 located therein, with a spacer 103 interposed between the two lenses. However, the spacer 103 in this embodiment lacks any design to provide radial support relative to the first lens 102, and thus cannot effectively resist the tilting moment exerted by the lens on the spacer 103, resulting in poor overall stability of the lens. Summary of the Invention

[0004] The purpose of the present invention is to solve the above-mentioned problem and provide an imaging lens.

[0005] To achieve the above-mentioned object of the invention, the present invention provides an imaging lens, comprising a lens barrel and an optical system arranged in the lens barrel, the optical system comprising at least a first lens and a second lens arranged in sequence from the object side to the image side along the optical axis, the outer edges of the first lens and the second lens resting on the inner wall of the lens barrel, a spacer is provided between the first lens and the second lens, the object-side outer edge of the spacer is provided with an annular blocking protrusion extending axially toward the object side, the outer diameter surface of the first lens and the inner annular surface of the blocking protrusion abut against each other.

[0006] According to one aspect of the present invention, a first annular abutting protrusion is provided on the image side of the first lens, and the first abutting protrusion abuts against the object side of the spacer in an assembled state.

[0007] According to one aspect of the present invention, a second annular abutting protrusion is provided on the object side of the spacer, and the second abutting protrusion abuts against the image side of the first lens in the assembled state.

[0008] According to one aspect of the present invention, the height of the abutting protrusion is greater than 5 micrometers.

[0009] According to one aspect of the present invention, a pre-tightening groove is provided on the object side of the spacer, which is composed of an inner groove wall and an outer groove wall, wherein the inner groove wall is a conical surface and the outer groove wall is a cylindrical surface;

[0010] The inner groove wall and the outer groove wall form an acute angle.

[0011] According to one aspect of the present invention, the bottom of the pre-tightening groove is provided with an annular reinforcement protrusion extending axially toward the object side.

[0012] According to one aspect of the present invention, the inner side wall of the reinforcing protrusion is a cylindrical surface, and the object side wall is an annular plane.

[0013] According to one aspect of the present invention, a supporting conical surface is provided on the outer edge of the spacer, and the angle θ1 between the supporting conical surface and the optical axis is an acute angle;

[0014] The lens barrel has a conical inner wall close to the spacer and can be matched with the supporting conical surface.

[0015] According to one aspect of the present invention, the supporting conical surface is parallel to the inner wall of the conical surface or the angle difference between them is no more than 2°.

[0016] According to one aspect of the present invention, the cone angle of the supporting cone surface is smaller than or equal to the cone angle of the inner wall of the cone surface.

[0017] According to one aspect of the present invention, there is a gap between the outer edge of the spacer and the inner wall of the lens barrel or the spacer rests on the inner wall of the lens barrel.

[0018] According to one aspect of the present invention, the inner non-supporting portion of the image side of the spacer is a conical surface, and the angle θ2 between the inner non-supporting portion and the object side supporting surface of the spacer is an acute angle.

[0019] According to one aspect of the present invention, the height of the blocking protrusion is greater than one fifth of the axial width of the outer side surface of the first lens.

[0020] According to one aspect of the present invention, a light shielding structure is further included, which is a light shielding plate located between the spacer and the second lens, or a ring-shaped light shielding protrusion extending from the image side of the spacer.

[0021] According to the present invention, a blocking protrusion is provided on the outer edge of the imaging lens spacer. Its annular shape creates a groove within which the outer edge of the first lens rests. This effectively resists the tipping moment exerted by the lens on the spacer, thereby stabilizing the overall lens structure. This improves mobile phone reliability through the lens spacer's design of varying degrees of freedom and adjustable stiffness.

[0022] According to one solution of the present invention, an annular abutment protrusion is provided on the first lens or the spacer, so that the spacer and the first lens are connected axially through the abutment protrusion, thereby ensuring that the axial force transmitted between the two is in a straight line, avoiding the generation of corresponding bending moment that affects the overall imaging quality of the lens.

[0023] According to one solution of the present invention, a pre-tightening groove is provided on the object side of the spacer, and the pre-tightening groove is composed of an inner and an outer groove wall, wherein the inner groove wall is a conical surface and the outer groove wall is a cylindrical surface, thereby making the inner part of the spacer have a strong elasticity, and being able to provide a pre-tightening force and a large deformation amount along the optical axis for the first lens, and forming a reliable axial pressing force in a high temperature and high humidity environment.

[0024] According to one solution of the present invention, an additional reinforcing protrusion is provided in the pre-tightening groove, which is equivalent to providing a reinforced protection for the part on the inner side of the spacer ring used to provide pre-tightening force, thereby avoiding permanent deformation under extreme conditions. After the environment improves, it is beneficial for the lens to return to normal, thereby further improving the overall structural stability of the lens, and at the same time making the stiffness of the spacer ring variable. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of an imaging lens (with a blocking protrusion) according to an embodiment of the present invention, showing an axonometric cross-sectional view (left) and a front view cross-sectional view (right);

[0026] Figure 2 A schematic cross-sectional view of an imaging lens according to an embodiment of the present invention (with a blocking protrusion and a spacer not in contact with the lens barrel) from a front viewing angle is shown;

[0027] Figure 3 Schematically showing cross-sectional views of imaging lenses according to two embodiments of the present invention (having a blocking protrusion and having an abutting protrusion) from a front viewing angle;

[0028] Figure 4 Schematic diagram of an enlarged cross-sectional view from a front viewing angle of an imaging lens (having a blocking protrusion, with the light shielding structure and the spacer being an integrated structure) according to an embodiment of the present invention;

[0029] Figure 5 Schematic diagram of a front view cross-sectional view (left) and a magnified cross-sectional view (right) of an imaging lens (with a preload groove) according to an embodiment of the present invention;

[0030] Figure 6 A schematic cross-sectional view of an imaging lens according to an embodiment of the present invention (having a preload groove and a spacer ring that does not contact the lens barrel) from a front viewing angle is shown;

[0031] Figure 7 Schematic diagram of an enlarged cross-sectional view of an imaging lens according to an embodiment of the present invention (having a preload groove, and the light shielding structure and the spacer being an integrated structure) from a main viewing angle;

[0032] Figure 8 Schematic diagram of a front view cross-sectional view (left) and a magnified cross-sectional view (right) of an imaging lens (with a reinforcement protrusion) according to an embodiment of the present invention;

[0033] Figure 9 A schematic diagram showing a front view cross-sectional view (left) and an enlarged cross-sectional view (right) of an imaging lens according to an embodiment of the present invention (having a reinforcement protrusion and with the spacer not in contact with the lens barrel);

[0034] Figure 10 A schematic diagram showing an enlarged cross-sectional view of an imaging lens according to an embodiment of the present invention (having a reinforcing protrusion, and the light shielding structure and the spacer being an integrated structure) from a main viewing angle;

[0035] Figure 11 It is an axonometric cross-sectional view of an imaging lens in the prior art. DETAILED DESCRIPTION

[0036] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0037] When describing the embodiments of the present invention, the orientation or positional relationship expressed by the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or positional relationship shown in the relevant drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0038] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The embodiments cannot be described one by one here, but the embodiments of the present invention are not limited to the following embodiments.

[0039] See also Figure 1 The imaging lens of the present invention comprises a lens barrel 1 and an optical system 2 disposed in the lens barrel 1. The optical system 2 should at least include a first lens 21 and a second lens 22 ("first" and "second" do not specifically refer to being located at the front end of the lens) arranged in sequence along the optical axis from the object side to the image side. The outer edges of the two lenses are both supported on the inner wall of the lens barrel 1 and are coaxially arranged with the lens barrel 1. A spacer 23 is provided between the first lens 21 and the second lens 22. According to the concept of the present invention, the object side (i.e., the image side) of the spacer 23 is Figure 1 An annular blocking protrusion 231 extending axially substantially toward the object side is provided on the outer edge of the first lens 21 (upper center side). The outer diameter surface of the first lens 21 abuts against the inner annular surface of the blocking protrusion 231, effectively positioning the first lens 21 within a circular groove formed on the inner side of the blocking protrusion 231. In this way, the outer rotational surface of the first lens 21 provides a reliable support for the inner rotational surface of the blocking protrusion 231, allowing the contact formed by the two supporting surfaces to effectively resist the overturning torque exerted on the spacer 23 by the diameter difference between adjacent lenses, thereby stabilizing the overall structure of the lens. Of course, in other embodiments, the optical system 2 may further include additional optical elements, such as lenses, spacers, and light-shielding elements, and may also be configured in accordance with this concept. Furthermore, the spacers of the present invention may also be applied to trimmed lenses.

[0040] like Figure 1As shown in the right side view, in the present invention, the outer edge of the spacer 23 is provided with a supporting tapered surface 234, which forms a truncated cone with the top of the cone facing upward, and the angle θ1 between the support tapered surface 234 and the optical axis is an acute angle. Correspondingly, the inner wall of the lens barrel 1 at the corresponding gear position near the spacer 23 should also be a tapered surface, thereby forming a tapered inner wall, which can cooperate with the supporting tapered surface 234. In this way, under a large axial force, the tapered inner wall between the lens barrel 1 and the spacer 23 and the supporting tapered surface 234 form a support, thereby sharing the support pressure for the part inside the spacer 23 used for compression. It can also apply a large radial force to the lens barrel 1, reducing the radial force between the lens and the lens barrel 1, thereby further releasing the large axial internal force of the lens caused by the different material expansion coefficients. In addition, the height of the blocking protrusion 231 of the present invention is more than one-fifth of the axial width of the outer (rotational) surface of the first lens 21, so that it can adapt to almost all possible axial extension distances of the lens barrel 1 and ensure that the blocking protrusion 231 resists the effect of the overturning moment. Since optical elements are generally manufactured using the injection molding process, it may be difficult to form relatively standard cylindrical surfaces on the outer side of the first lens 21 and the inner side of the blocking protrusion 231 due to process reasons. However, the draft angle (i.e., the cone angle relative to the optical axis) during molding of the two should also be controlled within the range of -5° to +5°, so that the two rotating surfaces are basically cylindrical surfaces, and the contact area between the two surfaces forms a cylindrical hinge, ensuring the connection accuracy between the spacer 23 and the first lens 21 and the guiding accuracy of the two along the optical axis. Of course, if other processes are used, the two rotating surfaces should be formed into the above-mentioned cylindrical hinge connection form as much as possible. At the same time, continue to refer to Figure 1 Right side view, in the present invention, the inner non-supporting portion 23a of the image side of the spacer 23 (i.e., the portion that does not contact the optical element on its image side) is a cone with the top of the cone facing upward, that is, the angle θ2 between this portion and the object side supporting surface of the spacer 23 (the upper end surface in the figure) is an acute angle, so that the spacer 23 can also meet certain light shielding requirements, and the portion on the inner side of the spacer 23 used to press the first lens 21 has better mechanical properties, and can also make this portion have a certain degree of elasticity.

[0041] In such Figure 1In the embodiment shown, the supporting conical surface 234 on the outside of the spacer 23 is parallel to the inner wall of the conical surface at the corresponding gear position of the lens barrel 1, or the angle difference is not greater than 2°. In this way, when the force along the optical axis causes the two conical surfaces to close (i.e., abut), the part on the inner side of the spacer 23 that plays a pressing role and the supporting conical surface 234 can jointly share the pressure transmitted to the spacer 23 from the image side, and push the lens barrel 1 radially outward, reducing the possible interference between the lens and the lens barrel 1, thereby effectively realizing the above-mentioned function of releasing the axial internal force of the lens. In this way, the outer side of the spacer 23 is divided into a cylindrical rotating surface (lower side) and a conical surface (upper side). The outer cylindrical rotating surface of the spacer 23 in this embodiment bears on the inner wall of the lens barrel 1, so that in extreme cases, when subjected to radial impact relative to the optical axis direction of the lens, its structural stability is relatively strong. Of course, it can also be as Figure 2 As shown, the cone angle of the supporting tapered surface 234 is made smaller than or equal to the inner wall of the lens barrel 1. This is mainly to prevent the spacer 23 from contacting the lens barrel 1. That is, the contact restriction between the outer edge of the spacer 23 and the inner wall of the lens barrel 1 is eliminated, so that a certain gap is formed between the two, thereby facilitating assembly and manufacturing. In the following description of other embodiments, the above common features are not repeated.

[0042] See also Figure 3 Left side view, according to one embodiment of the present invention, the image side of the first lens 21 is provided with an annular first abutting protrusion 211, the first abutting protrusion 211 is opposite to the object side supporting end face of the first lens 21, and abuts against the object side (also the end face for supporting) of the spacer 23 in the assembled state. Alternatively, see Figure 3 In the right side view, the object side of the spacer 23 is provided with an annular second abutting protrusion 235, and the second abutting protrusion 235 abuts against the image side of the first lens 21 in the assembled state. In these two types of abutting protrusion settings, the shape of the abutting protrusion is annular, that is, an additional ring band is formed on the first lens 21 or the spacer 23. In fact, no matter whether the abutting protrusion is provided on the first lens 21 or the spacer 23, the concept and function are similar, both of which are to make the axial force transmitted between the first lens 21 and the spacer 23 as straight as possible, so as to avoid bending moment between the two or reduce bending moment between the two and cause poor imaging effect. In the present invention, the heights of the above two abutting protrusions relative to their respective base planes (the image side bearing surface of the first lens 21 or the object side bearing surface of the spacer 23) are both above 5 microns to achieve their effective functions. The present invention also includes a light-shielding structure, thereby realizing the light blocking function in the lens barrel 1. As Figure 3 As shown in the embodiment, the light shielding structure is an annular light shielding sheet 241 located between the spacer 23 and the second lens 22. Figure 4As shown, the shading structure is an annular flat plate-shaped shading protrusion 242 extending from the image side of the spacer 23. This approach can also be understood as the shading sheet and the spacer 23 being integrally formed to form a combined component.

[0043] See also Figure 5 According to one embodiment of the present invention, a preload groove 232 is provided on the object side of the spacer 23. This groove is composed of an inner groove wall 232a and an outer groove wall 232b. The inner groove wall 232a is a conical surface with the apex facing upward, while the outer groove wall 232b is a cylindrical surface. The inner groove wall 232a and the outer groove wall 232b form an acute angle. Thus, the arrangement of the preload groove 232, combined with the inner conical surface on the image side of the spacer 23, weakens the rigidity of the inner side of the spacer 23 (primarily the area to the left of the preload groove 232). In other words, the inner portion of the spacer 23 has a certain degree of elasticity, allowing for large axial displacement. Because the lens barrel 1 may experience axial contraction in high-humidity environments, this highly elastic design helps reduce the axial force on the optical system 2 under extreme conditions. Furthermore, the lens barrel 1 may also experience axial expansion in high-temperature environments. This elastic design allows the spacer 23 to maintain a certain amount of precompression during assembly, thereby helping the lens maintain a certain axial preload even when the temperature fluctuates significantly. It can be seen that the method of providing the pre-tightening groove 232 on the spacer 23 can make the inner side of the spacer 23 have strong elasticity, so that the pre-tightening force and large deformation along the optical axis can provide more reliable axial compression in high temperature and high humidity environments. Of course, the elasticity factor is also combined with the material of the spacer 23. For example, the material of the spacer 23 is generally copper alloy, resin or plastic, which can make the spacer 23 have good elasticity. Figure 5 In the embodiment shown, the outer side (cylindrical rotation surface) of the spacer 23 bears against the inner wall of the lens barrel 1, so that the stability of the structure is stronger when it is subjected to a large radial impact. Figure 6 As shown, a certain gap is formed between the outer side of the spacer 23 and the inner wall of the lens barrel 1, thereby forming a structure that is easy to assemble and manufacture. In addition, Figure 5 and Figure 6 In the embodiment shown, the light shielding structure is an annular light shielding sheet 241 located between the spacer 23 and the second lens 22. Of course, it can also be as Figure 7 As shown, the shading structure is an annular flat plate-shaped shading protrusion 242 extending from the image side of the spacer 23. Similarly, this approach can also be understood as the shading sheet and the spacer 23 being integrally formed to form a combined component.

[0044] See also Figure 8According to one embodiment of the present invention, the bottom of the pre-tightening groove 232 is provided with an annular reinforcing protrusion 233 extending axially toward the object side. The inner side wall 233a of the reinforcing protrusion 233 is a cylinder, and the object side wall 233b (i.e., the upper side wall in the figure) is an annular plane. In this way, the reinforcing protrusion 233 provides a reinforcing effect for the pre-tightening groove 232, and provides a protection for the inner part of the spacer 23 under the axial limit compression state of the spacer 23, thereby avoiding permanent deformation of the inner side of the spacer 23 under extreme conditions, thereby facilitating the lens to return to normal after the environment improves, that is, further improving the stability of the structure. In combination with the above description of the supporting cone 234, it can be seen that, when necessary, the reinforcing protrusion 233 can also play a role in sharing the pressure transmitted to the spacer 23 from the image side to a certain extent. In such a case Figure 8 In the embodiment shown, the outer side (cylindrical rotation surface) of the spacer 23 bears against the inner wall of the lens barrel 1, so that the stability of the structure is stronger when it is subjected to a large radial impact. Figure 9 As shown, a certain gap is formed between the outer side of the spacer 23 and the inner wall of the lens barrel 1, thereby forming a structure that is easy to assemble and manufacture. In addition, Figure 8 and Figure 9 In the embodiment shown in FIG, the light shielding structure is an annular light shielding sheet 241 located between the spacer 23 and the second lens 22. Of course, it can also be as shown in FIG. Figure 10 As shown, the shading structure is an annular flat plate-shaped shading protrusion 242 extending from the image side of the spacer 23. In this embodiment, the shading sheet and the spacer 23 are integrally formed to form a combined component.

[0045] According to the above-mentioned embodiment of the present invention, for the spacer 23 between two lenses with a large diameter difference, the inner rotation surface of its blocking protrusion 231 and the outer rotation surface of the first lens 21 can form a reliable bearing relationship, which can effectively resist the overturning moment applied by the lens to the spacer 23. The bearing conical surface 234 on the outer side of the spacer 23 can be matched with the conical surface provided on the wall of the corresponding gear of the lens barrel 1. When the two are supported under large axial force, the inner part of the spacer 23 that plays a compressive role can be protected. It can also apply a large radial force to the lens barrel 1, reducing the radial force between the lens and the lens barrel 1, and further relieving the large axial internal force of the lens caused by the different material expansion coefficients. In some embodiments, the provision of abutment protrusions can ensure that the axial force transmitted between the spacer 23 and the first lens 21 is as straight as possible, thereby avoiding or reducing the generation of bending moments that affect the imaging effect of the lens. In some embodiments, the provision of a preload groove 232 creates a highly elastic compression area on the inner side of the spacer 23, thereby providing a preload force along the optical axis and a large deformation range, thereby providing reliable axial compression in high-temperature and high-humidity environments. Some embodiments also include a reinforcing protrusion 233 within the preload groove 232 to protect the compression area on the inner side of the spacer 23 from permanent deformation in extreme conditions, facilitating the lens's return to normal operation after the environment improves. Furthermore, the above-described embodiments are not the only ones of the present invention; where appropriate or required, the various embodiments may be combined to form new implementations.

[0046] The above description is merely one embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. An imaging lens, comprising a lens barrel (1) and an optical system (2) arranged in the lens barrel (1), wherein the optical system (2) comprises at least a first lens (21) and a second lens (22) arranged in sequence from the object side to the image side along the optical axis, wherein the outer edges of the first lens (21) and the second lens (22) bear against the inner wall of the lens barrel (1), and a spacer (23) is provided between the first lens (21) and the second lens (22), wherein: The outer edge of the spacer (23) on the object side is provided with an annular blocking protrusion (231) extending axially toward the object side, and the outer diameter surface of the first lens (21) and the inner annular surface of the blocking protrusion (231) abut against each other; The outer edge of the spacer (23) is divided into a supporting cone surface (234) and a cylindrical rotation surface arranged in sequence from the object side to the image side of the optical axis, and the angle θ1 between the supporting cone surface (234) and the optical axis is an acute angle; the lens barrel (1) has a conical inner wall that can cooperate with the supporting cone surface (234) near the spacer (23); there is a gap between the outer edge of the spacer (23) and the inner wall of the lens barrel (1) or the spacer rests on the inner wall of the lens barrel (1); the supporting cone surface (234) is parallel to the inner wall of the cone surface or the angle difference between the supporting cone surface and the inner wall is not greater than 2°; The inner non-supporting portion (23a) on the image side of the spacer (23) is a conical surface, and the angle θ2 between the inner non-supporting portion (23a) and the object side supporting surface of the spacer (23) is an acute angle.

2. The imaging lens according to claim 1, wherein: An annular first abutting protrusion (211) is provided on the image side of the first lens (21), and the first abutting protrusion (211) abuts against the object side of the spacer (23) in an assembled state.

3. The imaging lens according to claim 1, wherein: An annular second abutting protrusion (235) is provided on the object side of the spacer (23), and the second abutting protrusion (235) abuts against the image side of the first lens (21) in an assembled state.

4. The imaging lens according to claim 2 or 3, wherein: The height of the abutting protrusion is above 5 microns.

5. The imaging lens according to claim 1, wherein: The height of the blocking protrusion (231) is greater than one fifth of the axial width of the outer side surface of the first lens (21).

6. The imaging lens according to claim 1, wherein: It also includes a light shielding structure, which is a light shielding plate (241) located between the spacer (23) and the second lens (22) or a ring-shaped light shielding protrusion (242) extending from the image side of the spacer (23).

Images