EP-3933473-B1 - OPTICAL LENS, CAMERA MODULE AND MANUFACTURING METHOD THEREOF

EP3933473B1EP 3933473 B1EP3933473 B1EP 3933473B1EP-3933473-B1

Inventors

CHEN, Liefeng
MEI, ZHEWEN
TANAKA, TAKEHIKO
LIU, LIN

Dates

Publication Date: 20260506
Application Date: 20200311

Claims (13)

An optical lens, comprising: a lens component (2001), preferably a split lens component, including at least one first lens and a lens barrel portion holding the at least one first lens therein, wherein an outer side portion of the lens barrel portion has a first fastener (2002) arranged in a circumferential direction; a lens driving component, including a drive portion and a driving portion carrier (3003), wherein the driving portion drives the lens component (2001), and an inner side portion of the driving portion carrier (3003) has a second fastener arranged in a circumferential direction; wherein the first fastener (2002) and the second fastener are engaged to couple the lens component (2001) and the lens driving component, and the first fastener (2002) has an inclined portion (2003) which is located on an upper surface or a lower surface of the first fastener (2002) in an axial direction of the lens component, and the inclined portion (2003) is configured obliquely in the circumferential direction, wherein the first fastener (2002) has a lower end configured to, during the assembly process, enter and engage the second female fastener through rotation such that the first and second fasteners are clamped together and tightly combined without any gap at the clamping point; and whereby a glue material is located between the first fastener (2002) and the second fastener to bond the lens component (2001) and the lens driving component together.
The optical lens according to claim 1, wherein a maximum dimension of the inclined portion (2003) in the optical axial direction is the same as a maximum dimension of the other fastener in the optical axial direction.
The optical lens according to claim 1, wherein the glue material is a light curing, thermal curing, moisture curing, anaerobic curing or oxidative curing glue material.
The optical lens according to claim 1, wherein the first fastener (2002) is a male fastener, and the second fastener is a female fastener.
The optical lens according to claim 1, wherein at least one of the first fastener (5001) and the second fastener includes a boss (5003) to prevent the first fastener (5002) from releasing from the second fastener.
The optical lens according to claim 1, wherein the first fastener (4003, 4004) and the second fastener (4006, 4005) are configured in two or more layers along the optical axial direction.
The optical lens according to claim 1, wherein the first fastener (2002) and the second fastener are evenly distributed along the optical axial direction.
A method of manufacturing an optical lens, comprising: arranging a first fastener (2002) along a circumferential direction of an outer side portion of a lens barrel portion of a lens component (2001), preferably a split lens component; arranging a second fastener along a circumferential direction of an inner side portion of a driving portion carrier (3003) of a lens driving component; configuring an inclined portion (2003) on the first fastener (2002), wherein the inclined portion (2003) is located on an upper surface or a lower surface of the first fastener (2002) in an axial direction of the lens component, and the inclined portion (2003) is configured obliquely in the circumferential direction, wherein the first fastener (2002) having a lower end entering and engaging the second female fastener through rotation, and wherein during the assembly process, by rotation of the first fastener, the first and second fasteners are clamped together and tightly combined without any gap at the clamping point; and applying a glue material between the first fastener (2002) and the second fastener to bond the lens component (2001) and the lens driving component together, and preferably the glue material is a light curing, thermal curing, moisture curing, anaerobic curing or oxidative curing glue material.
The method of manufacturing an optical lens according to claim 8, wherein a maximum dimension of the inclined portion (2003) in the optical axial direction is the same as a maximum dimension of the other fastener in the optical axial direction.
The method of manufacturing an optical lens according to claim 8, wherein the first fastener (2002) is a male fastener, and the second fastener is a female fastener.
The method of manufacturing an optical lens according to claim 8, wherein at least one of the first fastener (2002) and the second fastener includes a boss to prevent the first fastener (2002) from releasing from the second fastener.
The method of manufacturing an optical lens according to claim 8, wherein the first fastener (2002) and the second fastener are configured in two or more layers along the optical axial direction.
The method of manufacturing an optical lens according to claim 8, wherein the first fastener (2002) and the second fastener are evenly distributed along the optical axial direction.

Description

FIELD OF THE INVENTION This application relates to field of optical lenses, and particularly to an optical lens, a camera module and a manufacturing method thereof. BACKGROUND OF THE INVENTION With the continuous development and progress of science and technology, mobile electronic equipment have become more and more popular, and the related technologies of imageable optical devices used in mobile electronic equipment to help users obtain images (such as videos or images) have been rapidly developed and advanced, and have been widely used in many fields such as medical treatment, security, industrial production, etc. In order to meet the increasing demand of consumers for taking pictures, auto-focusing camera modules are widely used in digital products, such as smart phones, tablet computers, surveillance and other terminal devices, and are showing a trend of rapid development. Nowadays, digital products are developing towards miniaturization and high-performance. Correspondingly, higher and higher requirements are put forward for the volume and performance of auto-focusing camera modules. Factors affecting the resolution of imageable optical devices of a given optical design include the quality of optical imaging lenses and the manufacturing errors in a module packaging process. Specifically, in the manufacturing process of the optical imaging lenses, the factors affecting the resolution of the lens come from the errors of each element and its assembly, the error of the thickness of a lens spacer element, the error of the assembly and coordination of each lens, and the change of the refractive index of a lens material. In the art, a motor is usually used to realize autofocus of an optical lens. A voice coil motor is one of the mechanisms used to provide automatic focusing of the optical lens. In a camera module with a voice coil motor, the optical lens is first installed in a lens barrel, and the lens barrel is arranged in the voice coil motor carrier through a thread or fastener connection method. However, the thread or fastener connection method will adversely affect the volume or performance of the camera module. When the lens barrel and the motor carrier are connected in the thread method, a thread portion needs to be machined in the motor carrier and on a side wall of the lens barrel. The thread portion will make the corresponding drive motor larger, resulting in a relatively larger volume of the camera module. In addition, when the lens barrel is screwed into the motor for engagement through the thread portion, due to the action of torsion, the engagement between the thread portion on the lens barrel and the thread portion on the carrier will generate debris, and this debris will cause particulate pollution to the camera module, which makes an imaging dirty. The fastener connection method can reduce the generation of the debris to a certain extent. The conventional fastener connection is to first connect a lens component and the motor through a fastener, then apply a glue material at the fastener, and finally cure the glue material by a method corresponding to the glue material, so that the lens and the drive motor are firmly engaging, in which the method of curing the glue material includes UV exposure or baking. Since the position of the fastener is fixed, a height fixing process in a common motor lens locking process can be omitted. However, as current lens specifications continue to increase, from 20M, 40M, and 48M to 64M and even higher pixel numbers, it is necessary to design higher-pixel lenses in a smaller space. Such lenses have very high optical sensitivity. Therefore, the requirements for eccentricity and tilt generated in the manufacturing process of the optical lens are very strict. In the current fastener connection method, in order to enable a female fastener of the fastener on the motor carrier to engage with a male fastener of the fastener on the lens barrel, there is a gap of at least 0.1 mm between the female fastener of the fastener and the male fastener of the fastener. Therefore, the gap cannot be effectively eliminated at present. When the glue material is cured, the glue material will shrink. The force generated by shrinkage will pull the male fastener of the fastener to move in any possible direction, and drive lens position to move (mainly upward). Because the amount of the glue material applied at each fastener is inconsistent, and the direction of shrinkage of the glue material is also inconsistent, the lens deviates from an optical axis and causes a certain eccentricity and tilt. As a result, the Active Alignment process cannot be used to compensate for all tilts, which seriously affects the assembly yield of the camera module. In addition, as mentioned above, because there are many factors that affect the resolution of the lens, which exist in multiple components, the control of each factor has the limit of manufacturing accuracy. If only the accuracy of each component i