Patent Description:
In a lens assembly of a mobile terminal such as a digital camera, a camera device, and a mobile phone, interference is present between a lens barrel and a lens assembled within. However, excessive interference between the lens barrel and the lens may deform the lens, degrading a resolving power of the lens assembly and affecting the quality of photographing. A direction of studies in the industry is how to design making the interference between the lens and the lens barrel within an expected range without causing deformation on the lens while ensuring the resolving power of the lens assembly and the quality of photographing.

Document <CIT> describes an image pickup lens and a reliable image pickup device, wherein the lens comprises a step portion and is arranged in a lens frame.

Document <CIT> describes a lens device, in which a lens is fixed to a lens holder by using a structure that does not require a screw portion.

Document <CIT> describes a camera lens. The camera lens comprises a projection and a groove as well as the lens frame. Document <CIT> describes a lens fixing structure that fixes a lens in a holding hole of a lens holding frame. The lens has three projections projecting from an outer peripheral surface in a radial direction; an inner circumferential wall part of the holding hole has three engagement surfaces gradually decreasing a distance from a center axis line as viewed from a rotating direction; in each engagement surface, a position most distant from the center axis line is set to be larger than the size dimension of the projection from a lens optical axis LA; in each engagement surface, a position closest from the center axis line is set to be smaller than the size dimension of the projection from a lens optical axis and larger than the size dimension of the outer peripheral surface from the a lens optical axis; and each projection is made to be engaged with each corresponding engagement surface. Document <CIT> describes a bonding and fixing structure of a lens including a lens having a projection part to which an adhesive can be applied on a peripheral part, a lens frame having a first fixing wall part and a second fixing wall part facing mutually across the projection part, and an adhesive setting part for fixing the lens to the lens frame, by filling with the adhesive portions between the first fixing wall part and the projection part, and between the second fixing wall part and the projection part and setting the adhesive.

Embodiments of this application provide a lens assembly, a camera module, and a terminal, to resolve problems of lens deformation and degraded imaging quality caused by large assembly interference between a lens barrel and a lens. The present invention is defined by the attached set of claims.

According to a first aspect, this application provides a lens assembly as defined in claim <NUM>, including a lens barrel and a lens. The lens barrel is hollow and includes an interior surface. Specifically, the lens barrel is in a tubular shape with openings at both ends. An accommodation space formed by the surrounding interior surface is used to install the lens. A central axis of the lens barrel is an optical axis of the lens assembly. The lens is disposed inside the lens barrel, and the lens includes a side surface in interference fit with the interior surface. Specifically, a central area of the lens is a light-transmitting area, an edge area of the lens surrounds the central area, and the edge area is used to assemble the lens into the lens barrel. The side surface is an exterior surface of the edge area that fits the lens barrel, and the side surface is in contact and interference fit with the interior surface of the lens barrel. The interior surface of the lens barrel has a hollow area. The hollow area may be a groove of any shape, such as a square groove, a curved groove, a semicircular groove, a triangular groove, or an irregular shape. The hollow area is a concave area formed in an inner wall of the lens barrel by removing materials. The hollow area may alternatively be an area formed by a plurality of fine-stripe channels or slits. The side surface includes a micro-convex structure, where the micro-convex structure in the side surface of the lens is an irregular surface protrusion structure that appears on the lens during processing. For example, the side surface of the lens should be theoretically designed as a cylindrical surface. However, during manufacturing, the micro-convex structure is inevitably formed on the side surface of the lens because of reasons such as mould structure and processing art. In this application, a fit quantity between the micro-convex structure and the hollow area is changed through relative rotation of the lens and the lens barrel, to adjust assembly interference between the lens barrel and the lens. After the lens is installed into the lens barrel, the side surface is in interference fit with the interior surface. Relatively large interference may cause deformation of the lens and affect imaging quality. In this application, at least a portion of the micro-convex structure is moved into the hollow area by rotating the lens. That is, the hollow area absorbs some interference between the micro-convex structure and the interior surface. When the micro-convex structure is completely accommodated in the hollow area, interference between the lens and the lens barrel is minimum. In this application, an amount of deformation of the lens is controlled by reducing the interference between the lens and the lens barrel, thereby ensuring the imaging quality.

In an implementation, the hollow area is filled with a cushioning material, and the lens is in contact with the cushioning material in the hollow area, to absorb the assembly interference between the lens and the interior surface of the lens barrel. The cushioning material may be a material characterized by elastic cushioning, such as glue, foam, and silicone.

There are a plurality of hollow areas. The plurality of hollow areas are separated from each other, arranged along a peripheral of the lens, and directly facing the side surface of the lens. The arranging two or more than two hollow areas can improve efficiency of interference between the lens and a camera, so that the micro-convex structure can quickly fit a hollow area during rotation of the lens. Certainly, a quantity of micro-convex structures on the side surface of the lens is not limited to only one. There may be two or more micro-convex structures. In this way, two or more micro-convex structures fit two or more hollow areas, which can adjust the interference between the lens and the lens barrel to a greater extent.

In an implementation, the hollow area includes a first hollow area and a second hollow area, where the first hollow area is one or more first hollow structures, and the second hollow area is one or more second hollow structures. The lens includes a top lens, a bottom lens, and at least one middle lens stacking between the top lens and the bottom lens, where the top lens and the bottom lens are both in interference fit with the lens barrel, and the at least one middle lens is in clearance fit with the lens barrel. The at least one first hollow structure fits a micro-convex structure of the top lens, and the at least one second hollow structure fits a micro-convex structure of the bottom lens.

In this implementation, a multi-layer lens structure is determined. After positions of the top lens and the bottom lens are determined, a position of the middle lens is fixed. Therefore, clearance interference between the middle lens and the lens barrel can ensure that the middle lens is not deformed due to the assembly interference. The top lens may be a one-layer or two-layer lens structure. The bottom lens may be also a one-layer or two-layer lens structure.

In an implementation, a glue chute is arranged in the lens barrel, where the glue chute extends from an end face of the lens barrel to the hollow area, and the glue chute is configured to fill glue into the hollow area after the lens is assembled into the lens barrel. Filling glue in the glue chute can improve a strength and overall rigidity of the lens assembly, avoiding displacement or deformation of the lens.

In an implementation, the glue chute includes a first glue chute and a second glue chute, where the first glue chute extends from a top end face of the lens barrel to the hollow area that fits the top lens, and the second glue chute extends from a bottom end face of the lens barrel to the hollow area that fits the bottom lens. In this implementation, two glue chutes are provided to dispense glue for the top lens and the bottom lens so as to fill glue in the hollow area. This makes glue filling easy without affecting the middle lens.

In an implementation, a connection channel is further disposed on the inner wall of the lens barrel. The plurality of first hollow structures are connected to each other through the connection channel, and the second hollow structures are connected to each other through the connection channel.

The hollow area includes a groove or a plurality of slits that are adjacent to each other and arranged in parallel.

In an implementation, the plurality of slits are arranged in parallel in an axial direction of the lens barrel, and are correspondingly arranged along a peripheral of the top lens or the bottom lens.

In other words, a hollow area at one position may be a structure including a complete groove or a structure including a plurality of slits.

According to a second aspect, this application further provides a camera module, including a circuit board, a chip, a light filter, and the lens assembly according to any one of the foregoing implementations, where the chip is disposed on a top surface of the circuit board, the light filter is fixed on the bottom surface of the lens barrel of the lens assembly, with the bottom surface of the lens barrel connected to the top surface of the circuit board, and the chip is disposed opposite to the lens.

According to a third aspect, this application further provides a terminal, including the camera module.

To describe the technical solutions in the embodiments of the present invention or in the background more clearly, the following briefly describes the accompanying drawings required for describing the embodiments of the present invention or the background.

This application provides a lens assembly, applied to a camera module of a terminal product. The terminal may be a mobile phone, a tablet, a video camera, or the like.

Referring to <FIG>, <FIG>, and <FIG>, a lens assembly includes a lens barrel <NUM> and a lens <NUM>. The lens barrel <NUM> is hollow and includes an interior surface <NUM>. Specifically, the lens barrel <NUM> is in a tubular shape with openings at both ends. An accommodation space formed by the surrounding interior surface <NUM> is used to install the lens <NUM>. The lens barrel <NUM> includes a first end <NUM> and a second end <NUM>. A central axis of the lens barrel <NUM> is an optical axis of the lens assembly. The lens <NUM> is disposed inside the lens barrel <NUM>, and the lens <NUM> includes a side surface <NUM> in interference fit with the interior surface <NUM>. Specifically, a central area of the lens <NUM> is a light-transmitting area, an edge area of the lens <NUM> surrounds the central area, and the edge area is used to assemble the lens <NUM> into the lens barrel <NUM>. The side surface <NUM> is an exterior surface of the edge area that fits the lens barrel <NUM>, and the side surface <NUM> is in contact and interference fit with the interior surface <NUM> of the lens barrel <NUM>. Interference fit described in this embodiment of this application refers to an interference fit relationship between the lens <NUM> and the lens barrel <NUM>. Specifically, when the lens <NUM> is assembled into the lens barrel <NUM> under action of an external force, the side surface <NUM> of the lens <NUM> presses the interior surface <NUM> of the lens barrel <NUM>. A pressing force fixes the lens <NUM> into the lens barrel <NUM>. The pressing also makes the lens <NUM> prone to be deformed. Such an installation relationship is referred to as interference fit.

The interior surface <NUM> of the lens barrel <NUM> has a hollow area <NUM>. The hollow area <NUM> may be a groove of any shape, such as a square groove, a curved groove, a semicircular groove, a triangular groove, or an irregular shape. The hollow area <NUM> may alternatively be an area formed by a plurality of fine-stripe channels or slits. The hollow area <NUM> is a concave area formed in an inner wall of the lens barrel <NUM> by removing materials.

Referring to <FIG> and <FIG>, the side surface <NUM> of the lens <NUM> includes a micro-convex structure <NUM>, where the micro-convex structure <NUM> in the side surface <NUM> of the lens <NUM> is an irregular surface protrusion structure that appears on the lens <NUM> during processing. For example, the side surface <NUM> of the lens <NUM> should be theoretically designed as a smooth cylindrical surface. However, during manufacturing, the micro-convex structure <NUM> is inevitably formed on the side surface <NUM> of the lens <NUM> because of reasons such as mould structure and processing art. The micro-convex structure <NUM> may be of any shape. In the embodiment shown in <FIG>, the lens <NUM> includes micro-convex structures <NUM> of four different shapes.

In this application, the hollow area <NUM> is configured in the lens barrel <NUM>. When the lens <NUM> is installed into the lens barrel <NUM>, the lens <NUM> can be rotated so that the micro-convex structure <NUM> of the lens <NUM> falls in the hollow area <NUM>. This changes a fit quantity between the micro-convex structure <NUM> and the lens barrel, adjusting assembly interference between the lens barrel <NUM> and the lens <NUM>, that is, adjusting the pressing force between the lens barrel <NUM> and the lens <NUM>.

After the lens <NUM> is installed into the lens barrel <NUM>, the side surface <NUM> is in interference fit with the interior surface <NUM>, causing deformation of the lens <NUM> and affecting imaging quality. In the embodiment shown in <FIG>, the micro-convex structure <NUM> and the hollow area <NUM> do not intersect, and are separated from each other. In this case, interference between the micro-convex structure <NUM> and the interior surface <NUM> of the lens barrel <NUM> is relatively large, making the lens <NUM> prone to deformation. As shown in <FIG>, the lens <NUM> is rotated so that at least a portion of the micro-convex structure <NUM> is moved into the hollow area <NUM>. That is, the hollow area <NUM> absorbs some interference between the micro-convex structure <NUM> and the interior surface <NUM>, to reduce the mutual pressing force between the lens barrel <NUM> and the lens <NUM>. When the micro-convex structure <NUM> is completely accommodated in the hollow area <NUM>, the interference between the lens <NUM> and the lens barrel <NUM> is minimum. In this application, an amount of deformation of the lens <NUM> is controlled by reducing the interference between the lens <NUM> and the lens barrel <NUM>, thereby ensuring the imaging quality.

Referring to <FIG>, in an implementation, the hollow area <NUM> is filled with a cushioning material <NUM>, and the cushioning material <NUM> is used to contact the lens <NUM> to absorb the assembly interference between the lens <NUM> and the interior surface <NUM> of the lens barrel <NUM>. The cushioning material <NUM> may be a material characterized by elastic cushioning, such as glue, foam, and silicone.

Referring to <FIG> and <FIG>, in an implementation, there are a plurality of hollow areas <NUM>. The plurality of hollow areas <NUM> are separated from each other, arranged along a peripheral of the lens <NUM>, and directly facing the side surface <NUM> of the lens <NUM>. The arranging two or more than two hollow areas <NUM> can improve efficiency of interference between the lens <NUM> and a camera, so that the micro-convex structure <NUM> can quickly fit a hollow area <NUM> during rotation of the lens <NUM>. Certainly, a quantity of micro-convex structures <NUM> on the side surface <NUM> of the lens <NUM> is not limited to only one. There may be two or more micro-convex structures <NUM>. In this way, two or more micro-convex structures <NUM> fit two or more hollow areas <NUM>, which can adjust the interference between the lens <NUM> and the lens barrel <NUM> to a greater extent.

In an implementation, the hollow area <NUM> includes a first hollow area and a second hollow area, where the first hollow area is one or more first hollow structures, and the second hollow area is one or more second hollow structures.

In an implementation, the lens <NUM> includes a top lens, a bottom lens, and at least one middle lens stacking between the top lens and the bottom lens. The at least one first hollow structure fits a micro-convex structure of the top lens, the top lens and the bottom lens are both in interference fit with the lens barrel, and the at least one second hollow structure fits a micro-convex structure of the bottom lens.

As shown in <FIG>, the lens <NUM> includes a first lens <NUM>, a second lens <NUM>, a third lens <NUM>, a fourth lens <NUM>, a fifth lens <NUM>, and a sixth lens <NUM> that are sequentially stacked. The first lens <NUM> and the second lens <NUM> are top lenses, the third lens <NUM>, the fourth lens <NUM>, and the fifth lens <NUM> are middle lenses, and the sixth lens <NUM> is a bottom lens. The hollow area <NUM> is distributed along a peripheral of the top lenses and the bottom lens. The middle lens is in clearance fit with the lens barrel. In this implementation, a multi-layer lens structure is determined. After positions of the top lens and the bottom lens are determined, a position of the middle lens is fixed. Therefore, the clearance interference between the middle lens and the lens barrel <NUM> can ensure that the middle lens is not deformed due to the assembly interference. The top lens may be a one-layer or two-layer lens structure. The bottom lens may be also a one-layer or two-layer lens structure.

In an implementation, a glue chute is arranged in the lens barrel <NUM>, the glue chute extends from an end face of the lens barrel <NUM> to the hollow area <NUM>, and the glue chute is configured to fill glue into the hollow area <NUM> after the lens <NUM> is assembled into the lens barrel <NUM>. Filling glue in the glue chute can improve a strength and overall rigidity of the lens assembly, avoiding displacement or deformation of the lens <NUM>.

In an implementation, the glue chute includes a first glue chute <NUM> and a second glue chute <NUM>. The first glue chute <NUM> extends from a top end face of the lens barrel <NUM> to the hollow area <NUM> that fits the top lens (the first lens <NUM>), and the first glue chute <NUM> extends to a position in the hollow area <NUM> that fits the first lens <NUM> and the second lens <NUM>. The second glue chute <NUM> extends from a bottom end face of the lens barrel <NUM> to the hollow area <NUM> that fits the bottom lens (the sixth lens <NUM>). In this implementation, two glue chutes <NUM> and <NUM> are provided to dispense glue for the top lens and the bottom lens so as to fill glue in the hollow area <NUM>. This makes glue filling easy without affecting the middle lens.

As shown in <FIG>, in an implementation, a connection channel <NUM> is further disposed on the inner wall of the lens barrel <NUM>. The hollow area <NUM> along a peripheral of the lens <NUM> includes at least two hollow structures, and the connection channel <NUM> is used to connect the at least two hollow structures <NUM>.

The hollow area <NUM> includes a groove or a plurality of slits that are adjacent to each other and arranged in parallel. In an implementation, the hollow area <NUM> includes a plurality of slits that are arranged in parallel in an axial direction of the lens barrel <NUM>, and are correspondingly arranged along a peripheral of the top lens or the bottom lens. As shown in <FIG>, the hollow area <NUM> that is configured along a peripheral of the first lens <NUM> includes three slits arranged in parallel. In other words, a hollow area <NUM> at one position may be a structure including a complete groove or a structure including a plurality of slits.

Referring to <FIG>, this application further provides a camera module, including a circuit board <NUM>, a chip <NUM>, a light filter <NUM>, and a lens assembly. The chip <NUM> is disposed on a top surface of the circuit board <NUM>, the light filter <NUM> is fixed on a bottom surface (that is, a second end face <NUM>) of a lens barrel <NUM> of the lens assembly, with the bottom surface of the lens barrel <NUM> connected to the top surface of the circuit board <NUM>, and the chip <NUM> is disposed opposite to a lens <NUM>. A bracket <NUM> is arranged between the lens barrel <NUM> and the circuit board <NUM>. The bracket <NUM> is fixedly connected between the circuit board <NUM> and the lens barrel <NUM>. Adhesives may be used to fix the bracket <NUM> to the circuit board <NUM> and the bracket <NUM> to the lens barrel <NUM>.

Claim 1:
A lens assembly applied for a mobile phone, comprising a lens barrel (<NUM>) and a lens (<NUM>), wherein the lens barrel (<NUM>) is hollow and comprises an interior surface (<NUM>), the lens (<NUM>) is disposed inside the lens barrel (<NUM>), and the lens (<NUM>) comprises a side surface (<NUM>) in interference fit with the interior surface (<NUM>), wherein the interior surface (<NUM>) has a hollow area (<NUM>), the side surface (<NUM>) comprises a micro-convex structure (<NUM>), and the hollow area (<NUM>) fits the micro-convex structure (<NUM>),
wherein a fit quantity between the micro-convex structure (<NUM>) and the hollow area (<NUM>) is changed through relative rotation of the lens (<NUM>) and the lens barrel (<NUM>), to adjust assembly interference between the lens barrel (<NUM>) and the lens (<NUM>).