# Patent

## Title
Lens module

## Abstract

A lens module is disclosed. A lens module includes a lens barrel including a first barrel wall extended horizontally and a second barrel wall extended from the first barrel wall; a lens group including at least one lens located in the lens barrel, the lens comprising a first surface close to the first barrel wall and a second surface opposite to the first surface; and a stop clamped between the lens barrel and the lens. The first surface of the lens is provided with a first slope, an inner surface of the first barrel wall of the lens barrel is provided with a second slope abutting against first slope, and the stop creates a light hole for the lens.

## Background
FIELD OF THE DISCLOSURE
The present utility relates to a lens module, particularly to the lens module of mobile phones, digital cameras, PDAs, note books and other electronic products.
BACKGROUND
As the photographic technology and the electronic products with photographic function are developed in recent years, optical camera lens module is used widely in many kinds of products. In order to follow the current trend that the size of electronic products is smaller, the lens module shall also be smaller.
In the existing technology, the lens module comprises a lens barrel having a central axis, lenses installed in the lens barrel and a stop clamped between the lenses. The lens barrel comprises a first barrel wall extended horizontally, i.e., at right angles to the central axis and a second barrel wall extended from the first barrel wall along the central axis direction. A light hole is created on the first barrel wall for the lens. However, the light hole on the first barrel wall requires the barrel wall with a certain thickness, therefore, the wall thickness of the barrel wall is increased, and the height and weight of the entire lens module is increased. As a result, it will be more difficult to produce the lens barrel. In the existing technology, a slope is also provided on the first barrel wall at the position of the light hole; so, the difficulty of production is increased further.
For this reason, it is necessary to provide a novel lens module to overcome the shortcomings above.



BRIEF DESCRIPTION OF THE DRAWINGS
Many aspects of the embodiment can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
FIG. 1 is an illustration of a lens module in accordance with an exemplary embodiment of the present disclosure.
FIG. 2 is an illustration of a lens barrel of the lens module in FIG. 1.
FIG. 3 is an illustration of the lens group in the lens module in FIG. 1.



DETAILED DESCRIPTION
The present disclosure will be described in detail below with reference to the attached drawings and an exemplary embodiment thereof.
As shown in FIG. 1, the lens module 100 disclosed in the present embodiment comprises a lens barrel 1 having a central axis O, a lens group 2 (see FIG. 3) installed in the lens barrel 1, and a stop 3 installed between the lens barrel 1 and the lens group 2.
As shown in FIG. 2, the lens barrel 1 comprises a first barrel wall 11 extended horizontally and a second barrel wall 12 extended downward from the first barrel wall 11. A receiving space 13 is created by the first barrel wall 11 and the second barrel wall 12. The first barrel wall 11 creates a hole 111 which is connected to the receiving space 13. The inner surface of the first barrel wall 11 comprises in turn along the direction of the central axis of the lens barrel 1 as follows: a first flat surface 112 extended horizontally, a second slope 113 and a second flat surface 114 extended horizontally.
As shown in FIG. 3, the lens group 2 comprises a first lens 21 and a second lens 22 which is stacked on the first lens 21. The lens group 2 in this embodiment comprises two lenses. In other embodiments, the lens group can comprise one lens or more than two lenses. The first lens 21 comprises a first surface 211 far from the second lens 22 and a second surface 212 opposite to the first surface 211. The first lens 21 comprises a protruding central portion 213 and a peripheral portion 214 around the protruding central portion 213. The first surface 211 of the first lens 21 comprises, in turn from external to internal, as follows: a first flat surface 215 extended horizontally, a first slope 216 against the second slope 113, a second flat surface 217 extended horizontally, a third flat surface 218 which is lower than the second flat surface and a first optical surface 219. The first flat surface 215, the first slope 216, the second flat surface 217 and the third flat surface 218 are located at the peripheral portion 214 of the first lens 21. The first optical surface 219 is a circular arc surface and located on the protruding central portion 213 of the first lens 21. The included angle between the first slope 216 and the optical axis of the lens is equal to the included angle between the second slope 113 and the optical axis of the lens. The first slope 216 and the second slope 113 fit in completely with each other. A gap is created between the third flat surface 218 and the stop 3. The peripheral portion 214 of the first lens 21 is clamped between the first barrel wall 11 and the second lens 22. The optical axis of first lens 21, the optical axis of the second lens 22 and the central axis of the lens barrel 1 are aligned in one straight line.
The stop 3 is clamped between the first barrel wall 11 of the lens barrel 1 and extended horizontally and inwardly beyond the first barrel wall 11. The stop 3 comprises a light hole 31 for the protruding central portion 213 of the first lens 21. The stop 3 is a hollow ring. The aperture of the light hole 31 is smaller than the aperture of the hole 111. The central axis of the stop 3, the optical axis of the lens group 2 and the central axis of the lens barrel 1 are aligned in one straight line. The stop 3 contacts the first optical surface 218 of the first lens 21.
When assembling the lens module 100, the lens barrel 1 and the stop 3 are installed first. The stop 3 is installed in the lens barrel 11. The central axis of the stop 3 and the central axis of the lens barrel 1 are aligned in one straight line. The first lens 21 is installed under the stop 3. The first flat surface 215 of the first lens 21 is against the first flat surface of the first barrel wall 11 of the lens barrel 1. The first slope 216 of the first lens 21 is against the second slope 113 of the first barrel wall 11. The fit between the slopes ensures the concentricity between the first lens 21 and the lens barrel 1. The first lens 21 can be pressed precisely into the lens barrel 1. The stop 3 is clamped between the second flat surface 217 of the first lens 21 and the second flat surface 114 of the first barrel wall 11, thereby the stop can be fixed firmly. The first optical surface 219 of the first lens 21 is extended beyond the light hole 31 of the stop 3. The edge of the first lens 21 has press fit with the inner surface of the second barrel wall 12 of the lens barrel 1. The second lens 22 is installed under the first lens 21. The edge of the second lens 22 has press fit with the inner surface of the second barrel wall 12 of the lens barrel 1. Certainly, the first lens 21 and the second lens 22 can be also put directly into the lens barrel 1, having no press fit with the inner surface of the lens barrel 1. At last, the second lens 22 is fixed further by glue in the lens barrel 1. At this point, the assembling of the lens module 100 is finished.
The stop 3 can block off stray light. Moreover, the stop 3 can create directly the light hole 31 for the protruding central portion 213 of the first lens 21. The wall thickness of the first barrel wall 11 can be very thin, thereby the height and weight of entire lens module 100 are reduced, conforming to the miniaturization trend of equipment at present. At the same time, the lens barrel 1 with smaller wall thickness is convenient to be produced with high yield of qualified products and has other advantages.
It is to be understood, however, that even though numerous characteristics and advantages of the present embodiment have been set forth in the foregoing description, together with details of the structures and functions of the embodiment, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

## Claims

1. A lens module comprising:
a lens barrel having a central axis, including a first barrel wall extended at right angles to the central axis and a second barrel wall extended from the first barrel wall along the central axis;
a lens group including at least one lens located in the lens barrel, the at least one lens comprising a first surface close to the first barrel wall and a second surface opposite to the first surface; and
a stop clamped between the lens barrel and the at least one lens, wherein
the first surface of the at least one lens is provided with a first slope, an inner surface of the first barrel wall of the lens barrel is provided with a second slope abutting against the first slope, and the stop creates a light hole for the at least one lens.

2. The lens module according to claim 1, wherein the at least one lens comprises in turn from external to internal, as follows: a first flat surface extended horizontally, the first slope, a second flat surface extended horizontally and a first optical surface raised upward.

3. The lens module according to claim 2, wherein the inner surface of the first barrel wall comprises, in turn along the direction of the central axis of the lens barrel, as follows: a first flat surface extended horizontally, the second slope abutting against the first slope, and a second flat surface extended horizontally.

4. The lens module according to claim 2, wherein: the first surface of the at least one lens comprises a third flat surface lower than the second flat surface, and a gap is formed between the third flat surface and the stop.

5. The lens module according to claim 1, wherein the stop is a hollow ring.

6. The lens module according to claim 1, wherein an angle formed between the first slope and an optical axis of the at least one lens is equal to an angle between the second slope and the optical axis of the at least one lens.

7. The lens module according to claim 1, wherein an optical axis of the at least one lens, the central axis of the lens barrel and a central axis of the stop are aligned in one straight line.

8. The lens module according to claim 1, wherein the at least one lens comprises a protruding central portion and a peripheral portion around the protruding central portion, the protruding central portion extended along a direction of the central axis beyond the light hole.