IMAGING MODULE

An imaging module allows heated internal gas to escape out of a camera/imaging module when heat is applied to the module during an adhesive curing manufacturing step without making manufacture more difficult due to molding issues. The imaging module includes a lens holder with top and bottom surfaces. The bottom surface defines an opening at a bottom of the lens holder. The opening extends through the inside and outside walls of the lens holder. The opening allows heated internal gas to escape out of a camera/imaging module.

FIELD

The subject matter relates to imaging modules.

BACKGROUND

An imaging module (such as a camera module and a projection module) generally includes a circuit board, a lens holder, and a lens barrel. During assembly, the lens holder is fixed on the substrate. The lens barrel is accommodated and fixed in the lens holder. The lens barrel and the lens holder are generally fixed together by adhesive. After assembly, the imaging module needs to be heated to solidify the adhesive to ensure the fixing stability. Therefore, gas escape holes are designed in the lens holder to allow the release of the increased pressure of internal gases caused by heating, to prevent the imaging module from damage. However, the gas escape holes increase the difficulty of mold design, make the imaging module to be difficult to separate from the mold after molding, and affect the structural strength of the imaging module. Additionally, the gas escape holes need to be sealed after the heating process, which adds an additional production process.

Accordingly, there is room for improvement within the art.

DETAILED DESCRIPTION

In other instances, methods, procedures, and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features of the present disclosure.

One definition that applies throughout this disclosure will now be presented.

The term “substantially” is defined to be essentially conforming to the particular dimension, shape, or other feature that the term modifies, such that the component need not be exact. For example, “substantially rectangular” means that the object resembles a rectangle, but can have one or more deviations from a true rectangle.

The term “comprising,” when utilized, means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in the so-described combination, assembly, series, and the like.

FIGS. 1-2illustrate a first embodiment of a camera module100. The camera module100includes a fixed-focus camera module. The camera module100comprises a circuit board10, an image sensor20, a lens holder30, and a lens barrel40. The image sensor20and lens holder30are fixed to the circuit board10by adhesive.

The circuit board10comprises a first surface12and a second surface14. The first surface12and the second surface14are opposite to each other. In the embodiment, the circuit board10is a flexible circuit board. The first surface12is parallel to the second surface14.

The image sensor20is positioned on the first surface12, and is electrically connected to the circuit board10.

The lens holder30is fixed on the first surface12. In the embodiment, the lens holder40is made of plastic. The lens holder30is integrally formed. The image sensor20is received in the lens holder30. The lens holder40comprises a base32and a receiving portion34. The receiving portion34is connected to the base32.

The base32is substantially rectangular. The base32comprises a top surface322and a bottom surface324. The top surface322and the bottom surface324are opposite to each other. In the embodiment, the top surface322is parallel to the bottom surface324. A first groove420is defined in the base32. The first groove420extends through the top surface322and the bottom surface324. The first groove320is rectangular. The first groove320receives the image sensor20. An opening325is defined in the bottom surface324. The opening325allows internal gas to escape when heat is applied to the camera module100, thereby preventing damage to the camera module100resulting from the expansion of the internal gas. The opening325extends through the inner and outer sides of the side wall of the lens holder30. In the embodiment, the opening325is rectangular.

The receiving portion34is substantially cylindrical. A second groove340is defined in the housing portion34. The receiving portion34receives the lens barrel40. The second groove340extends through the housing portion34. The second groove340is cylindrical. The second groove340connects to the first groove320. A plurality of internal threads342is formed on the inner wall of the receiving portion34.

The lens barrel40is made of metal. The lens barrel40is received in the second groove340. A plurality of external threads42is formed on the outer wall of the lens barrel40. The external threads42match the internal threads342, thereby the lens barrel40is fixed in the second groove340.

During assembly, the lens holder30is fixed to the circuit board10. The image sensor20is fixed and electrically connected to the circuit board10. Then, the lens barrel40is positioned in the second groove340, and a position of the lens barrel40can be adjusted to align the central axis of the lens barrel40with a center of an imaging area of the image sensor20.

After assembly, the camera module100is placed in a heating device (not shown) for heat curing of the adhesive the adhesive. Because the opening325is defined in the lens holder30, heated gas inside the camera module100can escape out during the heating, thereby preventing damage to the camera module100caused by expansion of internal gas.

After the heating, an adhesive layer50is formed between the circuit board10and the outer wall of the lens holder30. The adhesive layer50fills the gap between the circuit board10and lens holder30, sealing opening325.

The camera module100further comprises a reinforcing plate60. The reinforcing plate60is glued to the second surface14of the circuit board10for enhancing the structural strength of the circuit board10. The adhesive for gluing the reinforcing plate60is the same as the adhesive of the adhesive layer50. Thus, the adhesive layer50can be formed together with the gluing of the reinforcing plate60. That is, the single extra step of sealing the opening325can be avoided. In the embodiment, the adhesive for gluing the reinforcing plate60is an ultraviolet-curable adhesive.

Referring toFIG. 3andFIG. 4, a camera module200of a second embodiment is provided. The difference from the camera module100is that the camera module200is a dual-lens and auto-focus camera module. The camera module200comprises a circuit board110, two image sensors120, a lens holder130, a voice coil motor140, and two lens barrels150. The lens holder130defines two grooves132for receiving the two image sensors120. Each groove132corresponds to one lens barrel150and one image sensor120. The two grooves132are spaced from each other. The opening1325is located at the bottom of the lens holder130close to the circuit board110, and between the two grooves132. The opening1325penetrates the inner and outer sides of the side wall of the lens holder130. The voice coil motor140is configured to drive the two lens barrels150to move within the camera module200. In the embodiment, each voice coil motor140defines a receiving groove (not shown). Each lens barrels150is accommodated in one receiving groove of the voice coil motor140.

Referring toFIG. 5andFIG. 6, a projection module300of a third embodiment is provided. The projection module300is used in a stereoscopic projector. The projection module300comprises a circuit board210, a ceramic substrate220, a laser emitter230, an electronic component240, a lens holder250, and a lens barrel260. The ceramic substrate is fixed on the circuit board210. The laser emitter230and the electronic component240are fixed on the ceramic substrate220. The lens holder250is positioned on the circuit board210and covers the ceramic substrate220. The lens barrel260is accommodated in the lens holder250. The projection module300functions by emitting laser light and receiving reflected laser light. An opening252is defined in the lens holder250. The opening252is located at the bottom of the circuit board210. The opening252penetrates the inner and outer sides of the side wall of the lens holder250. The shape, size, position, and functions of the opening252are the same as those of the opening325.

In the imaging modules (such as the camera modules100,200and the projection module300), the openings325,1325, and252are formed at the bottom of the lens holder30,130, and250, and are close to the circuit board10,110, and210. The openings325,1325, and252penetrate the inner and outer sides of the lens holders30,130, and250. Because the openings325,1325, and252are positioned at the bottoms of the lens holders30,130, and250, the manufacturing difficulty of the molding dies for molding the holders30,130, and250is reduced. After molding, the lens holders30,130, and250are more easily removable from their molds. Additionally, the openings325,1325, and252can be sealed together when the image module is glued to the reinforcing plate60. Thus, a single extra step for sealing the openings is avoided, thereby reducing the manufacturing cost.