Lens module and electronic device including gas escape structure

A lens module includes a circuit board, a carrier, and an optical filter. The carrier is fixed on a surface of the circuit board. The carrier defines a through hole. The optical filter is mounted on the carrier. The carrier defines at least one gas escape structure. A receiving space is between the optical filter and the circuit board, and the gas escape structure communicates with the receiving space to release water vapor in the receiving space and allow air pressure equalization and thus the relief of stress. The disclosure further provides an electronic device including the lens module.

FIELD

The subject matter relates to imaging.

BACKGROUND

Portable electronic devices, such as cell phones, tablet computers, and multimedia players, usually include lens modules. The lens module includes a lens, an optical filter, a bracket, an image sensor, and a circuit board. The optical filter is mounted to the bracket through adhesive, and the adhesive is solidified by curing. However, water vapor generated during curing may not be able to escape from the bracket, which may form water mist or droplets on the surfaces of the optical filter and the image sensor. Thus, the image quality of the lens module is lowered. In addition, during curing, the air in the lens module is expanded and causes stress, which further lowers the imaging quality of the lens module.

DETAILED DESCRIPTION

FIGS. 1 to 3illustrate an embodiment of a lens module100. The lens module100includes a circuit board10, an optical filter30, a carrier40, a lens holder60, and a lens70.

In an alternative embodiment, the circuit board10can be a flexible board, a rigid board, or a rigid-flexible board. In an alternative embodiment, the circuit board10is a rigid-flexible board that includes a first rigid board portion11, a second rigid board portion12, and a flexible board portion13arranged between the first rigid board portion11and the second rigid board portion12. A first surface of the second rigid board portion12carries an electrical connection portion20. When the lens module100is connected to an electronic device through the electrical connection portion20, the electrical connection portion20is configured to implement signal transmission between the lens module100and an electronic device (not shown). The electrical connection20can be a gold fingers connector (edge connector) or other connector. A second surface of the second rigid board portion12carries a reinforcing plate14. The reinforcing plate14is made of metal (such as stainless steel).

The lens module100further includes an image sensor21and a plurality of electronic components22. The image sensor21and the electronic components22are mounted on a first surface of the first rigid board portion11. The image sensor21, the electronic components22, and the electrical connection portion20are located on a same surface of the circuit board10. Each electronic component22can be a passive component such as a resistor, a capacitor, a diode, a transistor, a relay, or an electrically erasable programmable read only memory (EEPROM).

The carrier40is mounted on the first surface of the first rigid board portion11of the circuit board10. The carrier40, the image sensor21, the electronic components22, and the electrical connection portion20are located on the same surface of the circuit board10. The carrier40is a hollow rectangular structure. The carrier40defines a through hole41. The carrier40defines a first surface away from the circuit board. An area of the first surface of the carrier40adjacent to the through hole41is recessed inwardly to form a groove42. The first surface of the carrier40further defines a gas escape structure43. The gas escape structure43is generally L-shaped, and includes a first escape structure portion431and a second escape structure portion432. The first escape structure portion431is a slot that is defined at a sidewall of the groove42and defines an opening44on the first surface of the carrier40. The second escape structure portion432is also a slot that is defined at the bottom of the groove42and communicates with the first escape structure portion431. The carrier40can be made of metal or plastic. In an alternative embodiment, the carrier40is made of plastic.

Referring toFIG. 4andFIG. 5, the optical filter30is mounted in the groove42of the carrier40through an adhesive layer50, and is spaced away from the image sensor21. In an alternative embodiment, the optical filter30is rectangular. The optical filter30and the circuit board10close opposite ends of the through hole41to form a receiving space401. The gas escape structure43connects the receiving space401to the opening44. In an alternative embodiment, during assembly, the optical filter30is first fixed in the groove42of the carrier40by an adhesive (not shown). The adhesive is then cured to form the adhesive layer50, thereby causing the optical filter30to be fixed in the groove42of the carrier40. The escape structure43is configured to allow water vapor generated in the receiving space401to escape through the opening44, which prevents the formation of water mist or water droplets on the surface of the optical filter30and the image sensor21, and further improves the image quality of the lens module100. In addition, the gas escape structure43is also capable of relieving stress generated by pressure build-up, thus the imaging quality of the lens module100is further ensured.

The lens holder60is mounted on the first surface of the carrier40. The lens holder60has a hollow rectangular structure and defines a receiving hole61(shown inFIG. 3). The lens holder60is made of metal or plastic. In an alternative embodiment, the lens holder60is made of plastic. During curing the adhesive, the water vapor escapes through the opening. After the adhesive is cured the lens holder60is then mounted on the first surface of the carrier40. The lens holder60can close the opening44to prevent dust from outside entering the interior of the lens module100through the opening44.

The lens70is partially received in the receiving hole61of the lens holder60. The lens70and the lens holder60can be formed separately or as an integral unit. In an alternative embodiment, the lens70and the lens holder60are integral. The lens70includes a first lens portion71and a second lens portion72. A diameter of the first lens portion71is greater than the diameter of the second lens portion72. The lens70can be assembled (that is, the first lens portion71and the second lens portion72are separate items assembled to each other) or can be integrally formed. In an alternative embodiment, the first lens portion71and the second lens portion72of the lens70are integrally formed to form the lens70. The first lens portion71is partially received in the receiving hole61(shown inFIG. 3).

In an alternative embodiment, the groove42can be omitted. The optical filter30can be directly mounted on the carrier40or be mounted in the through hole41of the carrier40. For example, adhesive can be applied to the outer peripheral wall of the optical filter30and the inner peripheral wall of the carrier40to mount the optical filter30to the carrier40. The optical filter30and the carrier40can also be mounted together by a simple friction (interference) fit. The optical filter30and the carrier40can also be mounted together by other manners.

The structure of the gas escape structure43can be varied according to need. For example, the gas escape structure43can be a straight through hole defined on a sidewall of the carrier40, as long as the through hole can communicate with the receiving space401to allow escape of water vapor.

FIG. 6illustrates an embodiment of an electronic device200. The electronic device200includes the lens module100. The electronic device200can be any electronic device having imaging capturing functions, such as mobile phones, wearable devices, computer devices, vehicles, or monitoring devices. In an alternative embodiment, the electronic device200is a mobile phone.

The gas escape structure43defined on the carrier40functions as a passage communicating with the receiving space401, to allow the release of water vapor and the relief of stress caused by unequal air pressures. Thereby the imaging quality of the lens module100is improved.