Patent ID: 12249805

Reference numerals in the accompanying drawings are as follows:10—Fixing base;1—First surface;2—Second surface;11—First accommodation cavity;113—First inner wall;12—Second accommodation cavity;121—Second inner wall;13—Third accommodation cavity;131—Third inner wall;101—First fixing surface;102—Second fixing surface;111—First electrode;112—Second electrode;20—Light-emitting chip;21—Heat dissipation material/Thermal conductive material;23—Spherical solder;24—Copper pillar;30—Optical element;40—Substrate;401—Third electrode;402—Fourth electrode; and403—Thermal pad.

DESCRIPTION OF EMBODIMENTS

Characteristics and exemplary embodiments of various aspects of the present disclosure are described below in detail. In the following detailed descriptions, many specific details are provided to thoroughly understand the present disclosure. However, it is very clear to a person skilled in the art that the present disclosure can be implemented without some of these specific details. The following descriptions of the embodiments merely intend to provide examples of the present disclosure to better understand the present disclosure. The present disclosure is not limited to any specific configuration provided below, and instead covers any modification, replacement, and improvement of an element and a component without departing from the spirit of the present disclosure. In the accompanying drawings and the following descriptions, a well-known structure and technology are not shown to avoid unnecessary ambiguity of the present disclosure.

To better understand the present disclosure, a fixing base, a laser projection module, and an electronic device provided in the embodiments of the present disclosure will be described below in detail with reference toFIG.1toFIG.5.

Referring toFIG.1andFIG.2together, an embodiment of the present disclosure provides a fixing base10, applied to a laser projection module, where the fixing base10has a first surface1and a second surface2that are disposed oppositely in a height direction of the fixing base10; the second surface2is a light-emitting surface; the fixing base10includes a first accommodation cavity11, a second accommodation cavity12, and a third accommodation cavity13that are sequentially distributed in a direction from the first surface1to the second surface2and communicated to each other; a projection area of the second accommodation cavity12on the second surface2is greater than a projection area of the third accommodation cavity13on the second surface2and is smaller than a projection area of the first accommodation cavity11on the second surface2; a first inner wall113of the fixing base10is connected to a second inner wall121of the fixing base10via a first fixing surface101; the second inner wall121is connected to a third inner wall131of the fixing base10via a second fixing surface102; the first inner wall113is formed by the first accommodation cavity11in the fixing base10; the second inner wall121is formed by the second accommodation cavity12in the fixing base10; the third inner wall131is formed by the third accommodation cavity13in the fixing base10; and the fixing base10is provided with a conduction line.

As an optional implementation, the fixing base10is a structural member made of a ceramic material or resin material, which is implemented, for example, by using an injection molding process. During injection molding, a copper sheet or copper wire constituting a circuit is laid and embedded into the fixing base10.

As an optional implementation, the fixing base10is a structural member made by embedding a metal frame into a ceramic material or resin material, which is implemented, for example, by using an injection molding process. During injection molding, a copper sheet or copper wire constituting a circuit is laid and embedded into the fixing base10, and the metal frame is embedded into the fixing base10at the same time. The metal frame can improve structural strength of the fixing base10.

The conduction line can alternatively be laid on a surface of an inner wall of the fixing base and bonded onto the inner wall by using an adhesive. One terminal of the conduction line is connected to the light-emitting chip, and the other terminal of the conduction line extends out of the fixing base and is connected to an external circuit.

Referring toFIG.1toFIG.3together, an embodiment of the present disclosure further provides a laser projection module, including: a light-emitting chip20, an optical element30, and any one of the foregoing fixing bases10.

The light-emitting chip20is disposed on the first fixing surface101of the fixing base10and is electrically connected to one terminal of the conduction line.

The light-emitting chip20may be an edge-emission laser chip such as a distributed feedback laser (DFB) chip. The DFB chip includes a single light source, or a plurality of DFB chips are arranged in an array to form a multi-point light source. The edge-emission laser chip has a low temperature drift, which can reduce an impact of temperature on a laser effect.

The light-emitting chip20may alternatively be a vertical cavity surface emitting laser (VCSEL) chip. The VCSEL chip includes a plurality of light sources arranged in an array. The VCSEL chip has a small height, helping reduce a height of the laser projection module, and facilitating integration of the laser projection module into an electronic device such as a mobile phone that has a higher thickness requirement.

The optical element30is disposed on the second fixing surface102of the fixing base10, for example, may be attached onto the second fixing surface102by using a fixing glue. After passing through the optical element30, laser light emitted by the light-emitting chip20is projected out of the fixing base10through the third accommodation cavity13of the fixing base10.

As described above, the second surface2of the fixing base10is a light-emitting surface. The optical element30is attached into the inverted fixing base10, thereby being not easy to get loose due to an external collision. Even if the optical element30gets loose, the optical element30can still be stuck inside the fixing base10instead of coming off, thereby preventing laser light emitted by the light-emitting chip20from directly irradiating a human body to cause harm. In addition, an additional protective cover does not need to be disposed on an outer side of the optical element30of the laser projection module, which reduces an overall height of the laser projection module.

In some embodiments, the optical element30may be a diffuser. After passing through the diffuser and being diffused by the diffuser, laser light emitted by the light-emitting chip20is projected out through the third accommodation cavity13of the fixing base10, for example, projected into a target space to form a laser pattern.

In some embodiments, the optical element30includes a diffractive element accommodated in the fixing base10, and optionally further includes a collimating element. The collimating element is disposed between the light-emitting chip20and the diffractive element and is configured to collimate laser light passing through the collimating element. The diffractive element is configured to project laser light collimated by the collimating element out through the third accommodation cavity13of the fixing base10, to form a laser pattern.

Further, the shapes of orthogonal projections of the first accommodation cavity11, the second accommodation cavity12, and the third accommodation cavity13on the second surface are square or circular. Depth dimensions of the first accommodation cavity11, the second accommodation cavity12, and the third accommodation cavity13are determined according to specific types of the light-emitting chip20and the optical element30. Details are not described herein again.

According to the laser projection module provided in this embodiment of the present disclosure, the optical element30and the light-emitting chip20are disposed in the inverted fixing base10, which can prevent the optical element30from coming off from the fixing base10, thereby preventing laser light emitted by the light-emitting chip20from directly irradiating a human body to cause harm, and improving safety of the laser projection module.

Referring toFIG.1toFIG.3again, the light-emitting chip20is welded on the first fixing surface101of the fixing base10by using a spherical solder23. In comparison with a connection manner of wire bonding for the light-emitting chip20, a manufacture cost can be reduced. In addition, an overall dimension of the laser projection module can be reduced, making a structure more compact.

The light-emitting chip20has higher heat productivity. Therefore, to facilitate heat dissipation, one side of the light-emitting chip20away from the first fixing surface101is provided with a heat dissipation material21, for example, coated with a heat dissipation adhesive. Heat generated by the light-emitting chip20can be dissipated through the heat dissipation material21, preventing the laser projection module from overheating.

In some embodiments, the first surface1of the fixing base10is provided with an electrode or coated with an electrically conductive material. The electrode includes a first electrode111and a second electrode112that are distributed on the first surface1at an interval. The laser projection module is electrically connected to the outside via the electrode or the electrically conductive material.

The laser projection module is structurally the weakest at a position where the first surface1of the fixing base10is connected to a peripheral component. When the laser projection module is impacted by an external force, damage first occurs at a position where the first surface1is electrically connected to the outside. Once damage occurs at the position, a circuit of the light-emitting chip20is damaged. Consequently, the light-emitting chip20stops working and does not emit laser light, further improving the safety of the laser projection module.

Referring toFIG.4, an embodiment of the present disclosure further provides a laser projection module, which has a structure similar to the laser projection module shown inFIG.3. A difference lies in that the laser projection module in this embodiment further includes a substrate40electrically connected to the first surface1of the fixing base10. A surface of the substrate40facing away from the fixing base10is provided with an electrode or coated with an electrically conductive material. The electrode includes a third electrode401and a fourth electrode402that are distributed on the substrate40at an interval. The laser projection module is electrically connected to the outside via the electrode or the electrically conductive material.

The first surface1of the fixing base10may be welded together with the substrate40by using, for example, solder paste. The substrate40is connected to the light-emitting chip20via a circuit laid in the fixing base10, so that the light-emitting chip20can emit laser light. The light-emitting chip20has higher heat productivity. To facilitate heat dissipation, optionally, a surface of the substrate40facing the light-emitting chip20is provided with a thermal pad403extending towards the light-emitting chip20. The thermal pad403is tightly attached to the light-emitting chip20, so that heat generated by the light-emitting chip20can be conducted outside via the substrate40.

Optionally, one side of the light-emitting chip20away from the first fixing surface101is provided with a thermal conductive material21, for example, a thermal conductive adhesive or thermal conductive pad. Heat generated by the light-emitting chip20is dissipated via the thermal conductive adhesive or the thermal conductive pad.

Optionally, the substrate40is a plate made of a thermal conductive material. Therefore, the substrate40not only can be applied to a bearer circuit, but also can dissipate heat of the light-emitting chip20, thereby improving service life of the laser projection module. The thermal conductive material may be a ceramic material, or may be a metallic material, for example, aluminum, gold, copper, silver, or the like. Therefore, high heat conductivity of thermal conductive materials such as the ceramic material, the metallic material, and the like can be fully utilized to dissipate heat of the light-emitting chip20.

In some embodiments, the substrate40may alternatively be made of plastic, for example, at least one of: polyethylene glycol terephthalate (PET), polymethyl methacrylate (PMMA), polycarbonate (PC), and polyimide (PI). Therefore, the substrate40has a small weight but sufficient support strength.

Optionally, one or more heat dissipation holes are formed in the substrate40and filled with a thermal conductive material. The heat dissipation hole may be circular, rectangular, or the like. The heat dissipation holes may be arranged in an array on the substrate40, or may be arranged densely at a position close to the light-emitting chip20. The heat dissipation hole is filled with a thermal conductive material (for example, thermal silicone grease, a metallic material, or the like) to enhance a thermal conduction effect.

When the substrate40is made of ceramic and the foregoing heat dissipation hole is formed in the substrate40, the heat dissipation hole is filled with thermal silicone grease or a metallic material (for example, silver, copper, gold, or the like) to dissipate heat. When the substrate40is made of a metallic material and the foregoing heat dissipation hole is formed in the substrate40, the heat dissipation hole is filled with metal with higher thermal conductivity than the metallic material. For example, when the substrate40is made of aluminum, the heat dissipation hole is filled with copper. For another example, when the substrate40is made of copper, the heat dissipation hole is filled with gold. In this way, the thermal conductivity of the substrate40may be improved, and a cost of the substrate40may be reduced. When the substrate40is made of plastic and the foregoing heat dissipation hole is formed in the substrate40, the heat dissipation hole is filled with thermal silicone grease or a metallic material. In this case, the substrate40provides not only a support function but also a heat dissipation function, and the substrate40is light.

In addition, the laser projection module is structurally the weakest at a position where the first surface1of the fixing base10is electrically connected to the substrate40or at a position where the electrode of the substrate40is electrically connected to the outside. When the laser projection module is impacted by an external force, damage first occurs at the position where the first surface1is electrically connected to the substrate40or at the position where the electrode of the substrate40is electrically connected to the outside. No matter the damage occurs at which of the positions, a circuit of the light-emitting chip20is damaged. Consequently, the light-emitting chip20stops working and does not emit laser light, further improving safety of the laser projection module.

Referring toFIG.5, the light-emitting chip20of any one of the foregoing laser projection modules according to the embodiments of the present disclosure can be welded on the first fixing surface101of the fixing base10by using a copper pillar24having a dome-shaped solder at the top. When the copper pillar24is used, more external electrical connection points can be arranged on the light-emitting chip20with a smaller size, and welding spots can be arranged more densely in a unit area, thereby obtaining a laser projection module with higher integration, smaller crosstalk interference, and lower noise.

In addition, an embodiment of the present disclosure further provides an electronic device, including any one of the foregoing laser projection modules. The electronic device may be a mobile phone, a tablet computer, a portable computer, a game console, a head mounted display device, an access control system, a teller's machine, or the like.

It should be understood by a person skilled in the art that the foregoing embodiments are merely exemplary rather than restrictive. Different technical features in different embodiments may be combined to achieve beneficial effects. On the basis of studying the accompanying drawings, the specifications, and the claims, a person skilled in the art, shall be able to understand and implement other modified embodiments of the disclosed embodiments. In the claims, the term “comprise” does not exclude other apparatuses or steps; when an article is not modified with a quantifier, it is intended to include one/one type or multiple/multiple types of articles, and can be used interchangeably with “one/one type or multiple/multiple types of articles”; and the terms “first” and “second” are used to indicate names rather than to indicate any particular order. None of the reference signs in the claims shall be construed as limiting the protection scope. The functions of the multiple parts appearing in the claims may be implemented by a single hardware or software module. The appearance of certain technical features in different dependent claims does not mean that these technical features cannot be combined to achieve beneficial effects.