Patent Description:
This section is intended to provide a background or context for specific embodiments of the present disclosure recited in the claims. The description here is not admitted to be prior art just because it is included in this section.

At present, a solid-state light source used in the lighting field uses a blue laser and phosphors to output white light. The blue laser can operate at high drive power densities and produce relatively high luminous flux. A light source using the blue laser can have brightness which is dozens of times higher than that of an LED. For applications with strict restrictions in volume and etendue, the blue laser has inherent advantages as light sources.

At present, the solid-state light sources with the blue laser still have certain technical problems, such as heat dissipation problems of a blue laser chip and a wavelength conversion layer.

<CIT>, <CIT>and <CIT> are all directed to lighting devices including a laser light source.

The present disclosure provides a light source system and a lighting device which can solve the heat dissipation problems of an internal laser and a wavelength conversion layer.

A lighting device includes the above light source system.

In the light source system and the lighting device including the light source system provided by the present disclosure, the substrate in the light source system is made of material with a high thermal conductivity, the laser is received in the substrate, and heat of the wavelength conversion layer is transferred to the substrate through the reflective layer, thereby solving the heat dissipation problems of the laser and the wavelength conversion layer in the light source system. In addition, since the laser and the wavelength conversion layer are located in the same notch, the light source system and the lighting device each have a small volume and each have a simple and compact structure.

The following specific embodiments will further illustrate the present disclosure with reference to the above drawings.

Referring to <FIG>, <FIG> is a three-dimensional schematic diagram of a light source system <NUM> provided by a first embodiment of the present disclosure, <FIG> is a cross-sectional view of the light source system <NUM> shown in <FIG> taken along a line II-II, and <FIG> is a top view of the light source system shown <NUM> shown in <FIG>. The light source system <NUM> provided by the embodiment of the present disclosure includes a substrate <NUM>, a light guiding element <NUM>, a laser <NUM>, a beam deflecting device <NUM>, a wavelength conversion layer <NUM>, and a reflective layer <NUM>.

The light source system <NUM> in this embodiment includes at least one laser <NUM> configured to emit excitation light. The substrate <NUM> is made of material with a high thermal conductivity, and the material with a high thermal conductivity can be aluminum nitride, silicon nitride, silicon carbide, boron nitride, or metal such as copper or aluminum. The substrate <NUM> is provided with a notch <NUM>, and the laser <NUM> is received in a sidewall of the notch <NUM>, thereby solving a heat dissipation problem of the laser <NUM>. In addition, the laser <NUM> and the wavelength conversion layer <NUM> are located in a same notch <NUM>, and the light source system <NUM> and a lighting device to which the light source system <NUM> is applied have a small volume and a simple and compact structure.

The beam deflecting device <NUM> and the laser <NUM> are provided in one-to-one correspondence, and the beam deflecting device <NUM> is configured to guide the excitation light emitted by a laser <NUM> corresponding the beam deflecting device <NUM> to be irradiated to the wavelength conversion layer <NUM>. The beam deflecting device <NUM> can be a prism, an aspheric lens, a free arc-shaped surface, a reflective mirror, and so on.

The reflective layer <NUM> can be a diffuse reflective layer or a metal reflective layer, covers a wall of the notch <NUM> and is configured to reflect light, to improve a light emission efficiency of the light source system <NUM>.

The wavelength conversion layer <NUM> is provided on a part of a surface of the reflective layer <NUM> and is configured to perform wavelength conversion on the excitation light to obtain excited light. The wavelength conversion layer <NUM> transfers heat to the substrate <NUM> via the reflective layer <NUM> and dissipates the heat through the substrate <NUM>, thereby solving the heat dissipation problem of the wavelength conversion layer <NUM>.

The light guiding element <NUM> covers an opening of the notch <NUM> and is configured to reflect the excitation light and transmit the excited light, and the excited light is emitted from the light guiding element <NUM> to obtain light source light to be emitted by the light source system <NUM>.

The substrate <NUM> of the light source system <NUM> is made of material with a high thermal conductivity, and the laser <NUM> is received in the wall of the substrate <NUM>. The heat generated by the wavelength conversion layer <NUM> is transferred to the substrate <NUM> via the reflective layer <NUM>, thereby solving the heat dissipation problems of the laser <NUM> and the wavelength conversion layer <NUM> of the light source system.

In addition, the light source system <NUM> adopts the laser <NUM>, and the laser <NUM> and the wavelength conversion layer <NUM> are received in the notch <NUM> of the same substrate <NUM>, so that the light source system <NUM> not only has high light emission brightness, but also has a small volume. The light source system <NUM> can also be applied to a lighting equipment, and the lighting device provided by the embodiment of the present disclosure can be applied in the fields of automobile lamp devices, stage lights, and laser headlights.

In the first embodiment, the light source system <NUM> includes four identical lasers <NUM>. The laser <NUM> can be a blue laser configured to emit blue excitation light. It can be understood that the laser <NUM> is not limited to the blue laser, and the laser <NUM> can also be an ultraviolet laser, a red laser, a green laser, or the like. It can be understood that the light source system <NUM> can include one or two blue lasers or a blue laser array, and the specific number of the lasers <NUM> of the light source system 100can be selected according to actual needs.

The notch <NUM> has a shape of a frustum, and the wall of the notch <NUM> includes four sidewalls 111a and one bottom wall 111b. The laser <NUM> is exposed at a surface of the substrate <NUM>, and any two lasers <NUM> are received in different sidewalls 111a of the notch <NUM>. Each beam deflecting device <NUM> is disposed between the laser <NUM> corresponding to the beam deflecting device <NUM> and the light guiding element <NUM>.

It can be understood that, in an embodiment, the light source system <NUM> includes less than four lasers <NUM>, for example, three lasers <NUM>. Each of any three sidewalls 111a of the notch <NUM> can be provided with a laser <NUM>. Alternatively, two of the three lasers <NUM> are disposed on one sidewall 111a and the remaining one laser <NUM> is disposed on another sidewall 111a. In an alternative that does not form part of the present invention, the three lasers <NUM> are all disposed on any one sidewall 111a if heat dissipation conditions allow. Due to a reflective effect of the reflective layer <NUM> and filtering characteristics of the light guiding element <NUM>, the excitation light can excite the wavelength conversion layer <NUM> to generate the excited light, and the excited light is emitted from the light source system <NUM> to obtain the light source light.

The wavelength conversion layer <NUM> is provided with yellow phosphors and configured to generate yellow excited light. The yellow excited light is emitted from the light guiding element <NUM> to obtain yellow light source light.

The wavelength conversion layer <NUM> is provided on the reflective layer <NUM> at the bottom wall 111b. The yellow excited light emitted by the wavelength conversion layer <NUM> and unconverted blue excitation light are directly incident to the light guiding element <NUM>. Under the reflection of the light guiding element <NUM> and the reflective layer <NUM>, the unconverted part of the excitation light can excite the wavelength conversion layer <NUM> multiple times until it is converted into excited light and emitted through the light guiding element <NUM>. It can be understood that, in alternatives that do not form part of the present invention, the wavelength conversion layer <NUM> can be disposed on the reflective layer <NUM> at any position of the sidewall 111a, or any positions provided on multiple walls or a partial region of any wall of the notch <NUM>. In addition, the wavelength conversion layer <NUM> can be configured to generate excited light of other colors under the excitation of the excitation light, such as red and green excited light. That is, the wavelength conversion layer <NUM> is provided with a red fluorescent material and a green fluorescent material in sections, so that optical power of the generated red excited light and that of the green excited light can reach a preset ratio. It can be understood that, in other embodiments, the wavelength conversion layer <NUM> can also be provided with yellow and green fluorescent materials, or yellow and red fluorescent materials, or yellow, red, and green fluorescent materials, and it is not limited to this.

In addition, the wavelength conversion layer <NUM> has a rough surface, to improve the light emission efficiency of the wavelength conversion layer <NUM> and reduce reflection loss when the excitation light glides at a large angle.

The reflective layer <NUM> is disposed on the wall, that is, the reflective layer <NUM> covers four sidewalls 111a and one bottom wall 111b, so as to reflect the light therein from various directions in the light source system <NUM>, thereby increasing the number of the light reflection and improving a conversion efficiency of the excitation light. In addition, the light in the notch <NUM> can only be emitted from the light guiding element <NUM>, which ensures the light emission efficiency of the light source system <NUM>.

In this embodiment, the light guiding element <NUM> is configured to reflect the excitation light and transmit the excited light, and the light guiding element <NUM> can be a beam-splitting filter plated with a blue-reflective and yellow-transmissive film. It can be understood that in an embodiment, the light guiding element <NUM> is a prism provided with an optical film, and the prism facilitates multiple reflections of the excitation light in the light source system <NUM>. In other embodiments, the light guiding element <NUM> can be coated according to the colors of the excitation light and the excited light.

It can be understood that, in an embodiment, the notch <NUM> can have a shape with which its opening and the bottom wall 111b have different areas. Preferably, an area of the bottom wall 111b is smaller than the area of the opening, such as a circular frustum shape, a circular cone shape, a pyramid shape, or other irregular shapes such as a shape having a U-shaped or V-shaped cross-section,, in order to ensure that the unconverted part of the excitation light emitted from the wavelength conversion layer <NUM> is incident to the light guiding element <NUM>, then the excitation light is reflected, and it is reflected by the reflective layer <NUM> to the wavelength conversion layer <NUM> and converted into excited light, which is then emitted from the light guiding element <NUM>, so that it is also ensured that the excitation light that is not irradiated to the wavelength conversion layer <NUM> is guided to the wavelength conversion layer <NUM> through the reflective layer <NUM> and the light guiding element <NUM> to be converted into excited light, which is finally emitted from the light guiding element <NUM>.

In some possible implementations, the wavelength conversion layer <NUM> is disposed on the bottom wall of the U-shaped notch.

Referring to <FIG>, <FIG> is a cross-sectional view of a light source system <NUM> provided by a second embodiment of the present disclosure, <FIG> is a top view of the light source system <NUM> shown in <FIG>, and <FIG> is a schematic diagram of spots on a wavelength conversion layer <NUM> shown in <FIG>.

The cross-sectional view of the light source system <NUM> provided in the embodiment as shown in <FIG> is obtained in the same manner as the light source system <NUM>.

A difference between the light source system <NUM> and the light source system <NUM> mainly lies in: the laser <NUM> in the light source system <NUM> is received in the sidewall 211a of the notch <NUM> of the substrate <NUM> at a preset angle, in such a manner that the excitation light emitted by the laser <NUM> propagates along a straight line to be irradiated to the wavelength conversion layer <NUM>, and the beam deflecting device is omitted. It should be noted that specific solutions applicable to the first embodiment can also be correspondingly applied to the second embodiment and will not be repeated herein to save space and avoid duplication.

Specifically, as shown in <FIG> and <FIG>, the laser <NUM> is at a certain angle with respect to the bottom wall 211b in a perpendicular direction, in such a manner that the excitation light emitted by the laser <NUM> propagates along a straight line to be irradiated to the wavelength conversion layer <NUM>, thereby omitting the beam deflecting device; as shown in <FIG>, the laser <NUM> is at a certain angle with respect to the sidewall 211a in a horizontal direction, in such a manner that spots formed on the wavelength conversion layer <NUM> by any two lasers <NUM> partially overlap and partially do not overlap, and then spots emitted by the lasers <NUM> can be more uniformly irradiated on the wavelength conversion layer <NUM>, which can avoid a problem that a conversion efficiency of the wavelength conversion layer <NUM> is reduced due to excessive local heat of the wavelength conversion layer <NUM>. The laser spots irradiated on the wavelength conversion layer <NUM> are as shown in <FIG>.

The light source system <NUM> provided in the second embodiment can solve the heat dissipation problems of the laser <NUM> and the wavelength conversion layer <NUM>, and the light source system <NUM> and a lighting device to which the light source system <NUM> is applied have a small volume and a simple and compact structure. In addition, the number of optical devices used in the light source system <NUM> is reduced, an internal space of the light source system <NUM> is saved, and the cost is lower.

Referring to <FIG>, which is a cross-sectional view of a light source system <NUM> provided by a third embodiment of the present disclosure as shown in <FIG>.

A difference between the light source system <NUM> and the light source system <NUM> mainly lies in: the laser <NUM> of the light source system <NUM> emits excitation light in a first polarization state, the wavelength conversion layer <NUM> changes a polarization state of the excitation light, the light guiding element <NUM> is a polarizing prism plated with an optical film, the polarizing prism is configured to reflect light of the first polarization state and transmit light of another polarization state, that is, the polarization state of the excitation light of the first polarization state is changed by the wavelength conversion layer <NUM>, and the excitation light of the first polarization state is finally emitted from the light guiding element <NUM> in forms of other polarization states, excited light of other polarization states is also emitted from the light guiding element <NUM>, and blue excitation light and yellow excited light that are emitted from the light guiding element <NUM> are combined to obtain white light source light. It should be noted that various specific solutions applicable to the first embodiment can also be correspondingly applied to the second embodiment and will not be repeated herein in order to save space and avoid duplication.

Claim 1:
A light source system (<NUM>, <NUM>, <NUM>), comprising:
at least two lasers (<NUM>, <NUM>, <NUM>) configured to emit excitation light;
a substrate (<NUM>, <NUM>) made of material with a high thermal conductivity, wherein the substrate (<NUM>, <NUM>) is provided with a notch (<NUM>, <NUM>), a wall (111a, 211a, 111b, 211b) of the notch (<NUM>, <NUM>) comprises a bottom wall (111b, 211b) and sidewalls (111a, 211a), and the at least two lasers (<NUM>, <NUM>, <NUM>) are received in different sidewalls (111a, 211a);
a reflective layer (<NUM>, <NUM>) covering the wall (111a, 211a, 111b, 211b) of the notch (<NUM>, <NUM>) and configured to reflect the excitation light;
a wavelength conversion layer (<NUM>, <NUM>, <NUM>) provided on a surface of the reflective layer (<NUM>, <NUM>) covering the bottom wall (111b, 211b) and configured to perform wavelength conversion on the excitation light to obtain excited light; and
a light guiding element (<NUM>, <NUM>) covering an opening of the notch (<NUM>, <NUM>) and configured to reflect the excitation light and transmit the excited light, to obtain light to be emitted by the light source system (<NUM>, <NUM>, <NUM>).