Patent Application
20150233541
1. Technical Field
The present invention relates generally to a light source, and more particularly to a light source module, which emits light with a large divergence angle.
2. Description of Related Art
As the improvement of technology, light source modules, which are powered by electricity, are widely used for illumination in ordinary life. In recent days, LED (light emitting diode) module is the commonest light source module in the market.
In view of the above, the primary objective of the present invention is to provide a light source module, which emits light with a large divergence angle.
The present invention provides a light source module, including a lighting member and an optical member. The optical member is transparent and is made of a light curable material or a thermosetting material. The optical member covers the lighting member. The optical member has a first optical layer and a second optical attached to the first optical layer. A refractive index of the first optical layer is greater than 1, and a refractive index of the second optical layer is greater than 1 and is not identical to the refractive index of the first optical layer.
In an embodiment, the refractive indexes of the first optical layer and the second optical layer are in a range between 1.2 and 2.0.
In an embodiment, a difference of the refractive indexes of the first optical layer and the second optical layer is in a range between 0.01 and 0.5.
In an embodiment, curvatures of surfaces of first optical layer and the second optical layer which are attached to each other are different from a curvature of a surface of the first optical layer which faces the light member.
In an embodiment, curvatures of surfaces of the first optical layer and the second optical layer which are attached to each other are different from a curvature of a surface of the second optical layer which faces outside of the light source module.
In an embodiment, an air medium is formed between the light member and the first optical layer.
In an embodiment, a difference of the refractive index of the first optical layer and a refractive index of the air medium is in a range between 0.1 and 1.0.
With the aforementioned design, the light source module of the present invention may have a large light diverging capacity to emit light in a wide angle.
The present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which
As shown in
The lighting member 10 has a substrate 12 and a LED (light emitting diode) chip 14 mounted on the substrate 12. The LED chip 14 is powered by electricity to emit light. In practice, except for the LED chip 14, any lighting device may be used in the present invention.
The optical member 20 is transparent, and is mounted on the substrate 12 to cover the LED chip 14. A space is formed between the LED chip 14 and the optical member 20, and the space is filled with air. In other words, an air medium G is formed between the LED chip 14 and the optical member 20. The optical member 20 has a first optical layer 21 and a second optical layer 22 attached to the first optical layer 21 by adhesive or other means, wherein the first optical layer 21 is proximal to the LED chip 14. In an embodiment, the first and the second optical layers 21 and 22 are made of epoxy, which is self-adhesive and UV curable. The second optical layer 22 is attached to the first optical layer 21 while the second optical layer 22 is being solidified, or the first optical layer 21 is attached to the second optical layer 22 while the first optical layer 21 is being solidified. Refractive indexes of the first and the second optical layers 21 and 22 are greater than one, and the refractive index of the first optical layer 21 is not equal to that of the second optical layer 22. In an embodiment, the refractive indexes of the first and the second optical layers 21 and 22 are in a range between 1.2 and 2.0, and a difference of the refractive indexes of the first and the second optical layers 21 and 22 is in a range between 0.01 and 0.5. A difference of the refractive index of the first optical layer 21 and a refractive index of the air medium G is in a range between 0.1 and 1.0. Except epoxy, any light curable or thermosetting material may be used to mold the first and the second optical layers 21 and 22.
Besides, surfaces S2 of the first and the second optical layers 21 and 22 which are attached to each other have complementary curvatures, which mean no gap between the surfaces S2. The curvatures of the surfaces S2 are different from that of a surface S1 of the first optical layer 21 which faces the LED chip 14 and that of a surface S3 of the second optical layer 22 which faces outside of the light source module 1. With these characters, the optical member 20 may have a large light diverging capacity to diverge light in a wide angle.
As a result, the double-layered optical member 20 may have a divergence angle in a range between 165 degrees and 170 degrees to enlarge the range where the light source module 1 may illuminate.
It must be pointed out that the embodiments described above are only some preferred embodiments of the present invention. All equivalent structures and methods which employ the concepts disclosed in this specification and the appended claims should fall within the scope of the present invention.
