[0053] Fig. 3 is a schematic diagram of a light-emitting unit according to an embodiment of the present invention. 3, the light-emitting unit 300 of this embodiment includes a light-emitting diode light source module 310 and a lens structure 400, wherein the lens structure 400 is disposed on the light-emitting diode light source module 310. The lens structure 400 includes a lens body 410, and the lens body 410 has a light incident surface 412, a light output surface 414 and a reflective surface 416. The light incident surface 412 is opposite to the light output surface 414, and the reflective surface 416 has a conical shape and is connected between the light incident surface 412 and the light output surface 414. The area of the light incident surface 412 is smaller than the area of the light output surface 414, and the light output surface 414 is a concave curved surface.
[0054]In the aforementioned lens structure 400, the light incident surface 412 is a flat surface, and the light incident surface 412 faces the LED light source module 310. The radius of curvature of the light-emitting surface 414 is, for example, between 78.44 mm and 252.5 mm. In addition, the light-emitting diode light source module 310 includes, for example, red light-emitting diodes, blue light-emitting diodes, and green light-emitting diodes. The LED light source module 310 is used to provide light 312, a part of the light 312 will be transmitted to the reflecting surface 416, and the other part of the light 312 will enter the lens body 410 through the light incident surface 412, and leave the lens body 410 through the light exit surface 414. In addition, the reflective surface 416 can reflect the light 312 by the principle of total reflection. In this embodiment, a reflective material layer 420 can also be coated on the reflective surface 416 to reflect the light 312.
[0055] Since among the light 312 provided by the LED light source module 310, the light 312 closer to the optical axis 311 has a higher energy, so the energy of the light 312 entering the lens body 410 is higher than that reflected by the reflective surface 416 or the reflective material layer 420 The energy of light 312. However, in this embodiment, since the light-emitting surface 414 is a concave curved surface, the divergence angle of the light 312 when it emerges from the light-emitting surface 414 is greater than the divergence angle of the white light 122a in the prior art when it is emitted from the light-emitting surface 214 (plane). Therefore, the lens structure 400 of this embodiment can improve the light diffusion effect, so that the light energy distribution of the light 312 provided by the light emitting unit 300 is more uniform. When the light-emitting unit 300 is applied to a backlight module, it can avoid obvious light shifts in some areas of the diffuser plate.
[0056] Fig. 4 is a schematic diagram of a light-emitting unit according to another embodiment of the present invention. Referring to FIG. 4, the difference between the light-emitting unit 300a of this embodiment and the light-emitting unit 300 of FIG. 3 lies in the lens structure. Specifically, in the lens structure 400a of the light-emitting unit 300a of this embodiment, the light-emitting surface 414a of the lens body 410a is a flat surface. In addition, the lens structure 400a further includes a micro-diffusion particle layer 430 disposed on the light-emitting surface 414a. The micro-diffusion particle layer 430 has a plurality of micro-diffusion particles 432, and the particle size of the micro-diffusion particles 432 is between 1 micrometer (micrometer) and 30 micrometers. The micro diffusion particles 432 have low dispersion characteristics, and the distribution density of the micro diffusion particles 432 is, for example, similar to the distribution density of the micro diffusion particles in the diffusion plate.
[0057] The light 312 emitted from the light emitting surface 414a will be refracted and reflected multiple times between the micro diffusion particles 432, so the micro diffusion particle layer 430 can diffuse the light 312. Therefore, the lens structure 400a of this embodiment can improve the light diffusion effect, so that the light energy distribution of the light 312 provided by the light-emitting unit 300a is more uniform. In addition, in this embodiment, since the light-emitting diode light source module 310 includes red light-emitting diodes, blue light-emitting diodes, and green light-emitting diodes, the light 312 can be refracted and reflected multiple times between the micro diffusion particles 432 to make the light The light mixing of 312 is more uniform. In this way, the dispersion phenomenon caused by the material of the lens body 410a can be avoided.
[0058] It is worth mentioning that, in order to further improve the light diffusion effect, the micro-diffusion particle layer 430 may be coated on the light-emitting surface 414 of the lens body 410 of FIG. 3 (as shown in FIG. 5). In addition, the micro-diffusion particle layer 430 can also be coated on the reflective surface 416 of the lens body 410, 410a (as shown in FIGS. 6A and 6B). If the lens body 410, 410a has a reflective surface 416. If the reflective surface 416 is coated with a reflective material layer 420 (as shown in FIGS. 3 and 4), the micro-diffusion particle layer 430 can be coated on the reflective material layer 420. In addition, the micro-diffusion particle layer 430 may also be disposed on the light incident surface 412 of the lens body 410, 410a, and located in the lens body 410, 410a (as shown in FIGS. 7A and 7B).
[0059] In order to further enhance the light diffusion effect, the light incident surface 412 of the lens body 410, 410a of the lens structure 400, 400a (as shown in FIGS. 3 and 4) may also be a concave curved surface (as shown in FIGS. 8A and 8B) to Make the light diffuse.
[0060] In summary, the present invention has at least the following advantages:
[0061] 1. In one embodiment, since the light-emitting surface of the lens body is a concave curved surface, the divergence angle of the light emitted from the light-emitting surface can be increased to improve the light diffusion effect. Therefore, the light-emitting unit and the lens structure of the present invention have a good light diffusion effect.
[0062] 2. In another embodiment, the micro-diffusion particle layer on the light-emitting surface of the lens body can cause light to be refracted and reflected multiple times in the micro-diffusion particle layer, so it can not only improve the light diffusion effect of the lens structure, but also Avoid dispersion phenomenon. Therefore, the light-emitting unit using this lens structure has a good light diffusion effect.
[0063] 3. Providing a layer of micro-diffusion particles on the reflective surface and/or light-emitting surface of the lens body can further improve the light diffusion effect of the lens structure.
[0064] 4. Designing the light incident surface of the lens body into a concave curved surface can further improve the light diffusion effect of the lens structure.
[0065] Of course, the present invention can also have various other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding All changes and deformations shall belong to the protection scope of the appended claims of the present invention.
