LIGHT GUIDE MODULE AND DISPLAY MODULE HAVING THE SAME
This application claims priority to Taiwan Application Serial Number 108123474, filed Jul. 3, 2019, which is herein incorporated by reference in its entirety. The present disclosure relates to a light guide module and a display module having the light guide module. A light guide element of a typical light guide module is adhered with a cover lens so as to protect the surface of the light guide element. However, since the fabrication of the light guide element and the cover lens cannot be integrated, the fabrication process of the light guide module has become more complicated. Moreover, for an input device with a light guide element (e.g., keyboard), the figures or textures on the button are fixed and cannot be changed. However, for a high level keyboard (e.g., keyboard for eSports), it is required to exchange the textures or figures displayed on the button based on the user setting. Therefore, there is still a developing need for an input device of which the textures or figures of the button can be exchanged arbitrarily. An aspect of the present disclosure is to provide a light guide module applied in a reflective display panel. According to some embodiments of the disclosure, a light guide element includes a first light guide layer and a light source. The light guide element includes a first light guide layer and a second light guide layer. The second light guide layer is disposed on the first light guide layer, and a refractive index of the first light guide layer is greater than a refractive index of the second light guide layer. The light source is disposed in the first light guide layer, and the first light guide layer that the light source is located is closer to the reflective display panel than the second light guide layer. In some embodiments of the disclosure, a material of the first light guide layer is Polycarbonate (PC). In some embodiments of the disclosure, a material of the second light guide layer is Polymethyl methacrylate (PMMA). In some embodiments of the disclosure, a refractive index of the first light guide layer is in a range from about 1.49 to about 1.6, and a refractive index of the second light guide layer is in a range from about 1.4 to about 1.49. In some embodiments of the disclosure, the light guide element includes a periphery area and a display area, the light guide module further includes a light blocking layer covering the periphery area of the light guide element. In some embodiments of the disclosure, the light guide module further includes housing and a light blocking layer. The housing surrounds the light guide element. The light blocking layer covers the housing. In some embodiments of the disclosure, the light guide module further includes a hard coating layer covering the light blocking layer and the light guide element. In some embodiments of the disclosure, the light guide module further includes an anti-glare layer covering the light blocking layer and the light guide element. In some embodiments of the disclosure, a surface of the first light guide layer has a microstructure. In some embodiments of the disclosure, the light guide module includes a third light guide layer disposed on a bottom surface of the first light guide layer, between the first light guide layer and the second light guide layer, or on a top surface of the second light guide layer. A refractive index of the third light guide layer is smaller than the refractive index of the first light guide layer. Another aspect of the present disclosure is to provide a display module. According to some embodiments of the disclosure, the display module includes a light guide module and a reflective display panel. The light guide module includes a light guide element and a light source. The light guide element includes a first light guide layer and a second light guide layer. The second light guide layer is disposed on the first light guide layer, and a refractive index of the first light guide layer is greater than a refractive index of the second light guide layer. The light source is disposed in the first light guide layer. The reflective display panel is located below the light guide element, and the first light guide layer that the light source is located is closer to the reflective display panel than the second light guide layer. In some embodiments of the disclosure, a material of the first light guide layer is Polycarbonate (PC). In some embodiments of the disclosure, a material of the second light guide layer is Polymethyl methacrylate (PMMA). In some embodiments of the disclosure, a refractive index of the first light guide layer is in a range from about 1.49 to about 1.6, and a refractive index of the second light guide layer is in a range from about 1.4 to about 1.49. In some embodiments of the disclosure, the light guide element includes a periphery area and a display area, the light guide module further includes a light blocking layer covering the periphery area of the light guide element. In some embodiments of the disclosure, the display module further includes housing and a light blocking layer. The housing surrounds the light guide element and the reflective display panel. The light blocking layer covers the housing. In some embodiments of the disclosure, the display module further includes a hard coating layer covering the light blocking layer and the light guide element. In some embodiments of the disclosure, the display module further includes an anti-glare layer covering the light blocking layer and the light guide element. In some embodiments of the disclosure, a surface of the first light guide layer has a microstructure. In some embodiments of the disclosure, the display module includes a third light guide layer disposed on a bottom surface of the first light guide layer, between the first light guide layer and the second light guide layer, or on a top surface of the second light guide layer. A refractive index of the third light guide layer is smaller than the refractive index of the first light guide layer. In the aforementioned embodiments, since the light source is disposed in the first light guide layer, and the refractive index of the first light guide layer is greater than the refractive index of the second light guide layer, the efficiency of light transmission and the light uniformity may be improved. The first light guide layer and the second light guide layer can be considered as an integrated structure of the typical cover lens and the light guide plate, thereby simplifying the complexity of the individual process of the typical cover lens and the light guide plate. Moreover, the reflective display panel may control the figure displayed through the input device (e.g., keyboard) in which the light guide element is applied. Therefore, the texture or figure of the button can be exchanged arbitrarily by the users. It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the invention as claimed. The disclosure can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawings as follows: Reference will now be made in detail to the present embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. Reference is made to In some embodiments, the display module 10 further includes a housing 150 and a light blocking layer 160. The housing 150 surrounds the light guide element 110 and the reflective display panel 130. In the present embodiment, the housing 150 covers the periphery area PA of the light guide element 110 and the side surface 110S. The light blocking layer 160 covers the housing 150 through spray finishing or printing. Specifically, in the present embodiment, the light blocking layer 160 covers a top surface of the housing 150 through spray finishing or printing. That is, the housing 150 and the light blocking layer 160 define the display area DA and the periphery area PA of the light guide element 110. In other words, the light blocking layer 160 overlaps the periphery area PA of the light guide element 110 in the first direction D1, but does not overlap the display area DA of the light guide element 110. As such, the housing 150 and the light blocking layer 160 can prevent the light of the light source 120 from leaking through the periphery area PA. Moreover, the light blocking layer 160 may cover the sidewall of the housing 150, thereby preventing the light of the light source 120 from laterally leaking through the housing 150. As such, since the light blocking layer 160 may provide sufficient shading ability for the light source 120, the selection flexibility for the material of the housing 150 can be increased. In some embodiments, the display module 10 further includes a system circuit 170. The system circuit 170 includes a cable 172, a circuit board 174 and an elastic contact element 176. In some embodiments, the display module 10 is a button of a keyboard or a mouse. The display module 10 displays textures or figures through the reflective display panel 130. The display module 10 controls the reflective display panel 130 through the system circuit 170. The reflective display panel 130 is electrically connected to the circuit board 174 through cable 172. The elastic contact element 176 connects the reflective display panel 130 and the circuit board 174 and can be act as a switch of the reflective display panel 130. For example, when an external force is applied on the light guide element 110 or the housing 150, the elastic contact element 176 is pushed and is electrically connected to the circuit board 174, thereby displaying the figures or erasing the figures. When the external force is removed, the elastic contact element 176 pushes the housing 150, the light guide element 110, and the reflective display panel 130 back to the original positions (the state shown in For example, for a high level keyboard (e.g., keyboard for eSports), it is required to exchange the textures or figures displayed on the button based on the user setting. Therefore, by controlling the figures displayed by the reflective display panel 130 of each of the button respectively through the system circuit 170, the textures or figures of the button can be changed arbitrarily. In some embodiments, the display module 10 further includes a hard coating layer 180. The hard coating layer 180 covers the light blocking layer 160 and the light guide element 110. Specifically, in the embodiment shown in In some embodiments, the display module 10 further includes an anti-glare layer 190. The anti-glare layer 190 covers the light blocking layer 160 and the light guide element 110. In the present embodiments, the anti-glare layer 190 is located on the hard coating layer 180. The anti-glare layer 190 can eliminate the light reflected from the surface of the light guide element 110 or the surface of the hard coating layer 180 that may disturb the eye sight of the users. In some embodiments, widths of different light guide layers may be different. In other words, the entire side surface 110S of the light guide element 110 In some embodiments, the light guide element 110 It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure cover modifications and variations of this disclosure provided they fall within the scope of the following claims. A light guide module includes a light guide element and a light source. The light guide element includes a first light guide layer and a second light guide layer. The second light guide layer is disposed on the first light guide layer. The refractive index of the first light guide layer is greater than the refractive index of the second light guide layer. The light source is disposed in the first light guide layer. 1. A light guide module applied in a reflective display panel, comprising:
a light guide element comprising a first light guide layer and a second light guide layer, wherein the second light guide layer is disposed on the first light guide layer, and a refractive index of the first light guide layer is greater than a refractive index of the second light guide layer; and a light source disposed in the first light guide layer, wherein the first light guide layer is closer to the reflective display panel than the second light guide layer. 2. The light guide module of 3. The light guide module of 4. The light guide module 5. The light guide module of a light blocking layer covering the periphery area of the light guide element. 6. The light guide module of a housing surrounding the light guide element; and a light blocking layer covering the housing. 7. The light guide module of a hard coating layer covering the light blocking layer and the light guide element. 8. The light guide module of an anti-glare layer covering the light blocking layer and the light guide element. 9. The light guide module of 10. The light guide module of a third light guide layer disposed on a bottom surface of the first light guide layer, between the first light guide layer and the second light guide layer, or on a top surface of the second light guide layer, wherein a refractive index of the third light guide layer is smaller than the refractive index of the first light guide layer. 11. A display module, comprising:
a light guide module, comprising:
a light guide element comprises a first light guide layer and a second light guide layer, wherein the second light guide layer is disposed on the first light guide layer, and a refractive index of the first light guide layer is greater than a refractive index of the second light guide layer; and a light source disposed in the first light guide layer; and a reflective display panel located below the light guide element, wherein the first light guide layer is closer to the reflective display panel than the second light guide layer. 12. The display module of 13. The display module of 14. The display module of 15. The display module of a light blocking layer covering the periphery area of the light guide element. 16. The display module of a housing surrounding the light guide element and the reflective display panel; and a light blocking layer covering the housing. 17. The display module of a hard coating layer covering the light blocking layer and the light guide element. 18. The display module of an anti-glare layer covering the light blocking layer and the light guide element. 19. The display module of 20. The display module of a third light guide layer disposed on a bottom surface of the first light guide layer, between the first light guide layer and the second light guide layer, or on a top surface of the second light guide layer, wherein a refractive index of the third light guide layer is smaller than the refractive index of the first light guide layer.CROSS-REFERENCE TO RELATED APPLICATION
BACKGROUND
Field of Invention
Description of Related Art
SUMMARY
BRIEF DESCRIPTION OF THE DRAWINGS
DETAILED DESCRIPTION






