Patent Application
20080298084
1. Field of the Disclosure
The disclosure relates to displays for mobile communication devices.
2. Introduction
As mobile communication devices become smaller and thinner, the displays on those devices must become thinner. The battery size is also limited by the compact design. Therefore, there is a demand for using thin, light-weighted and power saving displays for mobile devices.
Some conventional devices, for example, use a thin, highly reflective electro-phoretic display (EPD) that meets these requirements. However, using reflective display may be at the expense of proper illumination of the display. For example, most of the reflective displays are opaque, and cannot use a backlighting system. A front light can light up a reflective display, but the lighting system of a traditional front light is usually thick and needs an air gap between light guide and the display. An expensive anti-reflective coating is usually required to maintain the contrast. A front light guide must be transparent and free of visual artifacts. Non-transparent or scattering light guide material will decrease the amount of light ultimately reaching the center of the display, and result in a low contrast ratio.
A display for a mobile communication device is disclosed. The display may include a first layer with refractive index n1, having at least a rough surface on one side, a second layer, having refractive index n2, applied contiguously on a side opposite from the rough side of the first layer, wherein n1>n2>nair and nair is the refractive index in air media, a reflective display disposed on a side of the second layer opposite from the first layer, and at least one light source located adjacent to at least one edge or side of the first layer.
In order to describe the manner in which the above-recited and other advantages and features of the disclosure can be obtained, a more particular description of the disclosure briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the disclosure and are not therefore to be considered to be limiting of its scope, the disclosure will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:
Additional features and advantages of the disclosure will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the disclosure. The features and advantages of the disclosure may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features of the present disclosure will become more fully apparent from the following description and appended claims, or may be learned by the practice of the disclosure as set forth herein.
Various embodiments of the disclosure are discussed in detail below. While specific implementations are discussed, it should be understood that this is done for illustration purposes only. A person skilled in the relevant art will recognize that other components and configurations may be used without parting from the spirit and scope of the disclosure.
The disclosure comprises a variety of embodiments, such as a method and apparatus and other embodiments that relate to the basic concepts of the disclosure.
The following terms have the definitions as stated below:
This disclosure concerns a display for a mobile communication device that may include a very thin layer with a very high refractive index to serve as the front light which may be laminated or coated onto a reflective type of display. Also, the display may include a rough surface on top of the high refractive index layer that can bend the light towards the reflective display.
However, between the thin layer and the reflective display may be a very thin layer with low refractive index. This layer of low refractive index may be an adhesive to laminate the thin very high refractive index layer to the reflective display. The low index layer may also be coated onto one side of the high refractive index layer. In any event, the low index adhesive, coating or film work with the high index layer so that light can be guided to the center of the display through total internal reflection.
The mobile communication device 100 may be a portable MP3 player, satellite radio receiver, AM/FM radio receiver, satellite television, portable music player, portable laptop, portable computer, e-book, wireless radio, wireless telephone, portable digital video recorder, cellular telephone, mobile telephone, or personal digital assistant PDA), combinations of the above, for example.
The casing 110 may be made at any durable material synthetic or metal capable of housing components of the mobile communication device 100. The display 120 will be described below with respect to
The low refractive index layer 220 has a refractive index n2, where 1.2≦n2≦1.5 or 1.2≦n3≦1.5, for example. Note that low refractive index layer 220 may be a low index coating applied directly onto high refractive index layer 210 or an adhesive. There could also be an adhesive layer between the low refractive index layer 220 and the reflective display 230 with any index of refraction.
Once light is directed into the display 120 structure by the light source 310, high refractive index layer and the low refractive index layer work together so that light can be guided to the center of the display through total internal reflection. By combining these layers having different refractive properties, less light is dissipated and more light is present to more fully illuminate the display. Accordingly, less power may be required in order to obtain a brighter display illumination.
At step 4300, the process disposes a reflective display 230 on the side of the low refractive index layer 220 opposite the high refractive index layer 210. At step 4400, the process disposes at least one light source 310 adjacent to at least one edge of the high refractive index layer 210. The process goes to step 4400 and ends.
Although the above description may contain specific details, they should not be construed as limiting the claims in any way. Other configurations of the described embodiments of the disclosure are part of the scope of this disclosure. For example, the principles of the disclosure may be applied to each individual user where each user may individually deploy such a system. This enables each user to utilize the benefits of the disclosure even if any one of the large number of possible applications do not need the functionality described herein. It does not necessarily need to be one system used by all end users. Accordingly, the appended claims and their legal equivalents should only define the disclosure, rather than any specific examples given.
