| 摘要 |
A front-illuminating device of the present invention, which is placed over the entire surface of an object to be illuminated such as a reflection-type liquid crystal display device when it is used, is provided with a light source and a light-directing body. The light-directing body has an incident surface on which light from the light source (light-source light) is made incident, a first light-releasing surface for releasing the light toward the object to be illuminated, and a second light-releasing surface which faces the first light-releasing surface and releases reflected light from the object to be illuminated. The second light-releasing surface is formed into a step shape in which slanting portions and flat portions are alternately placed. The light source light, released from the first light-releasing surface to the object to be illuminated, is reflected by the object to be illuminated and the reflected light is allowed to reach the observer from the first light-releasing surface through the flat portions. In this case, among the light-source light rays, the light components progressing in parallel with the flat portions are reflected by the slanting portions and directed to the object to be illuminated. Consequently, the present invention makes it possible to provide a brighter front-illuminating device in which the efficiency of use of the light-source light is improved.
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