| 摘要 |
<P>PROBLEM TO BE SOLVED: To radiate the light emitted from a light emitting diode, to the external at an arbitrary angle smaller than 90° which is measured from the normal direction of the viewer-side surface of the light emitting diode. <P>SOLUTION: A luminous portion 12 of a light emitting diode 11 is so subjected to covering as to radiate the light generated from the luminous portion 12, to the external through a cap portion 14 formed out of a transparent material. Then, a cone-form recessed portion 15 is so formed in the cap portion 14 as to form an inclined boundary surface 16 for refracting at a specific angle smaller than 90° which is measured from the normal direction of the viewer-side surface of the light emitting diode 11 the light radiated from the luminous portion 12 to this cone-form recessed portion 15. Thus, the incident angle of the light arriving directly at the cone-form recessed portion 15 from the light emitting diode 11 is so increased in the scope not larger than a critical angle as to be able to radiate efficiently to the external the light having a large incident angle smaller than 90° which is measured from the normal direction of the viewer-side surface of the light emitting diode 11. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
