| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an LED lighting device capable of securing a superior light distribution and moreover making its thickness thinner. <P>SOLUTION: The light guide 4 includes a reflection surface having as a cross-sectional line 7 a group of curved lines formed by drawing down projection lines 9 of an arbitral angle toward the light guide 4 from a position 2 separated by a prescribed distance from a central point of an LED element 2 on the cross-sectional line 7a of a virtual reflection surface wherein a suitable light distribution can be obtained and making cross the same to divide the cross-sectional line 7a; by similarly expanding and reducing, out of the divided lines, a divided line which is not settled between lines of thickness enough to make entire incident light incident so as to be settled between the lines of the thickness; and by making a connection between the divided lines which are similarly expanded or reduced by connection lines of the same or smaller angle than the projection line which passes through the connection point. <P>COPYRIGHT: (C)2012,JPO&INPIT |
