| 摘要 |
<p>PURPOSE:To improve the light emission efficiency, to reduce an irregularity in illuminance, and to make the illuminance constant by arraying light source bodies in the length direction of a printed board by forming a Fresnel lens which converges luminous flux only in a direction crossing the length direction of the printed board at right angles on the light emission surfaces of the light source bodies. CONSTITUTION:The light source body 15 consists of a reflection case 12 where a light emitting element 10 and a lead frame 11 are put and a transparent resin body 14 which has the light emitting element 10 sealed in the reflection case 12 with transparent resin 13. Plural light source bodies 15 are arrayed on the printed board 16 in its length direction X and the light emission surface 17 of each light source body 15 is formed in a Fresnel lens shape which has plural projection parts 18 so as to converge luminous flux only in the direction Y intersecting the length direction X of the printed board at right angles as to the projection light from the light emitting element 10. Consequently, the projection light can be converged while prevented from being scattered by the projection parts 18 to improve the light emission efficiency, and the illuminance is reduced and made constant.</p> |
