| 摘要 |
A Fresnel lens, flash module and apparatus for digital picturing image comprising the same are provided to obtain the maximal luminance characteristic and the excellent brightness uniformity. The first-fourth concave parts(131a,131b,131c,131d) are formed in the Fresnel lens(131). Each concave part has a different curvature. The concave part is formed longer than in the Fresnel lens. The second concave part arranged in the outside of the first concave part has the curvature which is greater than the first concave part. The third concave part arranged in the outside of the second concave part has the curvature which is greater than the second concave part. The fourth concave part arranged in the outside of the third concave part has the curvature which is greater than the third concave part.
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