| 摘要 |
A Fresnel lens (5) is provided. The Fresnel lens (5) includes a plurality of prisms (7) arrayed on an incident surface side thereof, the prisms refracting light incident on a refractive surface (7a), and reflecting the light refracted thereon on the reflective surface (7b) to be directed to an exit surface side (7c), in which at least a part of the Fresnel lens (5) includes a space-adjusting surface (7d) provided to separate base portions of the refractive surface (7a) and the reflective surface (7b) between adjacent prisms.
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