| 摘要 |
PROBLEM TO BE SOLVED: To provide a monofocal lens for which the entire length can be shortened in simple constitution. SOLUTION: A first lens G1 and a second lens G2 are disposed successively from an object side. For the first lens G1, a surface on the object side is planar and the surface on an image surface side is aspheric and it has refractive power relatively weaker than that of the second lens G2. For the second lens G2, at least one surface is aspheric and it is constituted of a lens having positive refractive power for which a convex surface is turned to the object side. It is desirable that the first lens G1 is constituted of optical resin. In this monofocal lens 1, since the surface on the object side of the first lens G1 is planar, in the case of using the monofocal lens 1 as the photographing lens of an electronic camera for instance, the need of surely providing cover glass on the front surface of the lens is eliminated. Also, attachment to a lens barrel is facilitated.
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