| 摘要 |
The invention provides a photographic lens which uses a low-hygroscopicity resin lens component as a constitutional component, is made compact without incurring some expense, and enables the optical properties to be kept stable to an atmospheric humidity change. The photographic lens is of the single-focus or varifocallength type that comprises a plurality of lens components among which at least one or more lens components are resin lens components, wherein at least one of the resin lens components is formed of a low-hygroscopicity resin. For instance, the invention is applicable to a single-focus lens comprising four lens components, i.e., a positive meniscus lens component convex on the object side, a double-concave lens component, a double-convex lens component and a negative meniscus lens component convex on the image surface side. If a polyolefin type resin that is a low-hygroscopicity resin is used for the fourth lens component of this single-focus lens, it is then possible to obtain a single-focus lens which is of small size, inexpensive and stable in optical properties to an atmospheric humidity change.
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