| 摘要 |
<p>[Problem] To provide an image pickup lens, which is a high-speed lens and achieves high resolution even at peripheral field angles, while reducing the total length. [Solution] A first lens (L1) having a negative refractive power, a second lens (L2) having a positive refractive power, a third lens (L3) having a negative refractive power, a fourth lens (L4) having a positive refractive power, and a fifth lens (L5) having a negative refractive power are disposed in this order from the object side. The image-side surface (S11) of the fifth lens (L5) is aspheric with one or more inflection points, and has a concave shape on the image side in a paraxial region. When R2 represents the curvature radius of the image-side surface (S2) of the first lens (L1), R4 represents the curvature radius of the image-side surface (S4) of the second lens (L2), and f4 represents the focal point distance of the fourth lens (L4), the conditional formulae of (1a): -1.5<f/R2<1.6, (2a): -1.6<f/R4<0.05, and (3a): 0.95 =f4/f=4.3 are satisfied at the same time.</p> |
