Image pick-up lens, image pick-up device, portable terminal and digital instrument

摘要

Provided is an image pickup lens that despite being small is favorably corrected for aberrations and has a five element configuration that is wide angle and has a bright F-number also provided is an image pickup device and a portable terminal using the image pickup lens. The image surface side of the fifth lens has an aspherical shape, has an inflection point at a position other than a position that intersects with the light axis, and satisfies the following formulae: −5.0<(r1+r2)/(r1−r2)≦−1.0 (1); 0.90

主权项

1. An image pickup lens to form an image of an object onto a photoelectric conversion section, comprising, in the order from an object side thereof:
a first lens which has a positive refractive power and includes a convex surface facing the object side; a second lens which has a negative refractive power; a third lens which includes an aspheric configuration on at least one surface thereof; a fourth lens which has a positive refractive power and includes a convex surface facing an image side; and a fifth lens which has a negative refractive power and includes a biconcave configuration, wherein an image-side surface of the fifth lens includes an aspheric configuration and has an inflection point at a position other than an intersection point with an optical axis, wherein the following conditional expressions are satisfied:
−5.0<(r1+r2)/(r1−r2)≦−1.0  (1)0.90 r1 is a radius of curvature of an object side surface of the first lens, r2 is a radius of curvature of an image side surface of the first lens, f1 is a focal length of the first lens, f is a focal length of the whole system of the image pickup lens, and ΣDL13 is a distance on the optical axis from the object side surface of the first lens to the image side surface of the third lens.