Patent ID: 8427926

Claim:
An optical pickup lens comprising: a first surface on which a light beam from a laser light source is made incident; and a second surface opposed to an optical disc positioned at an opposite side against the first surface, the optical disc including an optical disc substrate and a light transmitting layer in the optical disc, wherein the optical pickup lens focuses the light beam having a wavelength of 410 nm or shorter from the laser light source onto the optical disc without passing through any diffraction ring zone, the optical pickup lens is a single lens in which: a numerical aperture NA is equal to or larger than 0.84; a curvature radius r 1 of the first surface is 0.7679574≦r 1 ≦1.115539 mm; and a refractive index n for 405 nm wavelength is 1.52≦n≦1.5899, and the second surface has a convex aspherical shape on an optical disc side, having radii h 1 , h 2 , and h 3 from an optical axis to a lens periphery side, where h 1 <h 2 <h 3 , and sags at the radii h 1 , h 2 , and h 3 , wherein the sags at the radii h 1 , h 2 , and h 3 are sag 1 , sag 2 , and sag 3 , respectively, and differentials in the sag 1 , sag 2 , and sag 3 are Δsag 1 , Δsag 2 , and Δsag 3 , respectively, where 0>Δsag 1 >Δsag 2 and Δsag 2 <Δsag 3 .