IMAGE TAKING LENS, IMAGE TAKING DEVICE, AND PORTABLE TERMINAL

摘要

Disclosed is an image taking lens most suitable for mass production and compaction and enabling minimization of the defocus attributed to the variation of the refractive index of a resin lens due to a temperature increase and attributed to the variation of the shape of the lens surface. The image taking lens includes one or more lens blocks each of which is provided with lens sections formed on either the object-side surface and/or the image-side surface of a lens substrate which is a parallel plate and having a positive or negative power, in each of which either the refractive index and/or the Abbe number of the lens sections is different from that of the lens substrate, and in each of which the lens sections are formed on both surfaces of the lens substrate. The taking lens is characterized in that when the lens block disposed nearest to the object side is a first lens block and when the lens section formed on the object side of the first lens block is a 1a-th lens, the 1a-th lens has a positive refractive power and satisfies the following expression. -9×10-5/°C = dn/dT(1) = -2×10-5/°C where dn/dT (1) is the temperature variation coefficient of the refractive index of the material which the 1a-th lens is formed of.