An aspherical lens formed of a high-refractivity low-dispersion glass, which is useful for constituting a compact and high-function image-sensing optical unit and which is formed by precision press-molding, the optical glass having a refractive index (n.sub.d) of over 1.83 and an Abbe's number (.nu..sub.d) of 40 or more and comprising, by mol %, 20 to 45% of B.sub.2O.sub.3, 5 to 24% of La.sub.2O.sub.3 and 22 to 42% of ZnO but containing no Li.sub.2O, the aspherical lens having an optical thin film formed on a surface thereof.