An optical pickup device comprises a light source to emit a light flux having wavelength .lamda.; an objective lens including at least two plastic lenses of a first plastic lens having positive refractive power and a second plastic lens having positive refractive power, wherein the first plastic lens and the second plastic lens are arranged in this order from the light source side; and an actuator to drive the objective lens; wherein the objective lens satisfies the following expression (1-1): -0.0004<.DELTA.3SA/(NA.sup.4f(1-m))<0.0004 (1-1) where .DELTA.3SA (.lamda.RMS) represents a rate of change of a third order spherical aberration of the objective lens when the temperature of an entire body of the objective lens uniformly changes, f (mm) represents the focal length of the objective lens for the light flux having wavelength .lamda., and m represents the magnification of the objective lens.

 
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