A fingerprint image pickup device includes a light source that emits a
light for transmission through a fingertip portion having a fingerprint
to be photographed, an image pickup unit that picks up the light from the
light source and transmitted through the subject to acquire a fingerprint
image in which convex and concave parts of the fingerprint are dark and
bright, respectively, and an optical system that images the light
transmitted through the fingertip portion on the image pickup unit. The
optical system is arranged so that a distal side of the fingertip portion
is tilted, at a predetermined angle, farther away from the optical system
than an opposite side, with reference to a position at which a ventral
side of the fingertip portion contacts a face orthogonal to an optical
axis of the optical system.