A lens meter for measuring optical characteristics of a lens to be
measured includes a measurement optical system including a light source
which projects a measurement light beam to the lens and a light receiving
sensor which receives the measurement light beam having passed through
the lens; an arithmetic part which obtains optical characteristic
distribution of a predetermined measurement region of the lens based on a
light reception result of the light receiving sensor; near-vision-portion
determination means which determines whether a near vision portion of the
lens is present in the measurement region based on the optical
characteristic distribution in the measurement region; and detection
means which detects presence of a non-optical region in addition to an
optical region of the lens in the measurement region based on the light
reception result of the light receiving sensor; the arithmetic part
obtains additional power of the lens based on the optical characteristic
distribution of the optical region in the measurement region when the
near-vision-portion determination means does not determine the presence
of the near vision portion in the measurement region and the detection
means detects the presence of the non-optical region in the measurement
region.