Patent ID: 7764364

Claim:
A lens meter for measuring optical characteristics of a target lens to be measured, comprising: a measurement optical system including a light source which projects a measurement light beam to the target lens, a target plate having a plurality of targets, and a light receiving sensor which receives the measurement light beam having passed through the target lens and the target plate, the measurement optical system being configured to simultaneously measure a distribution of the optical characteristics at a plurality of measurement positions within a predetermined measurement region of the target lens; an arithmetic part which obtains the distribution of the optical characteristics at the measurement positions within the measurement region of the target lens based on a received result by the light receiving sensor; mode selecting means which selects between a single focal lens measurement mode and a progressive lens measurement mode; detecting means which detects a direction and a degree of displacement of a current measurement position in a vertical direction from a near vision portion of a progressive lens which is the target lens based on additional power, spherical equivalent power, or spherical power in the distribution of the optical characteristics at the measurement positions within the measurement region and detects a direction and a degree of displacement of the current measurement position in a lateral direction from the near vision portion of the progressive lens based on cylindrical power in the distribution of the optical characteristics at the measurement positions within the measurement region, when the progressive lens measurement mode is selected and alignment is made to bring the measurement position into the near vision portion; a display which displays an alignment screen; and a display control part which causes the display, based on a detection result by the detection means, to display a first guide mark indicating a direction in which and an amount by which the progressive lens must be moved based on the direction and the degree of displacement in the vertical and lateral directions to bring the measurement position into the near vision portion.