Patent ID: 7280192
Filing Date: 2007-10-09
Classification: G01M

Abstract:
1. A lens meter for measuring optical characteristics of a subject lens to be measured, the lens meter comprising: a lens rest having an aperture of predetermined diameter, which supports the subject lens; a measurement optical system including a measurement optical axis passing through the aperture, a light source projecting a measurement light bundle along the measurement optical axis, a target plate having a plurality of measurement targets, and a two-dimensional image sensor detecting images of the targets, the target images being formed by the measurement light bundle having passed through the subject lens, the aperture, and the target plate; a calculation part which obtains refractive power distribution within a measurement region of the subject lens based on a detection result obtained by the image sensor, the measurement light bundle having passed through the measurement region being capable of passing through the aperture; a detection part which detects a position of the subject lens in a two-dimensional direction orthogonal to the measurement optical axis; guiding means for guiding movement of the subject lens on the lens rest so as to shift the measurement region so that refractive power distribution within an analysis region of the subject lens including a distance portion, a progressive portion, and a near portion is obtained; a storage part which stores the refractive power distribution within the measurement region obtained in accordance with the shift of the measurement region by the movement of the subject lens while associating with the position detected at the time of the obtainment; a display part; and a display control part which controls to display a map of the refractive power distribution within the analysis region on the display part based on the stored refractive power distribution within the measurement region and the stored position.