Patent ID: 6788401
Filing Date: 2004-09-07
Classification: G01M

Abstract:
A lens inspection apparatus for inspecting a lens in order to evaluate the resolution of the lens by projecting image light containing a test pattern for resolution measurement onto a screen through the lens, and displaying an image of the test pattern for resolution measurement on the screen, comprising:an inspection sheet having the test pattern for resolution measurement; an inspection-sheet holder that holds the inspection sheet; a light source that introduces a light beam to the test pattern of the inspection sheet held by the inspection-sheet holder; and an image-light detecting section having an image pickup device that captures an image projected on the screen through the inspection sheet, and the test pattern including a measuring region in which linear light-shielding portions are arranged in stripes in order for transmitted light to have a predetermined spatial frequency, the inspection-sheet holder including a holder body having an opening forming a light-transmissive section corresponding to the test pattern of the inspection sheet that positions the inspection sheet at a focal position of the lens, the inspection-sheet holder including a rotary holding portion having a light-transmissive portion, and the rotary holding portion holding the inspection sheet so that the inspection sheet rotates in a plane relative to the holder body.