Patent ID: 7614744

Claim:
An optical image measuring apparatus for forming an image of the object to be measured based on a received interference signal, comprising: an illumination optical system for illuminating an object to be measured with observation light; observation light receiving means for receiving reflection light of the observation light on the object to be measured to generate a signal; observation light focusing means for focusing the reflection light of the observation light on the observation light receiving means; display means for displaying an observation image of the object to be measured based on a signal generated by the observation light focusing means; operating means operated to start image measurement based on the observation image; a measurement light source for generating measurement light when the operating means is operated; dividing means for dividing the generated measurement light into signal light propagating through the object to be measured and reference light propagating through a reference object; superimposing means for superimposing the signal light propagating through the object to be measured and the reference light propagating through the reference object on each other to produce interference light; measurement light receiving means for receiving the produced interference light to generate a signal, provided to locate a measurement object point in a position shifted from a position of the observation object point in the optical path direction of the signal light by a predetermined distance when the reflection light of the observation light is focused on the observation light receiving means; and optical path length adjusting means for adjusting an optical path length difference between the signal light and the reference light to shift the measurement object point of the measurement light receiving means to a position of the observation object point shifted by the predetermined distance when the operating means is operated, wherein the observation object point is a focus point where the reflective light of the observation light is focused on the observation light receiving means, and wherein the measurement object point is a point that forms an image point of the interference light on the measurement light receiving means.