An optical image measuring instrument capable of shorting the measurement time. A flash is outputted from a xenon lamp (2) and converted into a wide-band light by means of an optical filter (2A). The flash is converted into a linearly polarized light by means of a polarizing plate (3). The linearly polarized light is divided into a signal light (S) and a reference light (R) by means of a semitransparent mirror (6). The reference light (R) is converted into a circularly polarized light by means of a wavelength plate (7). The signal light (S) and the reference light (R) are combined by means of a semitransparent mirror (6) to produce an interference light (L). A CCD (23) detects the interference light having the same characteristic as the interference light (L). The interference light (L) is separated into an S-polarized component (L1) and a P-polarized component (L2) by means of a polarized beam splitter (11). These components are detected by means of CCDs (21, 22). A computer (30) creates an image of an object (O) to be measured from the detection signals from the CCds (21, 22, 23). Wit such an optical image measuring instrument (1), since two polarized components (L1, L2) of the interference light (L) can be simultaneously obtained, the measurement time can be shortened.
