Abstract: An optical phase characteristic measuring apparatus includes a harmonic generator for generating a harmonic wave from a fundamental wave of output light from a light source; a beam splitter for splitting a fundamental-wave component of the output light and a harmonic component; a sample disposed in one of optical paths along which light beams from the beam splitter propagate; a unit that is composed of a signal generator and a mirror and is adapted to modulate the length of one of the optical paths; an optical mixer for mixing the light beams containing the fundamental-wave component and the harmonic component; an optical separator for separating light output from the optical mixer into a fundamental-wave component and a harmonic component; a first optical detector for detecting a fundamental-wave component of an output from the optical separator; a second optical detector for detecting a harmonic component of the output from the optical separator; and a phase detector for detecting the phase difference betwe

Abstract: In an optical pulse characteristic measuring apparatus, optical pulses to be measured are introduced at the incident end, and split at an beam splitter. A first resultant light beam is reflected by a mirror as a local oscillation light of homodyne detection and is adjusted in a delay element so as to have the same optical path length as that of the second resultant light beam. Subsequently, the first light beam is led to an optical mixer. The second light beam is reflected by a mirror, which is controlled by a signal from a signal generator for modulation of optical path length difference. The second light beam is then reflected by a delay element and is led to the optical mixer. The two light beams combined at the optical mixer are detected by optical detectors. The AC signal component generated by modulation of the optical path length difference is amplified up to a measurable voltage by a differential amplifier.