Abstract: An electro-optic sampler utilizes a Pockels cell comprising an electro-optic crystal and a separate, removable sample carrier having an electrical transmission line affixed thereto to provide an electric field accessible to the optical sampling pulses. In the present system, a device under test is bonded to the removable sample carrier. The electro-optic crystal is not bonded to the carrier. Rather, means are provided for the electro-optic crystal to releasably engage the sample carrier and its affixed electrical transmission lines. Upon completion of a test, the carrier may be removed from the system with the device-under-test affixed thereto, and the same electro-optic crystal may be utilized in conjunction with another removable sample carrier having another device under test affixed thereto.

Abstract: In a single mode fiber under test a direct measurement of transmissive dispersion, such as of colors or polarizations, is produced. In the measurement of chromatic dispersion, light is modulated in amplitude by a first, high frequency signal and between one wavelength and another by a second, low frequency signal. Light transmitted through a fiber under test is received by a photodetector providing an output which is compared to the high frequency reference for phase by a first phase-sensitive detector. The amplitude modulated output of the first phase-sensitive detector is compared by a second phase-sensitive detector, preferably a lock-in amplifier to the low frequency reference signal to provide a signal indicative of transmissive dispersion. Other forms of dispersion, including polarization dispersion, may be measured. A source is modulated at a first, high frequency.