A testing or sampling probe to determine the response of electrical circuits or devices to ultrafast electrical pulses. The probe is detachable from the device being tested. The probe includes a transparent substrate though which optical pulses are focused or directed onto a photoconducting gap. The...http://www.google.es/patents/US4851767?utm_source=gb-gplus-sharePatente US4851767 - Detachable high-speed opto-electronic sampling probe
