Patent ID: 6384590
Filing Date: 2002-05-07
Classification: G01R

Abstract:
A light receiving circuit for use in electro-optic sampling oscilloscope which receives first and second optical signals resulting from polarized separation of an optical signal whose polarized state reflects the voltage of a signal to be measured, and which produces an electric signal corresponding to the relative relationship between the intensity of the first optical signal and the intensity of the second optical signal, said circuit comprising:first and second photo-electric conversion elements which are connected in series between a first bias power supply and a second bias power supply, receive the first and second optical signals, and respectively, for converting the first and second optical signals into electric signals; an amplifier which receives an electric signal appearing in a point of connection between the first and second photo-electric conversion elements for amplifying the electric signal; a first detector for detecting the electric signal converted by said first photo-electric conversion element wherein the first detector is connected in series between the first bias power supply and the first photo-electric conversion element; and a second detector for detecting the electrical signal converted by said second photo-electric conversion element wherein the second detector is connected in series between the second bias power supply and the second photo-electric conversion element.