Optoelectronic modulator

Claim 1

An optoelectric modulator for generating an optical signal comprising a wafer of optoelectronic material, two spaced lightwave conductors having opposite ends at which they are connected to each other to form input and output ends, means for introducing a lightwave of constant amplitude and wave length at said input end, the lightwave undergoing division in the conductors and mutual phase shift, the conductors being uncoupled between the input and output ends so that the divided lightwaves in the conductors do not influence one another, a difference modulation between the conductors being sensed at the output end, and three planar electrodes extending substantially parallel to one another and respectively including transversely offset portions such that two adjacent electrodes define with their longitudinal sides an elongate intermediate space of up to three sections, which are transversely displaced in relation to each other such that one longitudinal side of one of the sections is situated approximately in the line of extension of the other longitudinal side in the adjacent section, the lightwave conductors being disposed along said extension lines so as to be connected with one portion of one electrode and an adjacent portion of the adjacent electrode, means for applying a modulating voltage between the middle electrode and the two outer electrodes, so that the lightwave conductors are modulated in counter-phase in the two adjacent sections by said modulating voltage, the relationship between the lengths of said sections being such that the ratio of the length of the longest section and the length of the electrodes is in the range of 0.70 to 0.94 whereby the modulator has a frequency response between DC and high frequencies.