Linear waveguide modulator capable of optical power modulation by more than 50%

A theoretical investigation is reported of different variants of a modulator based on coupled waveguides with a Y coupler at the entry. A calculation is made of the parameters of three-section modulators (two rows of electrodes of identical length separated by an electrode-free region) ensuring that the third-order intermodulation noise does not exceed –100 and – 60 dB in the range of the modulation depths of the output optical signal of at least up to 50 and 80%, respectively. A method is proposed for the compensation of technological errors contributing to the coupling constant of the waveguides. This method should make it easier to construct the investigated modulator structures.