Microwave frequency range electro-optic modulator with efficient input coupling and smooth wideband frequency response

An electro-optic modulator assembly comprising:

• a travelling-wave electro-optic modulator having an optical input, an optical output, and an electrical modulation electrode means having a predetermined input impedance, said modulation electrode means including a coplanar waveguide;
• input connector means for receiving an electrical modulation input signal, having a predetermined output impedance which is different from said predetermined input impedance, said input connector means including a microstrip line;
• microwave energy absorbing means positioned to absorb spurious resonant microwave emissions from said electro-optic modulator;
• and
• Chebyshev impedance matching transformer means for coupling the input signal from the input connector means to the modulation electrode means, and matching said output impedance to said input impedance respectively, wherein the impedance matching transformer means comprises a tapered coplanar waveguide transformer and wherein the modulation electrode means is constructed to operate at microwave input signal frequencies, the impedance matching transformer means matching said output impedance to said input impedance at said microwave input signal frequencies.