Optical modulating device

An optical modulating device, comprising:

• an optical splitter which is used to receive an inputting optical signal and split the inputting optical signal by an optical splitting ratio to generate a first split optical signal and a second split optical signal;
• an optical phase modulator which couples the optical splitter to receive the first split optical signal and the second split optical signal and phase modulate the first split optical signal and the second split optical signal to respectively generate a first modulating optical signal and a second modulating optical signal;
• and
• an optical combiner which couples the optical phase modulator to receive the first modulating optical signal and the second modulating optical signal and combine the first modulating optical signal and the second modulating optical signal by a combining ratio to generate an outputting optical signal having a desired chirp, the combining ratio being equal to the optical splitting ratio as a predetermined value,
• wherein the predetermined value is configured to make the outputting optical signal have a max optical modulation amplitude at the desired chirp.