Optical phased arrays including member to correct phase error generated in manufacturing processes and method of correcting phase using the same
Provided is an optical phased array including a light injector, a first splitter connected to the light injector, a first phase shifter connected to the first splitter, a plurality of waveguides connected to the first splitter, portions of the plurality of waveguides being connected to the first splitter via the first phase shifter, an antenna array connected to the plurality of waveguides, a single mode filter provided in each of the plurality of waveguides, and a first photodetector connected to the first splitter and configured to detect a portion of light radiated onto the antenna array.
1. A method of correcting an optical phased array phase error, the method comprising:
radiating light to an antenna array of an optical phased array from outside the optical phased array;
measuring an electrical signal corresponding to at least a portion of radiated light at a first position which is provided at a first distance along a waveguide from the antenna array;
obtaining a phase correction value based on the measured electrical signal; and
applying the obtained phase correction value to the optical phased array,
wherein the measuring of the electrical signal comprises measuring an electrical signal corresponding to light deviating from a channel provided at the first position based on a phase difference between two adjacent waveguides through which the radiated light is transmitted.
2. The method of claim 1 , wherein the measuring of the electrical signal is simultaneously performed with respect to a plurality of waveguides included in the optical phased array.
3. The method of claim 1 , wherein the measuring of the electrical signal comprises measuring an electrical signal emitted from a photodetector provided at the first position and configured to receive at least a portion of the light.
4. The method of claim 1 , wherein, after phase correction is completed at the first position, when the optical phased array is normally operated, the method is repeated at a second position between a light injector into which light is injected and the first position.
5. The method of claim 4 , wherein, when measuring an electrical signal at the second position, measurements are simultaneously performed with respect to a plurality of waveguides provided between the first position and the second position.
6. The method of claim 4 , wherein, after phase correction is completed at the second position, the method is repeated at a third position between the light injector and the second position.