Edge coupler testing device and method, and test array

An edge coupler test device, arranged on a photonic integrated circuit, comprising:

• a loopback structure, arranged on the photonic integrated circuit, and configured to couple with an external optical fiber array;
• a cascaded test structure, arranged on the photonic integrated circuit, and configured to test an on-chip mode field conversion loss of both a TE polarized light and a TM polarized light;
• a polarization splitting module, connected to the cascaded test structure, and configured to couple the TE polarized light and the TM polarized light respectively into the cascaded test structure for a test and couple them out respectively;
• a TE grating coupling module, connected to both an input end and an output end of the polarization splitting module, and configured to couple the TE polarized light into the cascaded test structure for a test and couple it out;
• a TM grating coupling module, connected to both the input end and the output end of the polarization splitting module, and configured to couple the TM polarized light into the cascaded test structure for a test and couple it out;
• and
• a calibration structure, configured to acquire a calibration data of both the TE polarized light and the TM polarized light.