Contactless optical probing of edge-coupled photonic ICs

A photonic integrated circuit (PIC) testing apparatus, comprising:

• a prober to be positioned relative to a plane of a PIC device under test (DUT);
• and
• an optical probe, wherein:
• a base of the optical probe is attached to the prober;
• and
• an out-of-plane edge coupler (EC) is proximal to a free end of the optical probe, wherein the out-of-plane EC comprises a mirror or lens to redirect light between a first propagation within the optical probe and a second propagation within the plane of the PIC DUT.

A photonic integrated circuit (PIC) testing apparatus, comprising:

• a prober to be positioned relative to a plane of a PIC device under test (DUT);
• and
• an optical probe, wherein:
• a base of the optical probe is attached to the prober;
• an out-of-plane edge coupler (EC) is proximal to a free end of the optical probe;
• the optical probe extends out of a plane of the prober to intersect the plane of a PIC DUT when the plane of the prober is substantially parallel the plane of the PIC DUT;
• and
• the out-of-plane EC is to couple light propagating within a free space gap between the free end of the optical probe and a PIC-to-fiber EC of a photonic waveguide in the PIC DUT.

A method of testing a photonic integrated circuit (PIC), the method comprising:

• positioning a prober relative to a PIC device under test (DUT), wherein the prober comprises an optical probe, and the optical probe comprises an out-of-plane edge coupler (EC) proximal to a free end of the optical probe, wherein the out-of-plane EC comprises a mirror or lens to redirect light between a first propagation within the optical probe and a second propagation within a plane of the PIC DUT;
• positioning the free end of the optical probe within a trench in the PIC DUT to a depth that aligns the out-of-plane EC with a photonic waveguide of the PIC DUT comprising a PIC-to-fiber EC;
• and
• conveying optical signals between the optical probe and the photonic waveguide.