Jig and calibration method

A jig, configured to calibrate a light transceiver module and comprising:

• a disposition region for the light transceiver module, wherein the light transceiver module is suitable to be disposed on the disposition region for the light transceiver module;
• and
• an arc structure, taking a position of the disposition region for the light transceiver module as a circle center thereof and comprising:
• a plurality of reflective regions;
• a plurality of light-absorbing regions, wherein the reflective regions and the light-absorbing regions are alternately arranged;
• and
• a feature region, being a region for reflection or a region for absorbing light, wherein when the feature region is the region for reflection, a width of the region for reflection is different from a width of each of the reflective regions, and when the feature region is the region for absorbing light, a width of the region for absorbing light is different from a width of each of the light-absorbing regions.