Contact lens and detection method

A detection method comprising:

• emitting light toward tears accumulated in one or a plurality of structure portions in a contact lens that includes a lens section attachable to an eyeball, and the one or plurality of structure portions provided in the lens section and intended to accumulate tears, wherein the one or plurality of structure portions includes an inlet coupled with an inflow path and an outlet coupled with a discharge path, and the inlet is adjacent to an outer edge of the lens and the outlet is provided in an area between a pupil and an iris;
• and
• detecting, through the tears accumulated in the one or plurality of structure portions, transmitted light transmitted by the contact lens, reflected light reflected by the contact lens, diffracted-transmitted light diffracted and transmitted by the contact lens, or diffracted-reflected light diffracted and reflected by the contact lens, of the light emitted toward the tears accumulated in the one or plurality of structure portions.