紅外線

Red; popular; revolutionary; bonus; surname; used in 'women's work' (sewing, embroidery); refers to profit or a gift.

Outside; external; foreign; in addition; not belonging to a certain scope; referring to relatives on the mother's or wife's side; a role in traditional opera playing an elderly man.

Thread; string; wire; line; a thin, flexible object; a route or path; a boundary or limit; a clue.