Patent ID: 8008620

Claim:
A substrate for mass spectrometry used in a mass spectrometry method in which a substance fixed on a surface of the substrate is irradiated with a laser beam to be ionized and to be desorbed from the surface, and the ionized substance is captured to perform mass spectrometry, the substrate comprising: a first reflective member that is semi-transmissive and semi-reflective; a transparent member; and a second reflective member that is reflective, wherein the first reflective member, the transparent member and the second reflective member are sequentially provided from the surface side of the substrate to form an optical resonator that generates resonance in the transparent member by irradiation of a surface of the first reflective member with the laser beam, and wherein the optical resonator includes, on the surface of the first reflective member, a sample separation portion at which surface interaction occurs with a plurality of analytes contained in a sample liquid.