When melting a glass layer 3 by irradiation with laser light L1 along a region to be fused R, the glass layer 3 is irradiated with the laser light L1 having a first heat input along the region to be fused R, so as to gasify a binder and melt a glass frit 2, and the heat input is switched when the melting ratio of the glass layer 3 in a direction intersecting an advancing direction of the laser light L1 exceeds a predetermined value, so as to irradiate the glass layer 3 with the laser light L1 having a second heat input smaller than the first heat input along the region to be fused R, thereby gasifying the binder and melting the glass fit 2, thus fixing the glass layer 3 to a glass member 4.