Disclosed is a method for producing a polyphenylene ether, which comprises a step of preparing a polymerization solution composed of 10-25 parts by mass of a phenolic compound and 75-90 parts by mass of an aromatic solvent with the total of the compound and the solvent being 100 parts by mass, and 0. The alarm tag further includes a second input unit for generating signals for arming the alarm tag and triggering an alarm, and an independent auxiliary input unit that generates independent signals that arm the alarm tag and trigger an alarm. Though being small in information amount, this approximation information makes it possible to calculate distortion aberration under every shooting condition. Further, with an auxiliary plate disposed on an upper surface of the curable synthetic resin film, it is possible to manufacture a radiation detector free from warpage and cracking due to temperature change.