In a method of producing a photomask in which a light-transmissive substrate is formed thereon with a chromium pattern having a global opening ratio difference in its plane on the light-transmissive substrate, use is made, as an etching mask for a chromium film, of an etching mask pattern made of an inorganic-based material having a resistance against etching of the chromium film. A protruding part is provided on an outer circumferential side of the hollow circular cylinder part of the fuel tank. The moving assembly includes a sliding module and at least one rotating module. As the user switches from the channel of interest to subsequent broadcast channels, the channel of interest is retained in memory as long as the amount of time spent on any subsequent channel is less than the predetermined time threshold.