Moser plate

I have a glass plate in violet tone and with 3 birds on the backside. Its rather thick and with diameter 30 cm. It is in very good condition and signed Moser Karlsbad with the sign used by Moser 1911-1938.I have the books of Moser glass and even searched on internet but I have not found the same plate anythere. Has it been in Mosers production and in that case from the period 1911-1938 or is it a fake? I have seen some Hussmann plates with the same colour but not simular in other ways.