Интерференционный фильтр диаметром 240 мм на 555 нм

This is a very large diameter interference filter which appears to have a peak bandpass around 555 nm. The glass is 240mm in diameter, and 8mm thick, polished both sides. There is a marking in ink on the periphery that states BP = 14-2483. There are also four indications 90 degrees apart – V I, II V, III V, and IV V. Additionally, in pencil is the number 937-5.