Glue to match but become from two slices of glasses of red and green.It and in colorful movie positive slice manufacturing and use the safe glass that dark room illuminate, it is before putting in the floodlight, on the other hand to colorful positive the slice does not produce to exposed to light the function, certainlying have at the same time bright degree, to give the dark room to operate convenient condition of the creation necessity.The spectrum curve sees the diagram.