Use the LP580 when background suppression matters more than sheer passband width. OPTOStokes specifies 575–825 nm passband at >90%, 350–565 nm stopband at T < 0.001%, OD5 minimum attenuation, 1.0 mm thickness, and 60/40 surface quality. That is a different tool from a standard high-transmission LP filter like the LP595, which passes 600–1100 nm at >90% and blocks 350–590 nm at <1%. In real systems, LP580 fits fluorescence, confocal microscopy, flow cytometry, and imaging paths where excitation leakage will kill contrast. LP595 fits red/NIR separation when you still want a broad high-throughput passband. OPTOStokes also states that LP580 can be customized to higher OD levels up to OD7 and is available from in-stock selection for prototyping.