Colored Glass Replacement Longpass Filters feature dielectric coatings that provide wide reflection and transmission bands with steep transition slopes. Unlike colored glass filters that block undesired wavelengths via absorption, these filters provide blocking via reflection, making their performance independent of thickness. These filters are constructed from 100% environmentally safe, RoHS compliant materials, and their manufacturing process enables custom options not available in colored glass including customer-specified cut-on wavelengths and larger dimensions. Colored Glass Replacement Longpass Filters are ideal for environmental monitoring, immuno-diagnostic testing, DNA analysis, and applications requiring RoHS compliant materials. A wide operating temperature range of -100 to +400°C also enables use in harsh environment conditions.