Optical filters have many functions, including color correction, used to improve color balance in many optical systems, to neutral density filters that produce specific reduction in the level of transmitted light. The characterization of these diverse optical filter types is critical from design through manufacturing, providing validation of a specific design and the necessary means to perform QC/QA of finished products. This application note highlights PerkinElmer® LAMBDA™ 1050 for determining the best method for the analysis of specific optical filters.