Thorlabs’ selection of dielectric-coated spectral filters is presented here. Our hard-coated bandpass filters offer higher transmission and are more durable and longer-lasting than our soft-coated bandpass filters. The high-performance edgepass filters listed here include both long- and short-pass options. Notch filters, also known as band-stop or band-rejection filters, are useful in applications where one needs to block light from a laser. We offer response-flattening filters for silicon photodiodes, an IR-blocking filter that rejects light in the MIR range, and dichroic mirrors and beamsplitters. Filter sets are available for microscopy and fluorescence imaging. We additionally offer dichroic color filters individually and as a set. Our hot and cold mirrors are ideal for use in situations where heat could severely damage an experimental setup. We also offer bandpass and edgepass filters in kits.