Glossary of terms for Filters - Omega Optical, a company specializing in optical interference filters, sponsors this web-dictionary containing definitions of many useful terms associated with optics and filters.
MicroWorld Glossary - The Glossary of Microscopy and Microanalytical Terms contains introductory information on techniques and instruments used by microscopists.
Photonics Dictionary - Sponsored by the magazine Photonics Spectra, this searchable reference of optical terminology is a valuable research tool for students and scientists in the fields of optics, light, and color.
Standard Terminology of Microscopy - Provided by the University of Minnesota, this very large glossary of microscopy-related terms is an excellent resource for advanced terminology and information.
Technical Instrument San Francisco - Compiled by TISF, a Northern California Nikon microscope distributor, this website contains a detailed glossary of terms utilized in optical microscopy and several tutorials on microscopy, contrast enhancement, and digital imaging.