Colors of the universe – market study on optical filters for professional astronomy

Ground based astronomy is an emerging field of science today. The world´s largest wide-field telescope LSST is currently being built in Chile and with the huge astronomical observatories E-ELT, TMT and GMT the next generation of extremely large telescopes is already under construction. Beyond the telescopes also the corresponding cameras and instruments are quite challenging, requiring optical components like lenses and filters in new dimensions and with new and demanding optical specifications. Such types of filters are discussed here. Classically well-defined color glass filters have been used in astronomical telescopes. Nowadays interference filters with thin-film optical coatings become more popular. These are often more expensive, but allow flexibility to create very broad or very narrow filter bands. In both cases the production of the requested large filter dimensions is demanding. Only a few specialized industrial manufacturers are able to manufacture such filters for professional astronomical telescopes. This contribution will analyze astronomer’s needs for professional filters, discuss the filter technologies, and provide a market overview on dedicated filter suppliers.