Tunable optical retarders made of liquid crystal material can be built with excellent spatial and angular response. These elements have been used to construct birefringent filters which are electronically tunable. Initial breadboard systems realize passbands similar to interference filters, and filters are planned with sub-Angstrom passband. Any desired wavelength in the tuning range may be selected in a random-access fashion, in a few milliseconds. One of these filters has been successfully used recently to image the solar photosphere in the 1.2 - 1.6 micron range at the McMath solar telescope at Kitt Peak.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.