Ocean Optics Inc. introduces linear variable filters for use in fluorescence and other spectroscopy applications. The LVF series high- and low-pass and adjustable-bandwidth filters are coated on 57 x 10 x 0.7-mm quartz substrates. They also are available as loose filters for mounting in a fixture for insertion into a cuvette holder. The adjustable-bandwidth filters block or pass light from 300 to 700 nm, and the high- and low-pass filters are combined to make variable-bandpass filters. The company says the filters' blocking capabilities (<0.2%) and resistance to heat make them suitable for spectrally shaping the excitation energy from broadband sources.