LANNION, France, Jan. 24, 2012 — Yenista Optics has released an ultrafine option for its flattop optical tunable filters, the XTM-50 and XTA-50. This option reduces the minimum bandwidth to 32 pm, or 4 GHz at 1550 nm. In the development of next-generation 100-Gb/s transmission systems, the need for extremely narrow tunable filters has emerged to investigate new modulation formats and their subbands. The ultrafine option meets this requirement by providing a higher selectivity to its XT range of filters. It offers bandwidth adjustability from 32 pm (4 GHz) to 650 pm (80 GHz), and edges of 800 dB/nm. In the standard version, these values are of 50 to 800 pm and 500 dB/nm, respectively. The filters operate in the 1480- to 1620-nm-wavelength range and have very low dispersion and loss characteristics. Designed for demanding applications, the company said they will meet the needs of engineers developing new transmission technologies and modulation formats, such as orthogonal frequency division multiplexing.