Novel digital-tuning mechanism for lasers

Summary form only given. A wide variety of laser-tuning mechanisms exist based on analogue mechanical or thermal effects. It is important for a number of applications, including communications and spectroscopy, to have precise, repeatable, and reliable wavelength control. We present here a digital wavelength tuning mechanism, which is inherently stable, precise, and repeatable. The novel filter is based on a pixellated 2-D ferroelectric liquid crystal spatial light modulator, whose fundamental spatial periodicity (pixel dimension) is accurately defined by a photo-lithographic process.