Patent ID: 7809272
Filing Date: 2010-10-05
Classification: G02B,H04J

Abstract:
1. A tunable filter for use in an optical communications network, comprising: a pair of gratings; a pair of transform lenses; wherein the pair of gratings and the pair of transform lenses are utilized for spatially separating and recombining a multiple wavelength input signal; a mirror with a cut-out, the cut-out being of a predetermined shape and disposed in between the transform lenses and disposed within in the middle of a collimated optical path, allowing a wavelength, of the multiple wavelength input signal, to pass through, and allowing another wavelength, of the multiple wavelength input signal, to be reflected; wherein a wavelength, of the multiple wavelength input signal, which passes through the cut-out is a drop signal, and a wavelength, of the multiple wavelength input signal, which is reflected by the mirror is an express signal; and a two-axis mirror at an input side of the tunable filter, the two-axis mirror used to control the bandwidth and the wavelength of a drop signal by adjusting the angle and position of the multiple wavelength input signal relative to a first grating of the pair of gratings.