Optical device with non-equally spaced output ports
View Patent ↗The invention relates to multiport routing devices for routing optical signals which also provide beam attenuation by imparting a controllable offset between an optical beam and a selected optical port. A multiport optical routing device of the present invention has a plurality of non-equally spaced optical ports disposed in a row to enable beam offset for attenuation without substantially increasing optical crosstalk between adjacent ports in a compact port arrangement.
1. A multiport optical routing device for routing and modifying an optical signal, comprising:
an input optical port for receiving the optical signal;
a plurality of output optical ports disposed in a row comprising first, second and third consecutive output optical ports; and,
a beam director optically coupled to the input optical port for receiving at least a portion of the optical signal therefrom and for directing said at least a portion of the optical signal as a light beam at an angle controlled by the beam director for coupling into one of the output optical ports;
wherein the first, second and third consecutive output optical ports are non-uniformly spaced with a first distance d 1 between the first and second output optical ports that differs from a second distance d 2 between the second and third output optical ports by at least 10%.
2. The device of claim 1 , wherein each three consecutive output optical ports from the plurality of output optical ports are non-equally spaced with inter-port distances between adjacent output optical ports differing by at least 10%.
3. The device of claim 1 , wherein each of the output optical ports having two adjacent output optical ports at opposite sides thereof is at least 10% further away from one of the adjacent output optical ports than from the other of the two adjacent output optical ports.
4. The device of claim 2 , wherein a ratio of the second distance d 2 to the first distance d 1 is between 1.2 and 1.6 inclusive.
5. The device of claim 2 , wherein the first distance d 1 is between 100 μm and 150 μm, and d 2 is between 150 and 300 μm.
6. The device of claim 2 , wherein the first distances d 1 is between 200 and 300 μm, and d 2 is between 300 and 600 μm.
7. The device of claim 1 , further comprising a switching lens having a first optical axis for converting an angular displacement of the light beam arriving from the beam director into a lateral displacement corresponding to a position of a selected one of the plurality of output optical ports.
8. The device of claim 7 , wherein the beam director is operable to control the angle of the light beam so as to direct the light beam along an optical path towards the second output optical port for coupling thereinto, and is further operable to change the angle so as to at least partially shift the light beam away from an alignment with the second output optical port towards one of the first and third output optical ports that is distanced farther away from the second output optical port so as to provide a controllable optical loss for light coupled into the second output optical port without causing light of the light beam to leak into adjacent optical ports.
9. The device of claim 8 , further comprising a wavelength dispersing element defining a dispersion plane for dispersing the optical signal received from the input optical port into a plurality of light beams having different central wavelengths, wherein the optical beam director comprises an actuation array for selectively deflecting one or more of the light beams along optical paths in a switching plane at one or more angles controlled by the beam director for coupling into selected output optical ports with controllable beam offsets.
10. The device of claim 9 , wherein the wavelength dispersing element comprises one of a dispersion grating, a prism, and an array waveguide grating (AWG).
11. The device of claim 9 , wherein the actuation array comprises a micro-electromechanical systems (MEMS) device.
12. The device of claim 9 , wherein the actuation array comprises a liquid crystal phase array.
13. The device of claim 7 , further including a fiber array comprising a plurality of fibers coupled to the input port and the plurality of output ports for transmitting and receiving optical signals, respectively.
14. The device of claim 1 , wherein the plurality of output optical ports forms one row of a two-dimensional array of optical ports, wherein each row thereof comprises at least three consecutive output optical ports that are non-equally spaced so that consecutive distances between adjacent output optical ports in a row vary by at least 10% along the row.