Pixellated WDM optical components

• US 6,263,123 B1
• Filed: 03/12/1999
• Issued: 07/17/2001
• Est. Priority Date: 03/12/1999
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Bishop, David J., Giles, Clinton R.
• Primary Examiner(s): Sanghavi, Hemang
• Assistant Examiner(s): PAK, SUNG H
• Application Number:
  US09/267,848
• Time in Patent Office: 858 Days
• Field of Search: 385/15, 385/18, 385/19, 385/24, 385/37, 359/124, 359/127
• US Class Current: 385/15
• CPC Class Codes: G02B 6/12009 comprising arrayed waveguide grating [AWG] devices, i.e. with a phased array of waveguides
• CPC Class Codes: G02B 6/266 the optical element being an attenuator
• CPC Class Codes: G02B 6/2931 Diffractive element operating in reflection
• CPC Class Codes: G02B 6/29313 characterised by means for controlling the position or direction of light incident to or leaving the diffractive element, e.g. for varying the wavelength response switching G02B6/35
• CPC Class Codes: G02B 6/2938 for multiplexing or demultiplexing, i.e. combining or separating wavelengths, e.g. 1xN, NxM
• CPC Class Codes: G02B 6/3512 the optical element being reflective, e.g. mirror
• CPC Class Codes: G02B 6/356 in an optical cross-connect device, e.g. routing and switching aspects of interconnecting different paths propagating different wavelengths to (re)configure the various input and output links switching polarized beams G02B6/3594; power equalizers G02B6/356 and G02B6/3594; path selecting means H04Q11/0001
• CPC Class Codes: G02B 6/3586 Control or adjustment details, e.g. calibrating testing optical equipment G01M11/00

Abstract

A micromirror array is used to form optical apparatus useful in WDM optical networks. In one embodiment, the micromirror array is used to insert a desired attenuation in individual channels for purposes such as equalization. In another embodiment, the micromirror array is used to form an optical monitor useful as an optical spectrum analyzer.

Claims

1. Apparatus for inserting a controlled amount of attenuation in the power level of individual channels of a wavelength-division-multiplexed optical signal comprising:

a panel comprising a plurality of micromirrors that can be selectively tilted either to or not to reflect the incident light in a direction for recombination into the output beam, the plurality of micromirror being arranged in a two-dimensional array essentially a plurality of rows and a plurality of columns with at least one column exclusively for each channel of the signal and each column including a plurality of micromirrors, corresponding in numbers to the output levels to be provided;

means positioned to intercept an input wavelength-division-multiplexed input beam for separating the beam into individual channel beams, for directing the separate beams for incidence on separate columns of the micromirrors of the panel, and for recombining into the output beam the separate beams reflected in the desired direction; and

means for controlling the number of micromirrors in each column tilted away from the direction for recombination into the output beam to control the attenuation inserted.

2. The apparatus of claim 1 in which each micromirror can either reflect incident light in the desired direction for recombination or scatter it.

3. The apparatus of claim 1 in which the means to intercept the input wavelength-division-multiplexed beam is a diffraction grating.

4. The apparatus of claim 1 in which the means to intercept the input wavelength-division-multiplexed beam is an arrayed-waveguide-grating router.

5. The apparatus of claim 1 in which the means to intercept the input wavelength-division-multiplexed beam is a prism.

6. The apparatus of claim 1 in which each column includes at least hundreds of micromirrors and each channel beam is made incident simultaneously on a plurality of micromirrors of a column.

7. The apparatus of claim 6 in which the means positioned to intercept the input wavelength-division-multiplexed signal spreads each channel beam a uniform amount in the direction of the columns.

8. The apparatus of claim 1 in which each channel beam is incident on a separate group of a plurality of columns of micromirrors.

9. The apparatus of claim 7 in which each separate group includes at least a hundred micromirrors and each beam is incident on a separate group of channels.