Wavelength dependent optical attenuator and variable...

Optical: systems and elements – Polarization without modulation – Depolarization

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C359S506000, C359S490020, C359S256000

Reexamination Certificate

active

07154668

ABSTRACT:
The attenuation profile of an optical system, which defines the power variation as a function of wavelength is adjusted to alter the slope of its contour. The device is useful in a wavelength division modulation system to flatten the profile of an amplifier or the like that has a non uniform power variation with wavelength. The invention adjusts the slope by first providing an input light signal that has a known polarization state, e.g., processing the input into a known phase and amplitude relation between orthogonal components, such as plane polarized at a given alignment. The signal is then passed through a series of waveplates. The waveplates have different phase retardation and orientation resulting in wavelength dependent polarization change. According to an inventive aspect, by tuning the phase retardation of multiple tunable waveplates the desired wavelength dependent polarization changes over a useful wavelength range can be produced. At the downstream end of the signal path, a polarization discriminating element such as a polarizer or beam splitter, passes or blocks light energy as a function of polarization, thus converting the variation of polarization state into a variation of amplitude.

REFERENCES:
patent: 4575849 (1986-03-01), Chun
patent: 5414541 (1995-05-01), Patel et al.
patent: 5694233 (1997-12-01), Wu et al.
patent: 5946116 (1999-08-01), Wu et al.
patent: 5978116 (1999-11-01), Wu et al.
patent: 5978125 (1999-11-01), Yao
patent: 6163393 (2000-12-01), Wu et al.
patent: 6212313 (2001-04-01), Li
patent: 6215923 (2001-04-01), Li
patent: 6219176 (2001-04-01), Terahara
patent: 6243200 (2001-06-01), Zhou et al.
patent: 6333816 (2001-12-01), Chen et al.
patent: 6816261 (2004-11-01), Patel et al.
S.E. Harris, et al., “Optical Network Synthesis Using Birefringent Crystals. I. Synthesis of Lossless Networks of Equal-Length Crystals”, Journal of the Optical Society of America, vol. 54, No. 10, pp. 1267-1279, Oct. 1964.
E.O. Ammann, et al., “Optical Network Synthesis using Birefringent Crystals. II. Synthesis of Networks Containing One Crystal, Optical Compensator, and Polarizer per Stage,” Journal of the Optical Society of America, vol. 55, No. 7, pp. 835-841, Jul. 1965.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Wavelength dependent optical attenuator and variable... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Wavelength dependent optical attenuator and variable..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Wavelength dependent optical attenuator and variable... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3720415

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.