Claims
- 1. A bandpass filter comprising:
a) a first optical cavity for receiving an optical signal beam, the first optical cavity comprising;
i) a first thin film spacer, and ii) a first pair of dielectric reflector stacks surrounding the first thin film spacer, b) a second optical cavity having a first side disposed toward and in optical communication with the second side of said first optical cavity to provide a transmission bandwidth BW defined between the wavelengths at which the transmission decrease by 3 dB, the second optical cavity comprising;
i) a second thin film spacer, and ii) a second pair of dielectric reflector stacks surrounding the second thin film spacer, c) wherein the transmission T has a single maxima within BW with continuously decreasing transmission across the BW, such that the maximum ripple in GD over BW is less than about 1 ps. (add DC's 0.5)
- 2. A bandpass filter according to claim 1 wherein the transmission decrease over bandwidth BW has a substantially Gaussian filter shape and T is greater than about 90%.
- 3. A bandpass filter according to claim 1 wherein the transmission decrease over bandwidth BW has a substantially Bessel-Thompson filter shape and T is greater than about 90%.
- 4. A bandpass filter accordingly to claim 1 and having a single maxima in transmission over a 3 dB BW of less than 1 nm and exhibiting maximum in GD ripple of less than 1/(2×3 dB BW)
- 5. A narrow bandpass filter having a single maxima in transmission over a 3 dB BW of less than 1 nm and exhibiting a maximum ripple in GD over BW is less than about 1 ps.
- 6. A bandpass filter accordingly to claim 5 exhibiting a maximum ripple in GD over BW of less than about 0.5 ps
- 7. A bandpass filter accordingly to claim 1 wherein the physical thickness of each spacer is less than about 200 microns.
- 8. A bandpass filter accordingly to claim 1 wherein the physical thickness of at least one spacer is more than about 200 microns.
- 9. A method of combining or separating optical signal channels in a WDM communication system, the method comprising:
a) providing a plurality of optical signal propagating between one or more common waveguides, b) modulating the intensity of the optical channel signals at a bit-rate of BR, c) interposing a narrow bandpass MLIF to selectively reflect or transmit at least one of the optical channel signals, wherein the narrow passband filter has a 3 dB bandwidth BW in which 3 dB BW is no more than about 2 BR and the maximum ripple in GD across BW of less than about 1/(2 BW).
- 10. A method of combining or separating optical signal channels in a WDM communication system, the method comprising:
a) providing a plurality of optical signal propagating between one or more common waveguides, b) modulating the intensity of the optical channel signals at a bit-rate of BR, c) interposing a narrow bandpass MLEF to selectively reflect or transmit at least one of the optical channel signals, wherein the narrow passband filter has a 3 dB bandwidth BW in which BW is no more than about 2 BR and the maximum ripple in GD across BW is less than about 1/(2 BW).
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to provisional application having serial No. 60/315,344 entitled “Low Chromatic Dispersion Filter for WDM” filed on Aug. 29, 2001, which is incorporated herein by reference.
Provisional Applications (1)
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Number |
Date |
Country |
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60315344 |
Aug 2001 |
US |