Optical: systems and elements – Optical modulator – Light wave temporal modulation
Patent
1992-04-29
1993-05-18
Arnold, Bruce Y.
Optical: systems and elements
Optical modulator
Light wave temporal modulation
359288, 359579, 359586, 359588, G02F 107, G02F 101, G02B 2700, G02B 110
Patent
active
052125840
ABSTRACT:
A tunable etalon filter is formed by placing mirrors on either side of a spacer of a material which has a relatively large rate of change of refractive index with temperature, and coupling the filter to a thermoelectric cooler to control the temperature of the spacer and, therefore, the index of refraction of the spacer. More specifically, the spacer can be a silicon wafer, or a wafer of zinc sulfide or zinc selenide. The mirrors can be formed of quarter wavelength layer pairs of dielectric coatings of high and low refractive index material. The thermoelectric cooler, which can be coupled to a heat sink, controls the temperature of the spacer by either heating or cooling the spacer. In operation the filter is coarse tuned by adjusting its angle relative to the angle of a received optical signal. It is then fine tuned to the signal by adjusting the temperature of the spacer. The advantages of this filter are: large tunability by angle tuning; fine tuning by temperature; large free-spectral-range; narrow passband; low insertion loss; and high reliability.
REFERENCES:
patent: 4782492 (1988-11-01), McMahon et al.
"Electrically Tunable Optical Filter for Infrared Wavelength Using Liquid Crystals in a Fabry-Perot Etalon" J. S. Patel, et al., Appl. Phys Lett 57 (17) 22 Oct. 1990, pp. 1718-1720.
"Angle-Tuned Etalon Filters for Optical Channel Selection in High Density Wavelength Division Multiplexed Systems" A. Frenkel and C. Lin, J. Lightwave Tech., vol. 7, No. 4 Apr. 1989 pp. 615-624.
Arnold Bruce Y.
AT&T Bell Laboratories
Lester Evelyn A.
Weiss E.
LandOfFree
Tunable etalon filter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Tunable etalon filter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tunable etalon filter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-807929