Optical add/drop multiplexer
AssigneeIndustrial Technology Research Institute
InventorsShih-Chiang Lin, Wei-Jen Chou, Hsin-Chien Chiang, Jiun-Shyong Wu
Life of this patent
Estimating the term…
Abstract
An optical add/drop multiplexer capable of extracting signals from within a specified waveband in a group of signals containing various wavelengths, and then adding back a new set of signals also within the specified waveband. The multiplexer includes an optical filter plate, a plane reflector and three graded-index lenses. Using a single optical filtering plate and a plane reflector to carry out multiple reflections, intra-band isolation of light signals is improved and cost of production is reduced.
Claims8
An optical add/drop multiplexer, comprising:
- a first lens for receiving and emitting a group of light signals, wherein the light signals includes a spectrum of wavelengths;
- an optical filtering device that includes an optical filter plate and a reflector, wherein the optical filter plate receives the group of incoming light signals and permits the transmission of signals within a specified waveband through the filter plate so that signals outside the specified waveband and a remaining signals within a specified waveband are reflected back and forth between the filter plate and the reflector several times, and the signals from the last reflection from the filter plate emerge as a group of output signals that contain the low-level signals within the specified waveband;
- a second lens for receiving signals from the specified waveband after passing through the optical filter plate to become dropout signals for readout, wherein the second lens is also capable of receiving add-in signals within the specified waveband and delivering the add-in signals to the optical filtering device where the add-in signals are permitted to penetrate;
- and
- a third lens for integrating the output signals with the low-level signals in the specified waveband and the add-in signals and then transmitting the signals thus integrates as a group of output signals.
An optical add/drop multiplexer implemented on a piece of glass, comprising a glass substrate, wherein:
- the first surface includes an anti-reflection coating, a reflection coating, and an output coating, and the second surface includes an optical filtering layer;
- the anti-reflection coating receives a group of light signals that contains signals of various wavelengths and re-transmits them into the substrate;
- the optical filtering layer receives the group of signals coming from the anti-reflection coating and permits only signals within a specified waveband to pass through and become read-out signals;
- other signals outside the specified waveband are reflected back and forth between the optical filtering layer and the reflection coating several times inside the glass medium, and the signals from the last reflection from the filtering layer emerge from the output coating as a group of output signals with the low-level signals within the specified waveband;
- the optical filtering layer is further capable of receiving add-in signals within the specified waveband;
- and the output coating integrates the signals after several internal reflections and the add-in signals, and then transmits the integrated signals as a group of output signals.
Dependencies are inferred from the claim text.