A method and optical tap is provided for forming a monitor signal that is a measure of optical power in a guided mode output of an optical modulator. The method and optical tap may monitor the guided mode power without tapping the guided mode light, even when optical power of the radiation modes is non-complementary to that of the output mode. Light from the radiation modes of the optical modulator is coupled into the wall of a capillary through a front face. Separate portions of the radiation mode light are reflected into photodetectors, which form photocurrents that are incoherently added to form the monitor signal.
An optical waveguide monitor equipped with an output light monitor having a decreased restriction in the dimensions and form thereof, a high reliability and a low production cost includes an optical waveguide element (having a plurality of surface waveguide portions, a connecting portion for converging and connecting the surface waveguide portions and an output light-outputting waveguide portion connected to the connecting portion each formed on a dielectric substrate plate; an output light optical fiber connected to an output end of the output light-outputting waveguide portion, a reinforcing capillary for reinforcing a connection between the optical waveguide element and the output light optical fiber and a monitoring light receiving means, wherein the reinforcing capillary has a hole or groove for containing and supporting the output light optical fiber therein, a connecting face thereof bonded to an output end face of the substrate, and a terminal surface opposite to the connecting face, to thereby enable at least one member of the reinforcing capillary per se and a monitoring light optical fiber located within the capillary to receive the monitoring light outputted from the optical waveguide element, to transmit it therethrough and to output it to the outside of the capillary, and the monitoring light receiving means is located in a position suitable to receive the monitoring light outputted to the outside of the reinforcing capillary and has a photoelectric conversion element.
An optical waveguide monitor equipped with an output light monitor having a decreased restriction in the dimensions and form thereof, a high reliability and a low production cost includes an optical waveguide element (having a plurality of surface waveguide portions, a connecting portion for converging and connecting the surface waveguide portions and an output light-outputting waveguide portion connected to the connecting portion each formed on a dielectric substrate plate; an output light optical fiber connected to an output end of the output light-outputting waveguide portion, a reinforcing capillary for reinforcing a connection between the optical waveguide element and the output light optical fiber and a monitoring light receiving means, wherein the reinforcing capillary has a hole or groove for containing and supporting the output light optical fiber therein, a connecting face thereof bonded to an output end face of the substrate, and a terminal surface opposite to the connecting face, to thereby enable at least one member of the reinforcing capillary per se and a monitoring light optical fiber located within the capillary to receive the monitoring light outputted from the optical waveguide element, to transmit it therethrough and to output it to the outside of the capillary, and the monitoring light receiving means is located in a position suitable to receive the monitoring light outputted to the outside of the reinforcing capillary and has a photoelectric conversion element.
An optical waveguide element having a plurality of surface waveguide portions. A connecting portion for connecting the surface waveguide portions. An output light-outputting waveguide portion connected to the connecting portion each on a dielectric substrate. An output light optical fiber connected to an output end of the output light-outputting waveguide portion. A reinforcing capillary for a connection between the optical waveguide element and the output light optical fiber and a monitoring light receiver. The reinforcing capillary has a hole or groove for supporting the output light optical fiber, a connecting face bonded to an output end face of the substrate, and a terminal surface opposite to the connecting face. The light outputted from the optical waveguide element, therethrough to the outside of the capillary.
The invention relates to an optical waveguide device for monitoring a characteristics of light, e.g. a wavelength. The device incorporates a waveguide, such as an optical fiber, with an embedded tilted Bragg grating operating in a regime of wavelength detuning. The grating is designed to disperse light azimuthally in two or more different directions about the fiber axis, said directions changing with wavelength. A photodetector array is provided for detecting the azimuthal distribution of light. A processor coupled to the photodetector array determines wavelength information from the detected azimuthal distribution of the out-coupled light.
