Abstract: A polarization splitting grating coupler (PSGC) connects an optical signal from an optical element, such as a fiber, to an optoelectronic integrated circuit. The PSGC separates a received optical signal into two orthogonal polarizations and directs the two polarizations to separate waveguides on an integrated circuit. Each of the two separated polarizations can then be processed, as needed for a particular application, by the integrated circuit. A PSGC can also operate in the reverse direction, and couple two optical signals from an integrated circuit to two respective orthogonal polarizations of one optical output signal sent off chip to an optical fiber.

Abstract: Various configurations of elongate scattering elements in an optical waveguide grating coupler for coupling light between a planar waveguide and an optical element such as an optical fiber, where the light may have a Gaussian intensity distribution. The elongate scattering elements are preferably curved, and in some embodiments, the scattering elements have elliptically curved shape. One or more of the elongate scattering elements may be segmented into various geometrical shapes, such as rectangular, square, circular and elliptical. The elongate scattering elements have at least one characteristic selected from the group consisting of grating width, height, spacing, depth and index of refraction forming the elongate scattering elements, where the magnitude of the at least one characteristic varies irregularly with position along the guiding portion of the optical waveguide grating coupler.

Abstract: An optical waveguide grating coupler for coupling light between a planar waveguide and an optical element such as an optical fiber. The optical waveguide grating coupler includes a grating comprising a plurality of elongate scattering elements. The optical waveguide grating coupler is preferably flared, and in various embodiments has hyperbolically shaped sidewalls. The elongate scattering elements are preferably curved, and in some embodiments, the scattering elements have elliptically curved shapes. Preferably, the elongated scattering elements have grating widths selected to accommodate the desired optical intensity distribution.

Abstract: An optical wavelength grating coupler incorporating one or more distributed Bragg reflectors (DBR) or other reflective elements to enhance the coupling efficiency thereof. The grating coupler has a grating comprising a plurality of scattering elements adapted to scatter light along a portion of an optical path, and the one or more DBRs are positioned with respect to the grating such that light passing through the grating towards the substrate of the grating coupler is reflected back by DBRs toward the grating. The DBR comprises a multilayer stack of various materials and may be formed on the substrate of the grating coupler. The grating coupler may include a gas-filled cavity, where the cavity is formed by a conventional etching process and is used to reflect light toward the grating. The grating coupler may also incorporate an anti-reflection coating to reduce reflective loss on the surface of the grating.

Abstract: This application describes, among others, wafer designs, testing systems and techniques for wafer-level optical testing by coupling probe light from top of the wafer.

Abstract: A fiber to chip coupling connecting an optical fiber to an integrated circuit. A section of fiber is laid on top of the surface of the chip, where the end of the fiber has been cut at an angle to form an angled tip. The angled tip has a flat surface which reflects light down to a waveguide grating coupler disposed on the integrated circuit. Light is reflected off the reflective surface of the angled tip by total internal reflection. The waveguide grating coupler is designed to accept the slightly diverging light beam from the reflective surface of the angled tip of the fiber. Light can also propagate through the fiber to chip coupler in the opposite direction, up from the substrate through the waveguide grating and into an optical fiber after bouncing off the reflective surface of the angled tip.

Abstract: Electronically controllable arrayed waveguide gratings (AWGs) with integrated phase error compensation for each individual arm of the array of waveguides. These AWGs and associated methods for static and dynamic phase compensation enable the fabrication of tunable AWGs which can track one or more drifting channels of an AWG.

Abstract: A polarization splitting grating coupler (PSGC) connects an optical signal from an optical element, such as a fiber, to an optoelectronic integrated circuit. The PSGC separates a received optical signal into two orthogonal polarizations and directs the two polarizations to separate waveguides on an integrated circuit. Each of the two separated polarizations can then be processed, as needed for a particular application, by the integrated circuit. A PSGC can also operate in the reverse direction, and couple two optical signals from an integrated circuit to two respective orthogonal polarizations of one optical output signal sent off chip to an optical fiber.

Abstract: A multi-wavelength light source with a gain medium and an optical equalizer. The gain medium emits light of a plurality of wavelengths in response to pumping. The gain medium is disposed in an optical cavity that repetitively passes light through the gain medium. The optical cavity supports a plurality of different optical modes having wavelengths coinciding with the plurality of wavelengths emitted by the gain medium. The optical equalizer is also in the optical cavity. The optical equalizer adjusts the optical power of at least one of the different optical modes so as to provide more even optical power distribution among the optical modes propagating through the optical cavity.

Abstract: A polarization splitting grating coupler (PSGC) connects an optical signal from an optical element, such as a fiber, to an optoelectronic integrated circuit. The PSGC separates a received optical signal into two orthogonal polarizations and directs the two polarizations to separate waveguides on an integrated circuit. Each of the two separated polarizations can then be processed, as needed for a particular application, by the integrated circuit. A PSGC can also operate in the reverse direction, and couple two optical signals from an integrated circuit to two respective orthogonal polarizations of one optical output signal sent off chip to an optical fiber.

Abstract: An optical waveguide grating coupler for coupling light between a planar waveguide and an optical element such as an optical fiber. The optical waveguide grating coupler includes a grating comprising a plurality of elongate scattering elements. The optical waveguide grating coupler is preferably flared, and in various embodiments has hyperbolically shaped sidewalls. The elongate scattering elements are preferably curved, and in some embodiments, the scattering elements have elliptically curved shapes. Preferably, the elongated scattering elements have grating widths selected to accommodate the desired optical intensity distribution.

Abstract: An optical wavelength grating coupler incorporating one or more distributed Bragg reflectors (DBR) or other reflective elements to enhance the coupling efficiency thereof. The grating coupler has a grating comprising a plurality of scattering elements adapted to scatter light along a portion of an optical path, and the one or more DBRs are positioned with respect to the grating such that light passing through the grating towards the substrate of the grating coupler is reflected back by DBRs toward the grating. The DBR comprises a multilayer stack of various materials and may be formed on the substrate of the grating coupler. The grating coupler may include a gas-filled cavity, where the cavity is formed by a conventional etching process and is used to reflect light toward the grating. The grating coupler may also incorporate an anti-reflection coating to reduce reflective loss on the surface of the grating.