Abstract: An optical signal to be detected enters single photon avalanche diode cells (SPAD) in a SPAD array and triggers photo event currents. Optical waveguides in the sensor carry an internal optical signal and a 1xN splitter divides the optical power into waveguide branches 206, 206?, . . . 206N-1. At the coupling structure, comprising 207, 207?, . . . 207N-1 positive-intrinsic-negative diode photodetector/waveguide structures, photo event currents from SPAD cells are converted to a change in the internal optical signal, by modifying internal optical signals 208, 208?, . . . 208N-1. A waveguide combiner further integrates the modified internal optical signals resulting from the photo event currents from all the cells in the sub-array. After all waveguide branches' signals are combined, a photodetector detects the internal optical signal and outputs an electrical signal.

Abstract: An optical beam scanning semiconductor device includes 1×N electrically controlled, integrated optical switch matrix and specifically designed integrated optical grating output couplers at each of N output waveguides of 1×N switch. By selecting one of the N outputs of the 1×N switch as the output of the input optical signal, an optical output beam scans in free space. Variation in the grating output coupler design enables a smart scanning device with multiple controllable beam characteristics.

Abstract: A large single-photon avalanche diode (SPAD) array is integrated with optical waveguide (WG) based devices. SPAD is a very sensitive optical detector fabricated on a semiconductor chip and WG structures are also built into the same chip. WG structures are configured to accumulate SPAD detection current. Together, they form an ultra-sensitive optical detector with high-speed response and a large aperture.

Abstract: An optical routing system for free space optical communication is disclosed. The system has a transmitter and a receiver that use free space optical communication, and includes an optical path based on waveguide where an optical signal is routed from the proximity of the transmitter to the proximity of the destination. This system has advantages in terms of mitigating line-of-sight issues, as well as potentially reducing the overall coupling loss that would be otherwise incurred due to beam divergence of free space propagation for long distance.

Abstract: An optical routing system for free space optical communication is disclosed. The system has a transmitter and a receiver that use free space optical communication, and includes an optical path based on waveguide where an optical signal is routed from the proximity of the transmitter to the proximity of the destination. This system has advantages in terms of mitigating line-of-sight issues, as well as potentially reducing the overall coupling loss that would be otherwise incurred due to beam divergence of free space propagation for long distance.

Abstract: A system and method wherein electromagnetic radiation is used for free-space communication and wireless power transfer. The electromagnetic radiation used is preferably optical radiation. The optical free-space communication and wireless power transfer system includes an optical receiver device comprising an optical filter, a photodetector, and a photovoltaic cell, wherein a band of the incoming optical radiation is extracted by the optical filter and directed to the photodetector for communication data signal detection. The remaining optical radiation is converted by the photovoltaic cell into electrical power so that the harvested energy can be stored, used as the power source of the photodetector, or used as the power source of external devices.

Abstract: Small form-factor, sensitive and efficient waveguide devices capable of nondispersive infrared gas or liquid sensing and photocatalysis are designed based on photonic integrated circuits. The devices comprise three-dimensional optical waveguiding structures and preferably integrated light sources and photodetectors. Since the length of the waveguide scales with the number of waveguiding layers, a plurality of layers is used to design high-sensitivity sensors and high-efficiency photocatalysis devices. In one embodiment, titanium dioxide absorbs ultraviolet light to generate an electron-hole pair which, in the presence of water and oxygen, generates radicals that react with and mineralize undesirable organic compounds, such as the lipid membranes that envelope and protect viruses such as Coronavirus Disease 2019 (COVID-19), allowing to pry apart the membranes and destroy the cells.

Abstract: An apparatus has an input waveguide to receive light. An optical power splitter is connected to the input waveguide to form split signals. An array of waveguides receives the split signals. A phase tuning region includes electrodes within a cladding structure surrounding cores of the array of waveguides. The phase tuning region produces an electro-optic effect under the control of a phase tuning control circuit applying an electric field to the electrodes to render phase difference split signals within the array of waveguides. Output array waveguides emit the phase difference split signals as steered beams based on relative phase differences among the phase difference split signals.

Abstract: An optical switch system for dropping a ROADM node is presented. The switch system includes an N×M structure having two layers. A first layer includes optical splitters, each splitter receiving a multiplexed input signal and outputting a first multiplexed output signal. A second layer includes switches receiving the first multiplexed output signals from the optical splitters and generating a second multiplexed output signal. The second multiplexed output signal is typically one of the first multiplexed output signals. An optional third layer, which includes optical filters, receives the second multiplexed output signal from the switches and produces a non-multiplexed, single-wavelength output signal.

Abstract: An optical switch system for dropping a ROADM node is presented. The switch system includes an N×M structure having two layers. A first layer includes optical splitters, each splitter receiving a multiplexed input signal and outputting a first multiplexed output signal. A second layer includes switches receiving the first multiplexed output signals from the optical splitters and generating a second multiplexed output signal. The second multiplexed output signal is typically one of the first multiplexed output signals. An optional third layer, which includes optical filters, receives the second multiplexed output signal from the switches and produces a non-multiplexed, single-wavelength output signal.

Abstract: The present invention is directed to Y-branch digital optical switching and optical attenuator devices, which enhance the security of optical communications channels in the event of an electrical power loss.

Abstract: Polarization independent optical isolator/circulator devices based on Mach-Zehnder interferometers. The devices utilize either polarization splitting and nonreciprocal polarization conversion or nonreciprocal phase shift within the interferometric arm. For devices with nonreciprocal phase shift, the relative phase difference is 0° in the forward propagation direction and 180° in the backward propagation direction, or vice versa, so that light goes into a bar or cross port depending on the propagation direction. The devices have advantages over previous designs in the use of inexpensive device components, simple alignment, minimal space requirement, and negligible polarization mode dispersion or polarization dependent loss. In addition, the devices can be made in a waveguide form with minimal loss and with high fabrication ease. An additional phase compensator and/or a variable attenuator can be integrated in order to relax the fabrication tolerances.

Abstract: Polarization independent optical isolator/circulator devices based on Mach-Zehnder interferometers. The devices utilize either polarization splitting and nonreciprocal polarization conversion or nonreciprocal phase shift within the interferometric arm. For devices with nonreciprocal phase shift, the relative phase difference is 0° in the forward propagation direction and 180° in the backward propagation direction, or vice versa, so that light goes into a bar or cross port depending on the propagation direction. The devices have advantages over previous designs in the use of inexpensive device components, simple alignment, minimal space requirement, and negligible polarization mode dispersion or polarization dependent loss. In addition, the devices can be made in a waveguide form with minimal loss and with high fabrication ease. An additional phase compensator and/or a variable attenuator can be integrated in order to relax the fabrication tolerances.

Abstract: The present invention is directed to Y-branch digital optical switching and optical attenuator devices, which enhance the security of optical communications channels in the event of an electrical power loss.

Abstract: Polarization independent optical isolator/circulator devices based on Mach-Zehnder interferometers. The devices utilize either polarization splitting and nonreciprocal polarization conversion or nonreciprocal phase shift within the interferometric arm. For devices with nonreciprocal phase shift, the relative phase difference is 0° in the forward propagation direction and 180° in the backward propagation direction, or vice versa, so that light goes into a bar or cross port depending on the propagation direction. The devices have advantages over previous designs in the use of inexpensive device components, simple alignment, minimal space requirement, and negligible polarization mode dispersion or polarization dependent loss. In addition, the devices can be made in a waveguide form with minimal loss and with high fabrication ease. An additional phase compensator and/or a variable attenuator can be integrated in order to relax the fabrication tolerances.

Abstract: A device and method for optical isolation for use in optical systems is disclosed. The device provides for a waveguide optical isolator fabricated using two arms, made of optical waveguides comprising magneto-optical material, in a Mach-Zehnder interferometer configuration. The device of the present invention operates using the TM mode of a light wave and, thus, does not require phase-matching of TM and TE modes. Further, the present invention does not use polarizers to extinguish the optical feed-back.

Abstract: Polarization independent optical isolator/circulator devices based on Mach-Zehnder interferometers. The devices utilize either polarization splitting and nonreciprocal polarization conversion or nonreciprocal phase shift within the interferometric arm. For devices with nonreciprocal phase shift, the relative phase difference is 0° in the forward propagation direction and 180° in the backward propagation direction, or vice versa, so that light goes into a bar or cross port depending on the propagation direction. The devices have advantages over previous designs in the use of inexpensive device components, simple alignment, minimal space requirement, and negligible polarization mode dispersion or polarization dependent loss. In addition, the devices can be made in a waveguide form with minimal loss and with high fabrication ease. An additional phase compensator and/or a variable attenuator can be integrated in order to relax the fabrication tolerances.

Abstract: Polarization independent optical isolator/circulator devices based on Mach-Zehnder interferometers. The devices utilize either polarization splitting and nonreciprocal polarization conversion or nonreciprocal phase shift within the interferometric arm. For devices with nonreciprocal phase shift, the relative phase difference is 0° in the forward propagation direction and 180° in the backward propagation direction, or vice versa, so that light goes into a bar or cross port depending on the propagation direction. The devices have advantages over previous designs in the use of inexpensive device components, simple alignment, minimal space requirement, and negligible polarization mode dispersion or polarization dependent loss. In addition, the devices can be made in a waveguide form with minimal loss and with high fabrication ease. An additional phase compensator and/or a variable attenuator can be integrated in order to relax the fabrication tolerances.

Abstract: A device and method for optical isolation for use in optical systems is disclosed. The device provides for a waveguide optical isolator fabricated using two arms, made of optical waveguides comprising magneto-optical material, in a Mach-Zehnder interferometer configuration. The device of the present invention operates using the TM mode of a light wave and, thus, does not require phase-matching of TM and TE modes. Further, the present invention does not use polarizers to extinguish the optical feedback.

Abstract: Polarization independent optical isolator/circulator devices based on Mach-Zehnder interferometers. The devices utilize either polarization splitting and nonreciprocal polarization conversion or nonreciprocal phase shift within the interferometric arm. For devices with nonreciprocal phase shift, the relative phase difference is 0° in the forward propagation direction and 180° in the backward propagation direction, or vice versa, so that light goes into a bar or cross port depending on the propagation direction. The devices have advantages over previous designs in the use of inexpensive device components, simple alignment, minimal space requirement, and negligible polarization mode dispersion or polarization dependent loss. In addition, the devices can be made in a waveguide form with minimal loss and with high fabrication ease. An additional phase compensator and/or a variable attenuator can be integrated in order to relax the fabrication tolerances.