Abstract: Disclosed herein are apparatus and methods for acoustic imaging. The disclosed embodiments include an optical sensor. The optical sensor may include an acoustic stack. The acoustic stack may include a backing layer that supports an optical layer. The optical layer may include an optical waveguide and a tuning device configured to tune an optical propagation property of the optical waveguide. The optical waveguide may include a core region and one or more cladding regions. The one or more cladding regions may have optical refractive index less than that of the core region.

Abstract: An apparatus for imaging a target and a process of making the apparatus are provided. The apparatus includes a housing and a distal portion. The distal portion includes an acoustic subarray on a first substrate configured to transmit acoustic signals toward the target. The distal portion includes an optical subarray on a second substrate, configured to detect acoustic signals from the target. The distal portion includes an input/output (I/O) region including one or more optical I/O channels. The one or more optical I/O channels is configured to bend optical signals between the optical subarray and the one or more optical I/O channels.

Abstract: The optical sensor circuit is an optical circuit for routing input optical signals through an array of optical sensors. The optical sensor circuit includes an optical input port for receiving a plurality of input optical signals within a single input channel, where each of the input optical signals has a unique wavelength associated therewith. A wavelength-division demultiplexer is coupled to the optical input port to demultiplex the plurality of input optical signals, and a plurality of optical sensors are coupled to the wavelength-division demultiplexer for respectively receiving the plurality of input optical signals and outputting a corresponding plurality of output optical signals. A wavelength-division multiplexer is coupled to the plurality of optical sensors to multiplex the plurality of output optical signals into a single output channel, and an optical output port is coupled to the wavelength-division multiplexer for outputting the plurality of output optical signals in the single output channel.

Abstract: A photonic aerosol particle sensor includes a microfluidic sensor chamber in which is disposed a plurality of photonic waveguide resonators each having a photonic waveguide on an underlying substrate, along a separate waveguide resonator path with a lateral width different than that of other photonic waveguide resonators. All waveguides in the plurality have a common vertical thickness of a common waveguide material having a refractive index that is larger than that of the underlying substrate material. An optical input connection couples light into the waveguide resonators. An aerosol particle input fluidically connected to the microfluidic chamber fluidically conveys aerosol particles to the chamber, and an aerosol particle output fluidically connected to the microfluidic chamber fluidically conveys aerosol particles out of the chamber.

Abstract: A photonic aerosol particle sensor includes a microfluidic sensor chamber in which is disposed a plurality of photonic waveguide resonators each having a photonic waveguide on an underlying substrate, along a separate waveguide resonator path with a lateral width different than that of other photonic waveguide resonators. All waveguides in the plurality have a common vertical thickness of a common waveguide material having a refractive index that is larger than that of the underlying substrate material. An optical input connection couples light into the waveguide resonators. An aerosol particle input fluidically connected to the microfluidic chamber fluidically conveys aerosol particles to the chamber, and an aerosol particle output fluidically connected to the microfluidic chamber fluidically conveys aerosol particles out of the chamber.

Abstract: A photonic aerosol particle sensor includes a plurality of photonic waveguide resonators each having a photonic waveguide disposed along a separate waveguide resonator path and each photonic waveguide having a lateral waveguide width different than the waveguide width of other photonic waveguide resonators in the plurality. All waveguides in the plurality of photonic waveguide resonators have a common vertical thickness and are formed of a common photonic waveguide material. An optical input connection couples light into the waveguide resonators. A particle input conveys aerosol particles toward the waveguide resonators and an aerosol particle output conveys aerosol particles away from the waveguide resonators. At least one optical output connection is optically connected to accept light out of the plurality of photonic waveguide resonators to provide a signal indicative of at least one characteristic of the aerosol particles to be analyzed.

Abstract: An integrated optical modulator array useful for modulating light at different wavelengths in the same optical band includes multiple GeSi waveguides on a substrate. Each GeSi waveguide has a different width and is coupled to electrodes to form an electro-absorption modulator. A stressor material, such as SiN, disposed between the GeSi waveguides in the optical modulators applies a strain to the GeSi waveguides. Because each GeSi waveguide has a different width, it experiences a different strain. This difference can be a difference in magnitude, type (homogeneous v. inhomogeneous, compressive v. tensile), or both. The different strains shift the bandgaps of the Ge in the GeSi waveguides by different amounts, shifting the optical absorption edges for the GeSi waveguides by different amounts. Put differently, the stressor layer strains each GeSi modulator differently, causing each GeSi modulator to operate at a different wavelength.

Abstract: An integrated optical modulator array useful for modulating light at different wavelengths in the same optical band includes multiple GeSi waveguides on a substrate. Each GeSi waveguide has a different width and is coupled to electrodes to form an electro-absorption modulator. A stressor material, such as SiN, disposed between the GeSi waveguides in the optical modulators applies a strain to the GeSi waveguides. Because each GeSi waveguide has a different width, it experiences a different strain. This difference can be a difference in magnitude, type (homogeneous v. inhomogeneous, compressive v. tensile), or both. The different strains shift the bandgaps of the Ge in the GeSi waveguides by different amounts, shifting the optical absorption edges for the GeSi waveguides by different amounts. Put differently, the stressor layer strains each GeSi modulator differently, causing each GeSi modulator to operate at a different wavelength.

Abstract: A photonic aerosol particle sensor includes a plurality of photonic waveguide resonators each having a photonic waveguide disposed along a separate waveguide resonator path and each photonic waveguide having a lateral waveguide width different than the waveguide width of other photonic waveguide resonators in the plurality. All waveguides in the plurality of photonic waveguide resonators have a common vertical thickness and are formed of a common photonic waveguide material. An optical input connection couples light into the waveguide resonators. A particle input conveys aerosol particles toward the waveguide resonators and an aerosol particle output conveys aerosol particles away from the waveguide resonators. At least one optical output connection is optically connected to accept light out of the plurality of photonic waveguide resonators to provide a signal indicative of at least one characteristic of the aerosol particles to be analyzed.