Methods and apparatus for a controlling a stimulus source to direct photons to a pixel in a pixel array contained in a detector system, analyzing a response of the pixel in the pixel array; and generating an alert based on the response of the pixel in the pixel array. Example stimulus sources include a conductive trace, a PN junction, and a current source.

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

A laser sensor includes a laser source configured to emit a laser beam, and optics configured to project the laser beam as a one- or two-dimensional patterned laser beam onto an object to be examined, such that a distance of the patterned laser beam from the laser source varies along the patterned laser beam projected on the object. The laser sensor further includes a detector configured to determine a self-mixing interference signal generated by laser light of the patterned laser beam reflected from the object back into the laser source, and circuitry configured to analyze a spectrum of the self-mixing interference signal and extract from the spectrum of the self-mixing interference signal multiple frequencies that are indicative of at least one of the following: multiple distances along the patterned laser beam from the laser source, or multiple velocities along the patterned laser beam with respect to the laser source.

In at least one embodiment, the optoelectronic semiconductor device comprises a carrier, a first semiconductor laser configured to emit a first laser radiation and applied on the carrier, and a multi-mode waveguide configured to guide the first laser radiation and also applied on the carrier, wherein the multi-mode waveguide comprises at least one furcation and a plurality of branches connected by the at least one furcation.

Self-mixing interferometry (SMI) sensors may include vertical cavity surface emitting lasers (VCSEL), photodetectors, and microelectromechanical systems (MEMS). The VCSEL, photodetectors, and MEMS may be vertically stacked. The MEMS may be moveable with respect to a VCSEL and may change a cavity length associated with the VCSEL. By changing the cavity length associated with the VCSEL, certain properties of emitted light may be changed, such as a wavelength value of the emitted light.

An optoelectronic device includes a base chip, including a silicon die having a photodiode disposed at its front surface and a first anode contact and a first cathode contact disposed on the front surface. A laser diode driver circuit on the silicon die supplies an electrical drive signal between the first anode contact and the first cathode contact. An emitter chip includes a III-V semiconductor die, which is mounted with its front side facing toward the front surface of the silicon die. A second anode contact and a second cathode contact are disposed on the front side of the III-V semiconductor die in electrical communication with the first anode contact and the first cathode contact. A VCSEL is disposed on the front side of the III-V semiconductor die in coaxial alignment with the photodiode and receives the drive signal from the second anode contact and the second cathode contact.

Disclosed herein are electronic devices having touch input surfaces. A user's touch input or press on the touch input surface is detected using a set of lasers, such as vertical-cavity surface-emitting lasers (VCSELs) that emit beams of light toward the touch input surface. The user's touch causes changes in the self-mixing interference within the VCSEL of the emitted light with reflected light, such as from the touch input surface. Deflection and movement (e.g., drag motion) of the user's touch is determined from detected changes in the VCSELs' operation due to the self-mixing interference.

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.