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.

An optical proximity sensor includes a first vertical cavity surface-emitting laser configured for self-mixing interferometry to determine distance to and/or velocity of an object. The optical proximity sensor also includes a second vertical cavity surface-emitting laser configured for self-mixing interferometry to determine whether any variation in a fixed distance has occurred. The optical proximity sensor leverages output from the second vertical cavity surface-emitting laser to calibrate output from the second vertical cavity surface-emitting laser to eliminate and/or mitigate environmental effects, such as temperature changes.

In at least one embodiment, the environment sensor for sensing at least one environment parameter includes a semiconductor layer sequence, a sheath, the index of refraction of which changes as a function of the environment parameter, and a first electrical contact and a second electrical contact for supplying current to the semiconductor layer sequence. The semiconductor layer sequence has the shape of a generalized cylinder having a main axis. In directions perpendicular to the main axis, the semiconductor layer sequence is at least partly covered by the sheath. The semiconductor layer sequence has an index of refraction which is greater than the index of refraction of the sheath. The semiconductor layer sequence is designed to form laser modes within the environment sensor. Furthermore, the environment sensor is designed such that, in its normal operation, a change in the index of refraction of the sheath causes a change in the electrical resistance of the semiconductor layer sequence as a result of a change in radiation losses within the semiconductor layer sequence.

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 module includes a first laser source configured to emit first modulated light, the first modulated light being modulated laser light. The laser sensor module further includes circuitry configured to drive the first laser source with a first modulated driving current to cause the first laser source to emit the modulated laser light, a detector configured to detect the modulated laser light, which induces a photocurrent with variations resulting from modulation of the modulated laser light, and a second laser source configured to emit second modulated light. The circuitry is further configured to drive the second laser source with a second modulated driving current to cause the second laser source to emit the second modulated light. The detector is configured to detect the second modulated light. The circuitry is configured to adapt the amplitude of the second modulated driving current to induce a contribution to the photocurrent.

An optoelectronic device includes a semiconductor substrate and an optically-active structure, including epitaxial layers defining a lower distributed Bragg-reflector (DBR) stack, a quantum well structure with P- and N-doped layers disposed respectively on opposing sides of the quantum well structure, and an upper DBR stack. Electrodes are coupled to apply a bias voltage between the P- and N-doped layers. Control circuitry, disposed on the substrate, is configured to apply a forward bias voltage between the electrodes so as to cause the optically-active structure to emit an optical pulse through the upper DBR stack, and then to reverse the bias voltage between the electrodes so as to cause the optically-active structure to output an electrical pulse to the control circuitry in response to incidence of one or more of the photons, due to reflection of the optical pulse, on the quantum well structure through the upper DBR stack.

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.

In one embodiment a temperature sensor has a first sensing unit operable to provide a first pseudo-differential unipolar analog signal representing a first temperature value of a power unit, an interface circuit operable to provide a second pseudo-differential unipolar analog signal representing a second temperature value of a powered unit, a multiplexer circuit which is operable to provide a pseudo-differential unipolar multiplexed analog signal comprising the first analog signal or the second analog signal, and a first analog-to-digital converter, ADC, component operable to provide a first digital signal from the multiplexed analog signal, the first digital signal comprising a digital representation of the first analog signal or the second analog signal. Therein, the operation of the first ADC component is synchronized with a control signal designed for activating the power unit.

A laser sensor module includes a first laser source configured to emit first modulated light, the first modulated light being modulated laser light. The laser sensor module further includes circuitry configured to drive the first laser source with a first modulated driving current to cause the first laser source to emit the modulated laser light, a detector configured to detect the modulated laser light, which induces a photocurrent with variations resulting from modulation of the modulated laser light, and a second laser source configured to emit second modulated light. The circuitry is further configured to drive the second laser source with a second modulated driving current to cause the second laser source to emit the second modulated light. The detector is configured to detect the second modulated light. The circuitry is configured to adapt the amplitude of the second modulated driving current to induce a contribution to the photocurrent.

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.