An optoelectronic module includes a light guide arranged to receive light, such as ambient light or light reflected by an object. The light guide has a diffractive grating that includes multiple sections, each of which is tuned to a respective wavelength or narrow band of wavelengths. The module further includes multiple photosensitive elements, each of which is arranged to receive light diffracted by a respective one of the sections of the diffractive grating. The module can be integrated, for example, as part of a spectrometer or other apparatus for optically determining characteristics of an object.

A measurement system is provided with an array of laser diodes with one or more Bragg reflectors. At least a portion of the light generated by the array is configured to penetrate tissue comprising skin. A detection system configured to: measure a phase shift, and a time-of-flight, of at least a portion of the light from the array of laser diodes reflected from the tissue relative to the portion of the light generated by the array; generate one or more images of the tissue; detect oxy- or deoxy-hemoglobin in the tissue; non-invasively measure blood in blood vessels within or below a dermis layer within the skin; measure one or more physiological parameters based at least in part on the non-invasively measured blood; and measure a variation in the blood or physiological parameter over a period of time.

Disclosed is an optical sensor, including an external cavity laser configured to output sensing light and reference light; and a photodetector configured to detect a beating signal by an interference of the sensing light and the reference light output from the external cavity laser, in which the external cavity laser includes a reflecting filter including a sensing grating, to which a sensing object is attachable, and a reference grating, which is disposed on the same plane as that of the sensing grating, and outputs sensing light reflected from the sensing grating and reference light reflected from the reference grating. Accordingly, the optical sensor does not require a high-resolution spectroscope and has improved resolution and sensitivity.

An active remote sensing system is provided with an array of laser diodes that generate light directed to an object having one or more optical wavelengths that include at least one near-infrared wavelength between 600 nanometers and 1000 nanometers. One of the laser diodes pulses at a modulation frequency between 10 Megahertz and 1 Gigahertz and has a phase associated with the modulation frequency. A detection system includes a photo-detector, a lens, a spectral filter at an input to the photo-detector, and a processor that processes digitized signals received from the photo-detector to generate an output signal. The detection system uses a lock-in technique that synchronizes pulsing the one laser diode. The active remote sensing system is configured to be mounted on a vehicle or an airborne platform to provide distance information based on a time-of-flight measurement.

A mobile computing device includes an emissive display panel, where the panel is used as a grating, and spectrometer optics positioned behind/below the emissive display panel. A mobile computing device includes an emissive display panel and a spectrometer positioned below the emissive display panel. The emissive display panel includes a first periodic pattern of pixels that include one or more LEDs and a second periodic pattern of circuit elements that control the pixels, where the first and second periodic patterns are configured to diffract light received from outside the device, which passes through the emissive display, and where the diffraction is wavelength-dependent. The spectrometer is configured to detect intensities of different wavelength ranges of the diffracted light.

There is provided a diffractive waveguide device comprising: a light source, at least one light detector, an SBG device comprising a multiplicity of separately switchable SBG elements sandwiched between transparent substrate to which transparent electrodes have been applied. The substrates function as a light guide. Each SBG element encodes image information to be projected on an image surface. Each SBG element when in a diffracting state diffracts light out of the light guide to form an image region on an image surface. The light detector detects light scattered from an object disposed in proximity to the image surface and illuminated by said image region.

The invention relates to a surface refractive index scanning system for characterization of a sample. The system comprises a grating device for holding or receiving the sample, the device comprising at least a first grating region having a first grating width along a transverse direction, and a second grating region having a second grating width in the transverse direction. The first grating region and the second grating region are adjacent in the transverse direction, wherein the first grating region has a grating period Λ.sub.1 in a longitudinal direction, and the second grating region has a grating period Λ.sub.2 in the longitudinal direction, where the longitudinal direction is orthogonal to the transverse direction. A grating period spacing ΔΛ=Λ.sub.1-Λ.sub.2 is finite. Further, the first and second grating periods are chosen to provide optical resonances for light respectively in a first wavelength band and a second wavelength band, light is being emitted, transmitted, or reflected in an out-of-plane direction, wherein the first wavelength band and the second wavelength band are at least partially non-overlapping in wavelength. The system further comprises a light source for illuminating at least a part of the grating device with light at an illumination wavelength band. Additionally, the system comprises an imaging system for imaging the emitted, transmitted or reflected light from the grating device. The imaging system comprises an optical element, such as a cylindrical lens or a bended mirror, configured for focusing light in a transverse direction and for being invariant in an orthogonal transverse direction, the optical element being oriented such that the longitudinal direction of the grating device is oriented to coincide with the invariant direction of the optical element, and an imaging spectrometer comprising an entrance slit having a longitudinal direction oriented to coincide with the invariant direction of the optical element. The imaging spectrometer further comprises a 2-dimensional image sensor. The invention further relates to a method.

There is described a sensor apparatus. It comprises an interrogator comprising a light source emitting pulses having a wavelength about an average wavelength; and a fiber Bragg grating (FBG) arrangement. The arrangement comprises a FBG sensor array comprising a plurality of FBG sensors on an optical fiber and being for reflecting the pulses, thereby producing reflected pulses at each one of the FBG sensors. FBG sensors of a given FBG sensor array have a spatial separation therebetween which is sufficient to allow, at a receiver, a temporal discrimination between the reflected pulses produced by each one of the FBG sensors. The FBG sensor array has a spectral reflection window which comprises the average wavelength.

A projection display device comprising a light source and an SBG device having a multiplicity of separate SBG elements sandwiched between transparent substrates to which transparent electrodes have been applied. The substrates function as a light guide. A least one transparent electrode comprises a plurality of independently switchable transparent electrode elements, each electrode element substantially overlaying a unique SBG element. Each SBG element encodes image information to be projected on an image surface. Light coupled into the light guide undergoes total internal reflection until diffracted out to the light guide by an activated SBG element. The SBG diffracts light out of the light guide to form an image region on an image surface when subjected to an applied voltage via said transparent electrodes.

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.