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 image sensor assembly includes at least one upconverter configured to detect light in a NIR waveband that is received from an object to be imaged and generate, based on the detected light, upconverted light that is outside of the NIR waveband; and at least one image sensor configured to detect the upconverted light.

Example embodiments relate to imaging systems and methods for acquisition of multi-spectral images. One example imaging system includes a detector that includes an array of light sensitive elements arranged in rows and columns. Each light sensitive element is configured to generate a signal dependent on an intensity of light incident onto the light sensitive element. The imaging system also includes a plurality of wavelength separating units. Each wavelength separating unit is configured to spatially separate incident light within a wavelength range into a number of wavelength bands distributed along a line. The line is a straight line. Each wavelength band along the line is associated with a mutually unique light sensitive element. Further, the imaging system includes a processing unit configured to define a number of mutually unique clusters of light sensitive elements for summing signals from the light sensitive elements within the respective clusters.

The invention relates to a handheld device and method for determining a status of a plant. The device includes a multi pixel digital colour sensor, a light source arranged for providing broadband illumination, wherein the light source and the multi pixel digital colour sensor are arranged in substantially the same plane, a light guide for guiding the light from said light source into the direction of the multi pixel digital colour sensor, a sample space, provided between the multi pixel digital colour sensor and the light source, for insertion of at least a part of the plant therein, and a processing unit configured for controlling at least the multi pixel digital colour sensor and the light source.

An on-chip interferometer and a spectrometer including the interferometer are provided. An on-chip interferometer includes a waveguide for propagation of an optical signal including an input waveguide; at least two interferometer arms having one or more slot waveguides; and an output waveguide; wherein the input waveguide is split into the at least two interferometer arms which are recombined into the output waveguide; and a control mechanism configured for controlling a relative time delay between optical signals propagating in the two interferometer arms by modifying one or more slot widths of one or more of the slot waveguides; and wherein the relative time delay is at least 1, 2, 5, or at least 10 fs or at least one optical period of the longest optical wavelength of the optical signal.

A handheld spectrometer can be configured with a visible aiming beam to allow the user to determine the measured region of the object. When the visible aiming beam comprises the spectrometer measurement beam, the spectrometer measurement beam comprises sufficient energy for the user to see the measurement beam illuminating the object. When the visible aiming beam comprises a separate beam, the visible aiming beam comprises sufficient energy for the user to see a portion of the aiming beam reflected from the object. The visible aiming beam and measurement beam can be arranged to at least partially overlap on the sample, such that the user has an indication of the area of the sample being measured.

A system includes a first spectral modulator, a second spectral modulator, a light guide optically, a photodetector, and an electronic control device. The first spectral modulator receives sample light, and modulates the sample light according to a first spectral response pattern to produce first modulated light. The second spectral modulator receives the first modulated light from the first spectral modulator via the light guide, modulates the first modulated light according to a second spectral response pattern to produce second modulated light, and transmits the second modulated light to the photodetector. The photodetector measures an intensity of the second modulated light incident on the photodetector, and generates one or more signals corresponding to the intensity of the second modulated light. The electronic control device determines a spectral distribution of the sample light based on the one or more signals.

In a spectroscopic module, a light shielding member is disposed between a plurality of bandpass filters and a light detector. The light shielding member includes a plurality of wall portions. The plurality of wall portions are arranged along an X direction with a light passage opening interposed therebetween, each of a plurality of optical paths from the plurality of bandpass filters to a plurality of light receiving regions passing through the light passage opening. A first wall portion and a second wall portion adjacent to each other among the plurality of wall portions are in contact with the bandpass filter, the bandpass filter corresponding to the light passage opening between the first wall portion and the second wall portion. A width in a Y direction of the light passage opening is larger than a width in the Y direction of the bandpass filter.

The present disclosure is directed to irradiance sensing devices and methods. One such device includes a housing and an optical diffuser coupled to the housing. The housing has an opening that extends into the housing from an outer surface, and the opening has a circular shape at the outer surface of the housing. The optical diffuser has a first region that extends at least partially beyond the outer surface of the housing and a second region housed within the housing. The first region of the optical diffuser has a curved surface, and the optical diffuser includes a cavity extending at least partially into the second region.

An IR radiator element (1) suitable for use as a miniature infrared emitter (micro-hotplate) in a gas sensor, IR-spectrometer or electron microscope. The micro-hotplate comprises a plate (2) supported by multiple support arms (4). The plate and arms are fabricated as a MEMS device comprising a single contiguous piece of electrically-conducting refractory ceramic such as hafnium carbide (HfC) or tantalum hafnium carbide (TaHfC). Each of the arms (4), in addition to providing structural cantilever support for the plate (2), acts as a heating element for the plate (2). The plate (2) is heated by applying a voltage across the arms (4). The arms (4) may also be shaped to absorb thermomechanical stress which arises during the heating and cooling of the arms and plate. The plate, which may have an area of less than 0.05 mm.sup.2 and a thickness of between 1% and 10% of the largest dimension of the plate (2), for example, can be heated to 4,000 K or more and cooled again with a duty cycle of as little 0.5 ms, thereby permitting pulsed operation at frequencies of up to 2 kHz. Its small size (10-200 μm) and low power consumption (e.g. 10-100 mW) make the micro-hotplate suitable for use in cryogenic applications, in miniaturized devices or in battery-powered devices such as mobile phones.