The invention relates to an apparatus and a method for evaluating spectral properties of a measurement object. It comprises a plurality of light emission units, each emitting light with a predetermined emission spectrum and having a respective output configured for emitting the light with the predetermined emission spectrum onto the measurement object, an optical spectrograph having an input port adapted to receive light from the measurement object and a diffraction unit adapted to distribute different wavelengths of the received light to different output ports comprising the optical detectors, wherein the diffraction unit is adapted to distribute said received light to the respective output ports such that the lights in the respective output port have different wavelengths at different diffraction orders; a signal identification unit adapted to identify which of the light emission units contribute to the respective light in the respective output ports.

The present disclosure is directed to a method of forming a polarization grating structure (e.g., polarizer) as part of a grid structure of a back side illuminated image sensor device. For example, the method includes forming a layer stack over a semiconductor layer with radiation-sensing regions. Further, the method includes forming grating elements of one or more polarization grating structures within a grid structure, where forming the grating elements includes (i) etching the layer stack to form the grid structure and (ii) etching the layer stack to form grating elements oriented to a polarization angle.

The disclosure relates to an optical characteristic measurement system including at least: a light source unit which outputs an input beam of a specific wavelength; a sensing unit which generates a signal beam by using a sensor whose optical characteristic is affected by an external environment condition; and a measuring unit which derives varied physical amount by using the signal beam delivered from the sensing unit, wherein the measuring unit includes: an optical coupler which distributes the signal beam into the two optical paths; and an interrogation optical fiber which is arranged on one of the paths on which the signal beam travels. The interrogation optical fiber has a linear light absorption characteristic in the specific wavelength range, and the light intensity of the signal beam is measured to detect a wavelength of the signal beam delivered from the sensing unit, and finally derive the physical amount applied from outside.

A spectrometer includes an input unit for receiving an optical signal, a diffraction grating disposed on the transmission path of the optical signal for dispersing the optical signal into a plurality of spectral rays, an image sensor disposed on the transmission path of at least a portion of the spectral rays, and a waveguide device. A waveguide space is formed between the first and second reflective surfaces of the waveguide device. The optical signal is transmitted from the input unit to the diffraction grating via the waveguide space. The portion of the spectral rays is transmitted to the image sensor via the waveguide space. At least one opening is formed on the waveguide device, and is substantially parallel to the first and/or second reflective surface. A portion of the spectral rays and/or the optical signal diffuses from the opening out of the waveguide space without reaching the image sensor.

An apparatus for measuring time-resolved optical spectrum includes a light source, a sensor for collecting, forming, manipulating and measuring the intensity of the optical radiation, and a controller coupled to the light source and sensor. The sensor includes at least one optical delay element to provide a time delay to a first portion of the optical radiation. The sensor arrangement further includes an optical spectral disperser to split the delayed first portion and the second portion of the optical radiation into dispersed radiation having a plurality of wavelengths, and a sensor element configured to receive each wavelength of the dispersed radiation on a different spatial region, and measure the light intensity associated with each wavelength of the dispersed radiation. The controller collects the light intensity associated with each wavelength of the dispersed radiation measured by the sensor element to form a time-resolved optical spectrum.

When implementing a PMU network, creation of synchrophasors is achieved by centralising the determining of phasors and corresponding time-stamps at a location away from the actual measurement locations. Alternatively, or in addition to time-stamping phasors, time-stamping of any received signals and/or measurements derived from those signals is enabled. These signals are received from appropriate sensors distributed along optical fibres such as may be incorporated in modern power cables. Likewise, control signals can be communicated along optical fibres such as may be incorporated in modern power cables, and a number of approaches to ensuring control signals are received by the intended control modules are provided. Either or both the PMU network and control system can be implemented in a power network by exploiting existing optical fibre infrastructure in this way, and control signals can be transmitted dependent on analysis performed on synchrophasors.

Provided are a dual coupler device configured to receive lights of different polarization components, a spectrometer including the dual coupler device, and a non-invasive biometric sensor including the spectrometer. The dual coupler device may include, for example, a first coupler layer configured to receive a light of a first polarization component among incident lights. and a second coupler layer configured to receive a light of a second polarization component among the incident lights, wherein a polarization direction of the light of the first polarization component is perpendicular to a polarization direction of the light of the second polarization component. The first coupler layer and the second coupler layer may be spaced apart from each other and extended along a direction in which the light propagates in the first coupler layer and the second coupler layer.

An example embodiment relates to a photonic integrated circuit device and a method for its manufacture. An example device includes a planar detector having at least one photodetector. The device may further include a waveguide layer arranged substantially parallel to the planar detector, the waveguide layer including a first integrated waveguide for guiding a first light signal. A cavity may be formed in the waveguide layer in a region spaced away from the edges of the waveguide layer such as to terminate the first integrated waveguide in that region. A first reflective surface may be provided in the cavity to reflect the first light signal guided by the first integrated waveguide toward a first photodetector of the planar detector.

The invention relates to an apparatus and a method for evaluating spectral properties of a measurement object. It comprises a plurality of light emission units, each emitting light with a predetermined emission spectrum and having a respective output configured for emitting the light with the predetermined emission spectrum onto the measurement object, an optical spectrograph having an input port adapted to receive light from the measurement object and a diffraction unit adapted to distribute different wavelengths of the received light to different output ports comprising the optical detectors, wherein the diffraction unit is adapted to distribute said received light to the respective output ports such that the lights in the respective output port have different wavelengths at different diffraction orders; a signal identification unit adapted to identify which of the light emission units contribute to the respective light in the respective output ports.

Various embodiments provide an optical sensor having an optical source, a grating arrangement optically coupled to the optical source to receive a source optical signal from the optical source, the grating arrangement including a chirped FBG having a defined spectral profile, wherein, in response to a first change in at least one parameter interacting with the chirped FBG, the defined spectral profile is shifted in a first direction relative to a reference spectral profile, and the grating arrangement is configured, in response thereto, to generate a first output optical signal corresponding to the first change, and wherein, in response to a second change in the at least one parameter interacting with the chirped FBG, the defined spectral profile is shifted in a second direction relative to the reference spectral profile, and the grating arrangement is configured, in response thereto, to generate a second output optical signal corresponding to the second change.