A light source may illuminate a scene with pulsed light that is pulsed non-periodically. The scene may include fluorescent material that fluoresces in response to the pulsed light. The pulsed light signal may comprise a maximum length sequence or Gold sequence. A lock-in time-of-flight sensor may take measurements of light returning from the scene. A computer may, for each pixel in the sensor, perform a Discrete Fourier Transform on measurements taken by the pixel, in order to calculate a vector of complex numbers for the pixel. Each complex number in the vector may encode phase and amplitude of incident light at the pixel and may correspond to measurements taken at a given time interval during the pulsed light signal. A computer may, based on phase of the complex numbers for a pixel, calculate fluorescence lifetime and scene depth of a scene point that corresponds to the pixel.

A method and analyser for identifying or verifying or otherwise characterising a sample comprising: using or having an electromagnetic radiation source for emitting electromagnetic radiation in at least one beam at a sample, the electromagnetic radiation comprising at least two different wavelengths, using or having a sample detector that detects affected electromagnetic radiation resulting from the emitted electromagnetic radiation affected by the sample and provides output representing the detected affected radiation, and using or having a processor for determining sample coefficients from the output, and identifying or verifying or otherwise characterising the sample using the sample coefficients and training coefficients determined from training samples, wherein the coefficients reduce sensitivity to a sample retainer variation and/or are independent of concentration.

A system for an EUV light source includes a metrology light source configured to emit a metrology light beam; and an optical beam combiner positioned to receive the metrology light beam and at least one other light beam and to direct the metrology light beam and the at least one other light beam onto a beam path toward a target region. After interacting with the optical beam combiner, the metrology light beam and the at least one other light beam have the same polarization state.

Methods and apparatuses of generating and processing a real-time time-domain cavity ringdown spectroscopy (CRDS) signal from absorbing species in an optical detection system having an optical ringdown cavity using off-axis paths are provided. At least one modulated light signal is generated using one or more light sources, each modulated at specified modulation frequency. Each modulated signal has harmonic frequency components and is input off-axis relative to the cavity's optical axis. The cavity contains mirrors arranged in a predetermined configuration. The optical axis is defined by a path passing through centers of mirrors. The modulated light signal is resonated off axis without astigmatic optical elements to produce CRDS signal and passes at least twice through cavity and across the mirrors without interfering with itself. An overall path length through cavity is greater than path length of optical axis. A photodetector detects the CRDS signal, which is demodulated dependent upon selected harmonics.

Provided is a fluorescence image acquisition apparatus for acquiring fluorescence images and phase images using optical signals that are modulated at the same frequency and that have different time delays. The fluorescence image acquisition apparatus may include a light source configured to generate, at different time delays, a plurality of optical signals that are modulated at the same frequency, an illuminator configured to control paths of the plurality of modulated optical signals so that the plurality of modulated optical signals are illuminated onto a sample including a plurality of fluorescent materials, a photodetector configured to detect a plurality of fluorescence signals that are emitted from the plurality of fluorescent materials, respectively, and a controller configured to acquire a plurality of fluorescence images and a plurality of phase images from the plurality of detected fluorescence signals.

A modular testing device includes a base unit and an expansion unit that communicates with the base unit. The expansion unit includes a housing, a receptacle in which a sample holder containing a biological sample and reagent mixture can be placed, and an optical assembly positioned in the housing. The optical assembly is configured to amplify and detect a signal from the biological sample and reagent mixture. Data that is collected in the optical assembly is communicated to the base unit.

A photoacoustic gas analyzer may include: a gas chamber configured to receive a gas to be analyzed therein, a radiation source configured to emit into the gas chamber electromagnetic radiation with a time-varying intensity adapted to selectively excite gas molecules of N mutually different gas types the concentrations of which are to be determined in the gas received in the gas chamber, thereby generating acoustic waves, an acoustic-wave sensor configured to detect acoustic waves generated by the electromagnetic radiation emitted by the radiation source into the gas to be analyzed, and a control unit operatively connected to the radiation source and the acoustic-wave sensor. The control unit may be configured: to control the radiation source to emit electromagnetic radiation with a time-varying intensity and to modulate the frequency at which the intensity is varied with a modulation signal taking on at least N mutually different values, to receive from the acoustic-wave sensor signals indicative of detected acoustic waves generated by the electromagnetic radiation emitted by the radiation source into the gas to be analyzed, to determine at least N mutually different signal amplitudes associated with respective N mutually different frequencies at which the intensity of the emitted electromagnetic radiation is varied, and to determine from the determined signal amplitudes the concentrations of the N mutually different gas types.

A hand held spectrometer is used to illuminate the object and measure the one or more spectra. The spectral data of the object can be used to determine one or more attributes of the object. In many embodiments, the spectrometer is coupled to a database of spectral information that can be used to determine the attributes of the object. The spectrometer system may comprise a hand held communication device coupled to a spectrometer, in which the user can input and receive data related to the measured object with the hand held communication device. The embodiments disclosed herein allow many users to share object data with many people, in order to provide many people with actionable intelligence in response to spectral data.

An electrically modulated light source comprises a carbon nanotube-graphene composite film structure, a first electrode and a second electrode. The carbon nanotube-graphene composite film structure comprises a carbon nanotube layer and a graphene layer stacked with each other. The first electrode and the second electrode electrically coupled with nanotube-graphene composite film structure. The first electrode and the second electrode are configured to apply a voltage to the carbon nanotube-graphene composite film structure.

A hand held spectrometer is used to illuminate the object and measure the one or more spectra. The spectral data of the object can be used to determine one or more attributes of the object. In many embodiments, the spectrometer is coupled to a database of spectral information that can be used to determine the attributes of the object. The spectrometer system may comprise a hand held communication device coupled to a spectrometer, in which the user can input and receive data related to the measured object with the hand held communication device. The embodiments disclosed herein allow many users to share object data with many people, in order to provide many people with actionable intelligence in response to spectral data.