According to an example aspect of the present invention, there is provided a method for analysing a chemical composition of a target, the method comprising placing an electrically tunable Fabry-Perot interferometer in a path of radiation emitted by a radiation source, and detecting the radiation, which has passed the Fabry-Perot interferometer and which has passed or was reflected by the target, by means of a detector, and wherein detection is made such that multiple pass bands are allowed to be detected simultaneously.

Measurement apparatus including an optical sensor, which performs repeatedly transmission measurements through moving sheet of paper or board at at least one wavelength band dominantly absorbed by water, at at least one wavelength band dominantly absorbed by cellulose. The apparatus also includes an X-ray sensor, which performs repeatedly transmission measurements through the moving sheet of paper or board with photons of electromagnetic radiation (1 keV to 10 keV). The apparatus comprises a data processing unit, which receives signals with information on intensities of the optical and X-ray radiations passed through the sheet from the optical sensor and the X-ray sensor, and determines, based on the information, all of the following of the moving sheet: the dry stuff content as a function of the cellulose mass per unit area of the sheet, water mass per unit area of the sheet and the ash mass per unit area of the sheet.

The disclosure provides an apparatus, a device, and methods for improving optical analysis of a thin layer of a sample between two plates, particularly for multiple wavelengths.

A surgical visualization feedback system is disclosed. The surgical visualization feedback system comprises an emitter assembly configured to emit electromagnetic radiation toward an anatomical structure. The emitter assembly comprises a structured light emitter configured to emit a structured light pattern on a surface of the anatomical structure and a spectral light emitter configured to emit spectral light capable of penetrating the anatomical structure. The surgical visualization feedback system further comprises a waveform sensor assembly configured to detect reflected electromagnetic radiation corresponding to the emitted electromagnetic radiation and a control circuit in signal communication with the waveform sensor assembly. The control circuit is configured to receive an input corresponding to a selected surgical procedure, determine an identity of a targeted structure within the anatomical structure based on the selected surgical procedure and the reflected electromagnetic radiation, and confirm the determined identity of the targeted structure through a user input.

The embodiment of the present application relates to the field of substance ingredient detection, for example, relates to a substance ingredient detection method and apparatus, and a detection device. The method includes: obtaining spectral information of a substance to be detected; and matching the spectral information with a pre-obtained prediction model based on a machine learning algorithm to obtain the ingredients of the substance to be detected. In the embodiment of the present application, the spectral information of the substance to be detected is obtained, and then the spectral information is matched with the prediction model based on the machine learning algorithm to obtain the prediction result of the ingredients of the substance to be detected. In the embodiment of the present application, the machine learning algorithm is combined with spectral recognition, the traditional algorithm is abandoned, the recognition speed is improved, and the substance detection efficiency is greatly improved.

A surgical suturing tracking system is disclosed. The surgical suturing tracking system is configured to detect and guide a suturing needle during a surgical suturing procedure. The surgical suturing track system comprises a control circuit configured to predict a path of a needle suturing stroke after receiving an input from a clinician, detect an embedded tissue structure, and assess proximity of the predicted path and the detected embedded tissue structure.

Measurement apparatus including an optical sensor, which performs repeatedly transmission measurements through moving sheet of paper or board at at least one wavelength band dominantly absorbed by water, at at least one wavelength band dominantly absorbed by cellulose. The apparatus also includes an X-ray sensor, which performs repeatedly transmission measurements through the moving sheet of paper or board with photons of electromagnetic radiation (1 keV to 10 keV). The apparatus comprises a data processing unit, which receives signals with information on intensities of the optical and X-ray radiations passed through the sheet from the optical sensor and the X-ray sensor, and determines, based on the information, all of the following of the moving sheet: the dry stuff content as a function of the cellulose mass per unit area of the sheet, water mass per unit area of the sheet and the ash mass per unit area of the sheet.

A concentration calculation system calculates a concentration of the optically active substance based on a formula. The formula includes a first function representing wavelength dependence of an optical rotation of a first optically-active substance, and a second function representing wavelength dependence of an optical rotation of a second optically-active substance. In the first function, concentration of the first optically-active substance has an unknown value, and an inherent value for defining a characteristic of optical rotatory dispersion of the first optically-active substance is a known value or an unknown value within a certain limited range. In the second function, an inherent value for defining a characteristic of optical rotatory dispersion of the second optically-active substance is an unknown value. The concentration of the first optically-active substance is calculated based on the formula and optical rotations of measurement target respectively corresponding to a plurality of wavelengths, by using a least-squares method.

Methods, apparatuses and systems for detecting multiple gaseous substances for detecting a plurality of target gaseous substances or chemical compositions, using, for example, a high-speed, tunable gas detecting apparatus. An example gas detecting apparatus may comprise: a light source configured to generate a light beam, a moveable mirror component configured to move between a plurality of positions, wherein each position of the moveable mirror component is associated with a narrow band corresponding with a gas absorption frequency range of a target gaseous substance or chemical composition, at least one optical component configured to condition an output light beam of the moveable mirror component, wherein a measurable attenuated optical signal is generated responsive to exposing a sample gaseous substance to the conditioned output light beam.

A highly sensitive trace gas sensor based on a Fabry-Perot semiconductor laser and cavity enhanced absorption spectroscopy is designed to be capable of measuring sub-ppb concentrations of trace gases in real time. The broad frequency range of the multi-mode Fabry-Perot semiconductor laser spans a large number of absorption lines of the species of interest enabling multiple line integrated absorption spectroscopy which improves the sensitivity of detection. Additionally, the broad wavelength range of the laser excites a large number of cavity modes simultaneously, thereby reducing the sensor's susceptibility to vibration and thermal fluctuations making it suitable for field based monitoring applications. Using a high finesse optical cavity also enhances the sensitivity of the sensor by providing large path lengths, on the order of kilometers, in a small volume. Relatively high laser power is used to compensate for the low coupling efficiency of a broad linewidth laser to the optical cavity.