35 results about "Spectral signal-to-noise ratio" patented technology

The invention relates to a method and apparatus of infrared modulation photo-induced luminous spectrum based on step scan. The apparatus comprises a Fourier transform infrared spectrograph measuring system, a laser used as active light source, a lock-in amplifier which connects the Fourier transform infrared spectrograph detector and the circuit controlling plate and a circuit-breaker on the light path between the sample and the laser, so that it can transfer the constant active light into the modulated active light and feedback it in the reference end of the lock-in amplifier to control the lock-in.

The invention discloses a device for improving the signal to noise ratio of the blood absorption spectrum and a control method thereof. An oversleeve is connected respectively with an air pump and an air release valve through an air tube. The air pump pressurizes the sleeve through the air tube and deflates the sleeve through the air release valve. An import optical signal module and an export optical signal module are arranged at positions opposite to each other at the bottom of the nail of a finger. The import optical signal module is arranged upward and the export optical signal module is arranged downward. A data collecting module is respectively connected with the import optical signal module and the export optical signal module to collect a photoelectrical signal in a normal filling level and a photoelectrical signal in an enhanced filling level. The oversleeve is put on the upper end of the tested arm. The import optical signal module imports detection light and the export optical signal module exports an optical signal to obtain the difference of the photoelectrical signal and obtain the blood absorption spectrum with high signal to noise ratio according to the difference of the photoelectrical signal. The invention solves the problem of insufficient filling, obtains the ideal photoelectrical signal and improves the strength and the noise ratio of blood absorption spectrum.

The invention discloses a LIBS active-passive dual-mode spectrum detection method, which comprises four steps of self-focus realization, LIBS active spectrum detection, infrared passive spectrum detection and active-passive spectrum analysis. The beneficial effect of the present invention is that the internal structure of the spectrometer is optimized by using ingenious electromechanical switching and grating area splitting, and the compactness and convenience of the system are improved; the same spectrometer and the same optical fiber inlet realize the compounding of LIBS active spectrum and infrared passive spectrum Detection, improve detection efficiency; according to different active and passive spectral characteristics, different designs are adopted at the sensor end to achieve targeted spectral detection, improve LIBS active spectral resolution and infrared passive spectral signal-to-noise ratio.

The invention relates to a tuning window-scanning spectral imaging system for a light filter and a tuning window-scanning spectral imaging method for the light filter, and belongs to the field of spectral imaging. The invention is to add a scanning system into a tuning static spectral imaging system for the light filter to make the tuning window-scanning spectral imaging system capable of performing dynamic window-scanning imaging. Moreover, the invention adopts a data acquisition processing system which is matched with the scanning system to make the tuning window-scanning spectral imaging system be capable of completing data processing in the mode of window scanning and output correct spectral cubical result. The invention has high utilization rate of light energy, high spectral resolution and flexible and adjustable service band of spectrums, has both the image signal-to-noise ratio and the spectrum signal-to-noise ratio easy to reach high level, can only be operated in interested wavebands, reduces the data quantity, increases the regulating range of the integral time, can improve the detection level of weak signals, and is suitable to be widely applied in the fields of agricultural production, resource exploration, environmental monitoring, disaster prevention and reduction, substance identification, public safety and the like.

The invention discloses an air pollution composition inversion method based on the ultraviolet-visible hyperspectrum of the Gaofen-5 satellite. Through the inversion calculation of the ultraviolet-visible hyperspectrum of the Gaofen-5 satellite, the column concentration of the air pollution composition can be accurately obtained , so as to achieve continuous and effective observation of air pollution components in a wide range and for a long time. In addition, according to the characteristics and spectral characteristics of the GF-5 instrument, the secondary calibration of the spectrum under the condition of low spectral signal-to-noise ratio and poor stability can be realized, thereby improving the inversion accuracy.

The invention discloses an active and passive dual-mode spectrum detection method, which comprises three steps of active spectrum detection, passive spectrum detection and active and passive spectrum analysis. The beneficial effect of the present invention is that the optimization of the internal structure of the spectrometer is realized by adopting ingenious electromechanical switching and grating area splitting, and the compactness and convenience of the system are improved; the same spectrometer and the same optical fiber inlet realize the composite detection of active and passive spectra, and improve the detection efficiency. Efficiency: According to the different characteristics of active and passive spectra, different designs are adopted at the sensor end to achieve targeted spectral detection, improve active spectral resolution and passive spectral signal-to-noise ratio.