Design Of Data Acquisition System For Micro Spectrometer

The data acquisition system is an important part of the miniature spectrometer,which determines the performance indicators such as the size and cost of the miniature spectrometer.CCD and CMOS image sensors are two types of detectors commonly used in micro-spectrometer data acquisition systems.They are used to collect light and use the photoelectric effect to convert optical signals into electrical signals.It is one of the most important parts of data acquisition systems.In this paper,a quality linear array CMOS image sensor S11639-01 from Hamamatsu is used as the detector of the data acquisition system,and a compact micro-spectrometer data acquisition system is designed.The drive of the image sensor and the control of the data acquisition system all use the 32-bit processing STM32H743 chip of the ARM Cortex-M7 core.The data conversion adopts the 16-bit medium and high speed analog-to-digital converter built in the STM32 chip,and the data transmission adopts the universal serial bus(USB)module built in the STM32 chip,and at the same time supplies power to the system through the USB interface.Therefore,the data acquisition system has the characteristics of compact structure,small size,light weight and good portability.In terms of experiments,first,the circuit performance of the data acquisition system is tested with reference to the detection optical path.The detection optical path is composed of an attenuator,an optical power meter,and a semi-transparent mirror.The light sources are three stable laser sources with fixed wavelengths.After testing,the circuit system has the characteristics of small random error,high linearity(voltage-light intensity,voltage-integrationtime),good pixel uniformity,and accurate wavelength response.Then,an optical path system consisting of an incident slit and a flat-field concave grating was constructed.The standard spectrometer low-pressure mercury argon lamp and standard tungsten halogen light source were used to perform a spectral test on the miniature spectrometer composed of a data acquisition system and an optical path system.Spectral data processing(wavelength calibration,spectrum automatic peak search).After testing,the performance of the data acquisition system has the characteristics of high resolution,real-time transmission,high linearity(voltage-integration time),and high accuracy.