The Design Of Spectrum’s Acquisition System Based On ARM7

In recent decades, the spectrum analysis technology and the spectrum analysis instrument is increasingly becoming the essential spectrum analysis tools in the industrial development, academic research and other areas. With the rapid development and popularization of computers and electronic devices, the traditional analog signal spectrum analysis instrument has been difficult to meet the accuracy and efficiency requirements of people’s increasing demands for data, it is now a major development direction of the spectroscopic instruments is accurate and fast.The spectrum acquisition system mentioned in this issue used the linear array CCD as the herein photoelectric sensor. This system communicate with the computer by an ARM7 circuitry, and the system allow a real-time and efficient light source spectral data acquisition system.This acquisition system includes three parts which will be explained. The first part is the hardware circuit. It uses LPC2138 as the main controller, which controls the timing-driven of the linear array CCD chip ILX554 B and the High-speed AD conversion chip AD9826. The main contents of the hardware portion includes: A/D converting circuit, controlling circuit, USB interface circuit, power circuit and the design of corresponding timing-driven and firmware. The second part is the software design. This part mainly include the design of the USB drivers and the computer applications, which achieve the real-time collecting and drawing the the collected spectral curve in a graphical interface operation. The device can work properly under the control of the program. The CCD can be driven by the circuit and collect the data from the incident light source and the whole device can collect the correct spectrum data and complete information transmission with the host computer efficiently. The third part is the analization of this detecting system. This paper uses the MATLAB to finish the wavelength calibration of the spectral curve, designs scheme of noise reduction filtering, and analyzes the causes and sources of the systematic error.The spectrum acquisition system mentioned in this paper has being practically testing, and it can work stablely. Compared to the traditional spectral analysis instrument, this spectrum acquisition system has great advantages on the data transmission efficiency, accuracy, power and scalability, and the measurable wavelength range up to 353.47 nm 795.37 nm. The measurable wavelength can meet the the needs of the range of visible light acquisition. Besides, it has maintained a sufficient miniaturization on the design of the optical front-end and circuit, cost-effective demand, so compared to conventional spectrometers, this device has obvious advantages on the volume and cost.