The CCD is widely used to detect laser signal in many industrial vision and automation systems. When the charge coupled device(CCD) is irradiated by intense laser, the image quality may decrease and reversible dazzling effects occur such as single pixel saturation, crosstalk, and full saturation. Understanding the laser dazzling phenomena, on the one hand, it can help to choose the suitable laser sources for the measuring systems, on the other hand, it can optimize the designs of the CCD structures. In order to effectively utilize the dazzling effects, the laser saturation threshold of the CCD must be known. Due to the different internal structure and working mode of CCD, the corresponding laser saturation threshold is also different. In this paper, the dazzling effects on the array CCD induced by a 532nm wavelength pulsed laser is investigated by finite element method. A physical model is established base on drift-diffusion equation according to the working process of CCD and the principle of laser dazzling effects. The working state of CCD under different laser power, charge density, electron concentration and potential curve are presented. This model is found to be useful for the analysis of laser saturation threshold.
Based on tunable diode laser absorption spectroscopy (TDLAS), the tomography is used to reconstruct the combustion gas temperature distribution. The effects of number of rays, number of grids, and spacing of rays on the temperature reconstruction results for parallel ray are researched. The reconstruction quality is proportional to the ray number. The quality tends to be smoother when the ray number exceeds a certain value. The best quality is achieved when η is between 0.5 and 1. A virtual ray method combined with the reconstruction algorithms is tested. It is found that virtual ray method is effective to improve the accuracy of reconstruction results, compared with the original method. The linear interpolation method and cubic spline interpolation method, are used to improve the calculation accuracy of virtual ray absorption value. According to the calculation results, cubic spline interpolation is better. Moreover, the temperature distribution of a TBCC combustion chamber is used to validate those conclusions.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.