CAJ | 학술논문

双光路能见度测量系统是一种基于 CCD（Charge-Coupled Device）数字摄像和光在大气中衰减理论的能见度测量系统，首先设置远、近两个固定距离的特性相同的目标光源和背景装置，然后通过 CCD 拍摄所设置的目标光源和背景，拍摄的图像由1394数据线和图像采集卡传输到计算机，通过数字图像处理获取目标光源和背景的灰度信息，最终利用相应的算法计算能见度。试验表明：双光路能见度测量系统和透射式能见度仪对比偏差随能见度的升高而升高，而与前向散射式能见度仪对比偏差随能见度的升高有小幅降低，通过白天和夜晚数据对比可知，白天太阳光的影响已基本消除。
쌍광로능견도측량계통시일충기우 CCD（Charge-Coupled Device）수자섭상화광재대기중쇠감이론적능견도측량계통，수선설치원、근량개고정거리적특성상동적목표광원화배경장치，연후통과 CCD 박섭소설치적목표광원화배경，박섭적도상유1394수거선화도상채집잡전수도계산궤，통과수자도상처리획취목표광원화배경적회도신식，최종이용상응적산법계산능견도。시험표명：쌍광로능견도측량계통화투사식능견도의대비편차수능견도적승고이승고，이여전향산사식능견도의대비편차수능견도적승고유소폭강저，통과백천화야만수거대비가지，백천태양광적영향이기본소제。
Dual optical path visibility system is a visibility measuring system based on a charge coupled device (CCD)digital camera and a light attenuation theory in atmosphere.Photovoltaic conversion process is real-ized by using the CCD to measure the light attenuation in the atmosphere.Two target reflection and back-ground devices at different fixed distances are installed in the dual optical path visibility system and have i-dentical characteristics except for distances.During measurement,a light source and the CCD are arranged at the same place,light signal sent by the light source is transmitted to the target reflector and reflected back,two beams of light reflected back are received by the CCD,the CCD converted reflected beams of light to corresponding facula images,and the whole photovoltaic conversion process is completed.Com-pared with the traditional digital camera method in which the same distance between a CCD and a target de-vice is set,the light path distance of the dual optical path visibility system is doubled because of light re-flection.The facula images captured by the CCD are transmitted to a computer and the attenuation infor-mation and background grey information of target facula images are acquired by digital image processing. The center of gravity method is used to dynamically extract the attenuation information of the target facula images,random noise is eliminated by averaging a plurality of extracted facula images,and the attenuation information is used for visibility back calculating.A back calculation formula is derived based on the classi-cal optical attenuation theory,the formula is improved by combining an actual experimental platform,and finally,visibility is calculated.Through contrast experiments and correlation coefficients,the basic trend of visibility data of the dual optical path visibility system is consistent with that of the traditional transmis-sion visibility meter and the traditional forward scatter visibility meter,especially when the visibility is low,and with the visibility increasing,the trend consistency declines to some extent.According to the mean deviation and mean relative deviation,visibility data of the dual optical path visibility system are more close to the traditional transmission visibility meter because of a similar working principle,as the du-al optical path visibility system and the traditional transmission visibility measure attenuation of a whole light path while the forward scatter visibility meter only measures atmospheric scattering.With the visibil-ity increasing,the visibility data deviation of the dual optical path visibility system and the traditional transmission visibility meter become larger mainly because of more fluctuation.In addition,optical axis a-lignment of the traditional transmission visibility meter is required and the camera lens of the traditional transmission visibility meter is sensitive to contaminant.Through visibility data comparison of day and night,it is observed that sunlight influences on the visibility data are basically eliminated.