Study On Influence Of Wavelength Of Downhole TV Lighting Source On System Mechanism

Downhole TV visual logging technology,as a logging technology widely used in recent years,takes advantage of the characteristics of human visual cognition system,and uses surface array sensors(cameras,cameras)to obtain high-definition smooth well video.Efficient.The speciality of the oil well shaft environment makes it necessary to complete the preparation of the clean water circulation well washing and to provide a stable and reliable illumination source.The lack of both will affect the overall imaging quality of the system.Therefore,on the basis of clear understanding,how to better adapt to the complex well conditions in the underground has become an important research direction of this technology.Based on the existing logging equipment,this paper studies the influence of the wavelength of the illumination source on the downhole TV system,thereby improving the imaging quality of the equipment and enhancing the environmental adaptability of the equipment.The specific contents include:(1)analyzing the composition of the replacement liquid after washing,and studying the spectral characteristics of the visible light source in the replacement liquid.The linear relationship between the wavelength of the light source and the absorption coefficient of water,the scattering coefficient and the beam expansion factor is analyzed,and a monochromatic light source of the optimal wavelength(520 nm)is selected as the system illumination source.(2)Analyze the functional requirements of the downhole TV lighting system,select the appropriate microprocessor,light source drive and communication mode,complete the hardware circuit schematic and PCB design and the software design of the overall control part of the lighting system..(3)Collecting replacement fluids for different oil wells in different regions,using visible light sources and monochromatic light sources of selected wavelengths as illumination sources,and five sets of image data.(4)In order to further verify the influence of the wavelength of the light source on the downhole TV,a variety of related image quality evaluation methods are studied.Based on the MSE,PSNR and SSIM algorithm models,the image quality evaluationprogram was written by means of MATLAB tools,and the five groups of image data were processed and analyzed.Through a large number of theoretical studies and basic experimental tests,determining the source illumination system of selected wavelengths can improve the imaging quality of imaging equipment,and to some extent fill the gap in the research direction of downhole TV light sources.