气溶胶对远红外激光辐射的衰减规律研究

计算分析了10.6μm波长远红外激光辐射在不同能见度条件下的大气气溶胶中水平传输的衰减系数、有效传输距离以及斜程传输时的透过率变化规律,对比分析了远红外激光辐射在1.0g/m3的高浓度酸雾和油雾气溶胶中的传输能力。根据Mie理论计算了直径为0.5～40μm的水溶性大气气溶胶和尘状气溶胶粒子对10.6μm激光的散射效率因子、吸收效率因子和消光效率因子。结果表明:气溶胶的消光系数越大、大气能见度越低,大气气溶胶对远红外激光辐射的衰减越严重;在1.0g/m3的高浓度酸雾和油雾气溶胶中远红外激光辐射的有效传输距离只有20～50m。水溶性大气气溶胶和尘状气溶胶粒子对10.6μm激光辐射的衰减机理基本相同,其中散射作用居于主导地位并且平均直径大于5μm的气溶胶粒子对10.6μm远红外激光辐射具有显著的衰减作用。

Study On Attenuation of Aerosol to Far Infrared Laser Emission

The attenuation coefficient and effective distance of 10.6 μm laser emission horizontally transmitted through atmospheric aerosol were calculated under different visibility,the transmittances were calculated too when the laser emission slopingly transmitted through the aerosol.The transmitting performances of the laser were analyzed when transmitted both through acid and oil fog with a concentration of 1.0 g/m3.The scattering,absorption and extinction efficiency factors were calculated according to Mie theory to study the attenuation of water-solubility aerosol and dust particles with diameters between 0.5～40 μm to 10.6 μm laser emission.The results showed that atmospheric aerosol had stronger attenuation to 10.6 μm laser emission when its extinction coefficient was bigger or visibility was smaller.The laser emission effectively transmitted only 20～50 m through the acid and oil fog with a concentration of 1.0 g/m3.The attenuation principles of water-solubility aerosol and dust particles to 10.6 μm laser emission were similar and the attenuation depended upon scattering effect,while the aerosol particle produced stronger attenuation when its diameter was bigger than 5 μm.