中文摘要：

作用距离是决定红外成像系统性能的重要指标,可直接影响红外成像光学系统的参数确定。基于作用距离的参数确定方法建立了探测器与作用距离、空间分辨率之间的关系,对光学系统的参数确定和性能评价具有重要作用。结合实例确定了红外成像系统光学的主要参数,采用非制冷凝视型长波红外探测器（工作波段为8μm～12μm）,在特定的作用距离下,利用该方法确定的红外光学系统通光口径为90mm,F数值为1。

英文摘要：

Operating distance is one of the important specifications of an infrared imaging system. It can affect the determination of the parameters for an infrared imaging optical system. Because the parameter determination method based on operating distance has established the relations among a detector, the operating distance and the spacial resolution, it is of importance to the parameter determination and performance evaluation of an optical system. In this paper, the main parameters of a practical infrared imaging system with an uncooled staring long wavelength infrared detector operating in the waveband of 8μm- 12μm are determined. At a particular operating distance, the clear aperture and F number of the infrared optical system are measured to be 90mm and 1 respectively by using this method.