讨论了折射/衍射红外鱼眼镜头的设计.设计出工作波段为8~12 μm,全视场为240°的折衍混合的红外鱼眼镜头光学系统.采用反远距结构,能够很好地解决超广角镜头的轴外像差和边缘像面照度问题.结果表明：系统结构简单,体积很小、后工作距离大,成像质量好,在截止频率11 lp/mm处的调制传递函数值大于0.5.

The optical design and properties of fish-eye lens are discussed.A refractive/diffractive IR fisheye lens optical system is presented,whose operating wavelength range is 8 to12 μm,and full field of view is up to 240°. The structure of optical system is reversed telephoto lens, and this type of hyper-wide angle lens can balance the off-axis aberrations against the evenness of marginal image illuminance at its image plane very wel1. The results show that the system has the advantages of simplicity,compactness and long back working distance.Its imaging quality is very well,so that its modulated transferfunction value is higher than 0.5 when cutoff frequency at the 11 lines/mm.