提出了一种多波长红外激光二极管的封装结构，为了提高该二极管输出的860、905、1064 nm(脉冲/单模)等多种波长激光光束的平行性，对该封装结构下几种光束的准直技术展开研究。通过对高斯光束在傍轴、离轴两种状态下的成像分析，总结并提出了一种“准共轴”激光光束的成像理论，在该理论基础上设计了多波长激光二极管的准直光学系统，并通过光学设计软件建立了相应的光路模型。在该光路模型指导下制备了多波长激光光源样机，并通过实验对该样机输出的“准共轴”光束的平行性进行验证。实验结果表明，该样机体积小、质量轻，其输出的“准共轴”光束覆盖了860、905、1064 nm(脉冲/单模)等多种波长，并具备良好的平行性。

We present a packaging structure of multi-wavelength infrared laser diode and study the beams collimation techniques under this structure for improving beams parallelism of wavelengths at 860 nm, 905 nm and 1064 nm (pulse/single). By the imaging analysis of Gaussian beam in both paraxial and off-axial conditions, we summarize and present an imaging theory of “quasi-coaxial” laser beams. The collimating optical system is designed by this imaging theory, and corresponding optical paths are modeling by the optical-design software. A prototype of multi-wavelength laser source is prepared under the guidance of optical paths model, and the parallelisms of “quasi-coaxial” beams are tested by a verification experiment. The experimental results show that the “quasi-coaxial” beams of 860 nm, 905 nm and 1064 nm (pulse/single) have well parallelisms.