采用矢量场模型，对具有诱人应用前景的圆柱形垂直腔面发射半导体激光器(VCSEL)的模式阈值增益进行了数值模拟；为减弱金属圆柱的反射以使理论计算更接近实际，采用两种方案，将外加金属包壳视为非理想导体，或在此基础上，将金属包壳与激光器主体结构隔开．从模式的阈值增益与顶Bragg反射镜层周期数的关系方面，与理想金属外包壳情况进行了比较．结果表明，高阶贝塞耳函数模式的阈值增益变化规律基本相同，而0阶贝塞耳函数模式的阈值增益变化规律相差较大．

The modal threshold gain of cylindrical and oxide-confined vertical-cavity surface-emitting laser (VCSEL) with potential applications in optical communication and optical interconnect,is simulated numerically by using Vectorial Field Model. To weaken the parasitic reflections from the shell(perfectly conducting metal cylinder),more practically,it is considered the shell as non-perfect conducting one,or moreover,it is supposed that the shell is separated from the laser. The threshold gain versus pair number of top Bragg mirror in the two situations is compared with that in the case of perfectly conducting metal cylinder. The result shows that the threshold gain curves are similar for high-order Bessel modes,and they are quite distinct for O-order Bessel modes.