Its function, characteristic, usage and limited condition are presented. Take the SLD with absorption region for example, the device is simulated and the good simulating results are obtained.

• 本文介绍了它的功能、特点、使用方法以及适用条件，并且以SLD直条形波导吸收区为例进行了模拟，得到了很好的模拟结果。