注意：
be careful:
1.更换时请注意现场环境，建议拆掉在办公室等相对环境较好的地方更换
Please pay attention to the on-site environment during replacement. It is recommended to remove it and replace it in a relatively good environment such as the office
2.安装时轻拿轻放，注意安装时的水平放置
Handle with care during installation, and pay attention to the horizontal placement during installation
3.务必清理枪体外部
Be sure to clean the exterior of the gun body
聚焦镜片的更换
准直镜片的更换
反射镜片的更换
保护镜片的更换