beam spread

基本解释

Incandescent reflector test lamps shall be of the widest beam spread available. A Type MR test lamp shall have a dichroic reflector.
带反光杯的白炽灯测试用灯泡应当有最宽的扩展光束，MR型测试灯应当有分色反射灯。
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The coupling among laser modes and the relations between equivalent beam spread angle and the surface deformation of the mirrors are obtained.
给出了激光模式之间的耦合以及等效光束发散角与镜面变形量之间的关系。
Light sent into the oil layer was confined there, bouncing between the metal and air boundaries. The beam spread out ever more quickly, generating a trumpet-shaped glow (see image).
当把光传入油层后，就被约束在那里，光线在金属和空气的边界之间不断反弹，于是产生了喇叭状的辉光（见图片）。