太阳以电磁波的形式向外辐射能量,其中有一部分的电磁波就是我们所能看到的可见光。可以想象的是,光是以波浪的形式抵达地球表面的,所以在自然界中,除非人为因素,光始终是以凸面波(发散光)的形式存在,因此可以利用凸透镜来得到会聚光。 The sun radiates energy in the form of electromagnetic waves, some of which are the visible light we can see. It is conceivable that light reaches the surface of the earth in the form of waves, so in nature, unless human factors, light always exists in the form of convex waves (divergent light), it is possible to use a convex lens to obtain convergent light.