Consider first a light wave spreading out from a point source.

点光源一个好的例子是你家里的电灯泡。

youdao

Supply LED light source, digital point light source, LED lights, box lights.

供应LED点光源，数码点光源，LED灯，方块灯。

youdao

Supply LED light source, digital point light source, LED lights, box lights.

供应LED点光源，数码点光源，LED灯，方块灯。

youdao