这个效果也叫放大镜效果，最早好像在ppg出现的，之后就有了很多仿制品出来了。

一般用于放大查看商品图片，在凡客，京东商城，*等都有类似的效果。-This effect is also called a magnifying glass effect, first appears as if ppg, after there is a lot of imitations out.

Usually for amplifying view product images, all passengers, Jingdong Mall, Alibaba have similar effects.