The difference between Han Yu's transformation card and Xiao Ka.

The conversion card is a prism that simply refracts light by using the optical principle. A small card is a card attached to an album.

The technical term of deformation card is called three-dimensional deformation card, or three-dimensional deformation card, with a slightly different name. The imaging principle is that a picture is densely covered with rows of small prisms. The small card is attached to Aidou's selfie card or official photo card (given by the company).