Soft lamination is to laminate the soft film materials on the soft or hard materials, such as laminating the OCA glue film on the glass panel or LCD, laminating the polarizer film on the LCD screens, you have to take this solution if your material is soft, most of the soft lamination machine works with a roller for applying the soft film on the soft or hard materials.
Hard lamination is to laminate 2 pieces hard materials together, such as laminate a glass panel on the LCD/OLED screen,you have to make sure both materials that you want to laminate is hard, and this solution always work under vacuum. So we also call it vacuum lamination machine.