Liquid crystal display devices are widely used because they have the advantages such as thin profile, low power consumption, no radiation, etc. At present, most of liquid crystal display devices include a display panel and a backlight module disposed on the back side of the display panel, the backlight module is used for providing a uniform light source for the display panel, so that the display panel is capable of displaying images normally. The backlight module usually includes a light source, a light guide plate, a reflection piece, a rubber frame, and so on.