Disclosed are a backlight module and a display device and method using the same, the backlight module comprises light-guide plate (302), an optical film (303) attaching to a side of a light emitting face of the light-guide plate (302), and a strip-like assembly (301) of point light source disposed at the side of the light incident face of the light-guide plate (302), the strip-like assembly (301) of point light source comprises point light sources toward the light incident face of the light-guide plate (302) thereon, an edge of one side of the optical film (303) corresponding to the light incident face of the light-guide plate (302) is provided with indents (303a).