Direct backlight module

A direct backlight module, comprising:

• a frame;
• at least a light source, being arranged in the frame;
• and
• a diffuser having a top surface and a bottom surface, the diffuser being disposed over both the frame and the at least a light source, the diffuser being doped with micro particles for light scattering;
• wherein a diffusion unit and a collimation unit are formed on the top surface of the diffuser while using the diffusion unit for scattering light incident to the bottom surface and the collimation unit for collimating light incident to the bottom surface,
• wherein the diffusion unit further comprises at least a semi-lenticular lens, and the collimation unit further comprises at least a prism,
• wherein each semi-lenticular lens is characterized by a specific radius of curvature preferably in the range of 10 microns to 500 microns, and each prism is characterized by a vertex angle preferably in the range of 30° to 104° and a specific height, and
• wherein the specific height of each prism is varying along the axis of the same, and the specific radius of curvature of each semi-lenticular lens is varying along the axis of the same.