A light guide plate (20) includes a light incident surface (21) having a meso-nano pore structure (210) formed thereat, a bottom surface (22) adjacent to the incident surface. The meso-nano pore structure includes a plurality of meso-nano pores (211) which are less than 50 nm in size, a plurality of first meso-nano particles (212) disposed in the meso-nano pores, and a plurality of second meso-nano particles (213) disposed generally between the meso-nano pores. The meso-nano pores are considerably less than a wavelength (400.about.700 nm) of visible light in size, so that a nano-coupling effect occurs between photons of the lightbeams. Therefore, light loss caused by scattering is reduced, and a rate of utilization of light is improved.