Patent ID: 7001060

Claim:
An electronic device, comprising: a front light comprising: a light source; a light guide plate; and a plurality of prism-shaped lenses each being in direct contact with a lower surface of the light guide plate, wherein a cross-section of each of the prism-shaped lenses, in a plane perpendicular to the side surfaces thereof, has a shape of equally-sided trapezoid; and a reflective liquid crystal panel under the prism-shaped lenses; wherein a plane defined by an upper base of the equally-sided trapezoidal cross-section of each of the prism-shaped lenses comes into contact with the lower surface of the light guide plate; and an obtuse angle Φ of the equally-sided trapezoidal cross-section and a critical angle θ for the total reflection of the prism-shaped lenses satisfy the relationship of 90°<Φ≦90°+θ.