Patent ID: 11867902
Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC G  B  F | IPC B  F  G

Claim 12:
13. A light guide panel that guides light emitted from a light source to a display panel, the light guide panel comprising:
an incident surface facing the light source;
an emission surface facing the display panel;
a first reflective surface facing the incident surface; and
a second reflective surface facing the emission surface, wherein
the first reflective surface has a concave shape that reflects light so that reflected light becomes closer to parallel light when viewed in a facing direction of the display panel and the light guide panel in the light guide panel, is tilted at an angle larger than 0 degrees with respect to the incident surface, and intersects the second reflective surface at an angle smaller than 90 degrees,
an incident angle θ1 of a light first incident on the second reflective surface after being reflected by the first reflective surface is larger than a critical angle θ2 which is a minimum angle at which total reflection occurs in the light guide panel, and
the light is reflected multiple times based on a difference between the incident angle θ1 and the critical angle θ2 and an inclination angle α of the second reflective surface with respect to an orthogonal direction to the incident surface until the light is emitted from the light guide panel.