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 0:
1. A display device comprising:
a light source that emits light;
a display panel that displays an image; and
a light guide panel that guides light emitted from the light source to the display panel, wherein
the light guide panel includes 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,
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, and
the light guide panel reflects a light first incident on the second reflective surface at an incident angle θ1 after being reflected by the first reflective surface such that the incident angle θ1 is larger than a critical angle θ2 which is a minimum angle at which total reflection occurs in the light guide panel and such that 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.