Surface light source module and dual-sided transparent display device

A surface light source module, comprising:

• a light guide plate, having a first surface, a second surface, and a light incident surface, wherein the first surface is opposite to the second surface, the light incident surface is connected to the first surface and the second surface, and the first surface is provided with multiple microstructures;
• a light source component, disposed opposite to the light incident surface;
• a covering layer, disposed opposite to the first surface;
• and
• an optical adhesive layer, disposed between the light guide plate and the covering layer and covering the microstructures,
• wherein each of the microstructures has a first structural surface connected to the first surface, each of the microstructures has a symmetry plane, the symmetry plane is perpendicular to the first surface, an included angle between the symmetry plane and the light incident surface is from 45 degrees to 90 degrees, an intersection between the first structural surface and the symmetry plane has a first intersection line, the first intersection line comprises a first-part line segment, a second-part line segment, and a third-part line segment, the first-part line segment or the third-part line segment is connected to the first surface, the second-part line segment is connected between the first-part line segment and the third-part line segment, the optical adhesive layer at least contacts the second-part line segment of the first intersection line of the first structural surface, there is a first included angle between a tangent line at each position on the first-part line segment and the first surface, there is a second included angle between a tangent line at each position on the second-part line segment and the first surface, there is a third included angle between a tangent line at each position on the third-part line segment and the first surface, the first included angle has a maximum value of the first included angle, the third included angle has a minimum value of the third included angle, the maximum value of the first included angle is greater than 0 degrees and less than or equal to 40 degrees, the minimum value of the third included angle is greater than or equal to 50 degrees and less than or equal to 90 degrees, and a ratio of a first length of the first-part line segment to a total length of the first intersection line is greater than or equal to 5%, a ratio of a third length of the third-part line segment to the total length of the first intersection line is greater than or equal to 5%, and the second included angle is gradually increased from the maximum value of the first included angle to the minimum value of the third included angle.

A dual-sided transparent display device, comprising:

• a transparent display panel;
• and
• two surface light source modules, wherein the transparent display panel is disposed between the two surface light source modules, and each of the two surface light source modules comprises:
• a light guide plate, having a first surface, a second surface, and a light incident surface, wherein the first surface is opposite to the second surface, the light incident surface is connected to the first surface and the second surface, the second surface is adjacent to the transparent display panel, and the first surface is a light-emitting surface and is provided with multiple microstructures;
• a light source component, disposed opposite to the light incident surface;
• a covering layer, disposed opposite to the first surface;
• and
• an optical adhesive layer, disposed between the light guide plate and the covering layer and covering the microstructures,
• wherein each of the microstructures has a first structural surface connected to the first surface, each of the microstructures has a symmetry plane, the symmetry plane is perpendicular to the first surface, an included angle between the symmetry plane and the light incident surface is from 45 degrees to 90 degrees, an intersection between the first structural surface and the symmetry plane has a first intersection line, the first intersection line comprises a first-part line segment, a second-part line segment, and a third-part line segment, the first-part line segment or the third-part line segment is connected to the first surface, the second-part line segment is connected between the first-part line segment and the third-part line segment, the optical adhesive layer at least contacts the second-part line segment of the first intersection line of the first structural surface, there is a first included angle between a tangent line at each position on the first-part line segment and the first surface, there is a third included angle between a tangent line at each position on the third-part line segment and the first surface, the first included angle is greater than 0 degrees and less than or equal to 30 degrees, the third included angle is greater than or equal to 50 degrees and less than or equal to 90 degrees, and the second-part line segment is a curve;
• and
• a ratio of a first length of the first-part line segment to a total length of the first intersection line is greater than or equal to 5%, and a ratio of a third length of the third-part line segment to the total length of the first intersection line is greater than or equal to 5%.