Light-guide plate, area light source device, display device, manufacturing method for light guide plate

A manufacturing method for a light guide plate of manufacturing a light guide plate by an extrusion method, the light guide plate including:

• a light entrance surface through which light enters;
• a light exit surface that intersects with the light entrance surface and from which the light is emitted;
• and a facing surface that faces the light entrance surface, wherein the light having entered through the light entrance surface is guided to the facing surface side, and is emitted from the light exit surface, wherein a refractive index Nx in a direction perpendicular to the light entrance surface is higher than a refractive index Ny in a direction parallel to the light exit surface and parallel to the light entrance surface, the method comprising:
• a resin extrusion step of extruding a resin forming the light guide plate into a forming plate having a projection and recess shaped portion corresponding to a shape of the light guide plate;
• and
• a light guide plate forming step of pressing the forming plate while conveying the resin extruded in the resin extrusion step and forming the light guide plate,
• wherein the forming plate is disposed so that a surface of the projection and recess shaped portion, the surface corresponding to the light entrance surface, is orthogonal to a conveying direction of the resin.