Abstract: The present invention provides a high-precision planar light source with a sufficiently uniform luminance and sufficient light directivity to direct light to travel in a specific direction, using a simple production process. More specifically, the invention provides: a glass substrate with light directivity produced by applying a paste containing at least one member selected from the group consisting of lithium compounds, sodium compounds, potassium compounds, rubidium compounds, cesium compounds, copper compounds, silver compounds, and thallium compounds, an organic resin, and an organic solvent to one or both sides of a glass substrate containing an alkali metal as a glass component, and then performing heat treatment at a temperature lower than the softening temperature of the glass substrate; and a planar light source using the glass substrate.

Abstract: A surface coating applied to a subject surface includes an undercoating, a color base layer, coated over the undercoating layer, which contains a coloring material, and a color clear layer, coated over the color base layer, which contains a coloring dye of a hue within +/-10 from a hue of the coloring material of the base color layer on the 100-division Mansell hue ring.

Abstract: A surface coating applied to a subject surface includes an undercoating, a color base layer, coated over the undercoating layer, which contains a coloring material, and a color clear layer, coated over the color base layer, which contains a coloring dye of a hue within +/-10 from a hue of the coloring material of the base color layer on the 100-division Mansell hue ring.The color clear layer may be applied with a paint spray device while rotating the subject surface around an axis and continuously moving the subject surface along the axis to form a spiral pattern of paint spray relative to and around the subject surface at regular pitches. Preferably, the ratio of each of the regular pitches to a width of the pattern of paint spray is less than 0.3.