Substrate with wavy surface to control specular visibility for electronic device and electronic device using same
View Patent ↗Provided is an electronic device having a long life and a large effective area. Furthermore, provided is an optical device capable of controlling specular visibility. And provided is a substrate for the optical device, which includes a scattering layer having excellent scattering properties and having a desired refractive index while retaining surface smoothness. Further, there is provided a substrate for the electronic device, which includes a substrate having first and second main surfaces facing each other and an electrode pattern formed on the first main surface of the substrate, in which the first main surface of the first and second main surfaces is a surface which forms waviness made up of curved faces, the waviness of the surface has a wavelength Rλa of greater than 50 μm and a ratio Ra/Rλa of waviness roughness Ra of the surface which forms waviness to the wavelength Rλa of the waviness is from 1.0×10 −4 to 3.0×10 −2 .
1. A substrate for an electronic device, comprising:
a translucent glass substrate having a first main surface and a second main surface, the first and second main surfaces facing each other, the translucent glass substrate comprising a glass layer formed on the first main surface of the translucent glass substrate; and
an electrode pattern formed on the first main surface of the translucent glass substrate,
wherein the first main surface is a surface which forms waviness made up of curved faces,
the waviness of the surface has a wavelength Rλa of greater than 50 μm,
a ratio Ra/Rλa of waviness roughness Ra of the surface which forms a waviness to the wavelength Rλa of the waviness is from 1.0×10 −4 to 3.0×10 −2 ,
the glass layer having a second surface abutting on a side of the first main surface of the translucent glass substrate and a first surface, opposite to the second surface, which forms waviness made up of curved faces,
the translucent glass substrate further comprising a scattering layer formed on the first main surface of the translucent glass substrate and made from a glass comprising a base material which has a first refractive index for at least one of wavelengths of transmitted light and a plurality of scattering materials being dispersed in the base material and having a second refractive index different from the first refractive index of the base material, and
distribution of the scattering materials in the scattering layer diminishes from the inside of the scattering layer toward a translucent electrode formed as a first electrode on the first surface, wherein a density ρ 3 of the scattering materials at a distance x (x≦0.2 μm) from a surface of the scattering layer on a translucent electrode side and a density ρ 4 of the scattering materials at a distance x of 2 μm satisfy ρ 4 >ρ 3 .
2. The substrate for an electronic device according to claim 1 , wherein an organic LED element is formed on the first main surface.
3. The substrate for an electronic device according to claim 1 , wherein the second main surface is flatter than the first main surface.
4. The substrate for an electronic device according to claim 1 , wherein the surface which forms waviness has a surface roughness Ra of 30 nm or below.
5. An electronic device comprising a translucent glass substrate;
the translucent glass substrate having a first main surface and a second main surface, the first and second main surfaces facing each other, and the translucent glass substrate comprising a glass layer formed on the first main surface of the translucent glass substrate; and
an electrode pattern formed on the first main surface of the translucent glass substrate,
wherein the first main surface is a surface which forms waviness made up of curved faces,
the waviness of the surface has a wavelength Rλa of greater than 50 μm,
a ratio Ra/Rλa of waviness roughness Ra of the surface which forms a waviness to the wavelength Rλa of the waviness is from 1.0×10 −4 to 3.0×10 −2 ,
the glass layer having a second surface abutting on a side of the first main surface of the translucent glass substrate and a first surface, opposite to the second surface, which forms waviness made up of curved faces,
the electronic device further comprising a scattering layer formed on the first main surface of the translucent glass substrate and made from a glass comprising a base material which has a first refractive index for at least one of wavelengths of transmitted light and a plurality of scattering materials being dispersed in the base material and having a second refractive index different from the first refractive index of the base material, and
distribution of the scattering materials in the scattering layer diminishes from the inside of the scattering layer toward a translucent electrode formed as a first electrode on the first surface, wherein a density ρ 3 of the scattering materials at a distance x (x≦00.2 μm) from a surface of the scattering layer on a translucent electrode side and a density ρ 4 of the scattering materials at a distance x of 2 μm satisfy ρ 4 >ρ 3 .