A light-emitting device and an electronic apparatus including the light-emitting device are provided. The light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer between the first electrode and the second electrode. The interlayer includes an emission layer, a hole transport region between the first electrode and the emission layer, and an electron transport region between the emission layer and the second electrode. The emission layer includes a first quantum dot, the hole transport region includes a second quantum dot, and the electron transport region includes a third quantum dot. The first quantum dot to the third quantum dot may be understood by referring to the description of the first quantum dot to the third quantum dot provided herein.

This technology is directed to the preparation of doped-bismuth-silicate seed crystals through controlled crystallization (e.g. dimensionality of growth and nucleation mechanism) and the method of forming high purity single seed (particle size ranges from micrometers to millimeters) for various uses. These seed crystals have a nominal stoichiometry of Bi.sub.2-xA.sub.xSiO.sub.5, Bi.sub.2-xA.sub.xSi.sub.3O.sub.9, Bi.sub.4-xA.sub.xSi.sub.3O.sub.9, and Bi.sub.12-xA.sub.xSiO.sub.20, where A is a rare earth dopant selected from La, Ce, Nd, Pr, and/or Sm.

Quantum dot layers and display devices including quantum dot layers are described. In an embodiment the quantum dot layer includes quantum dots with coatings to adjust the spacing between adjacent quantum dots. In an embodiment, the coatings are metal oxide coatings and may create a charge transporting matrix. In an embodiment, the coatings are core-material coatings. The QD layers may be QD-LED compatible.

A device including an LED light source optically coupled to a phosphor material including a green-emitting phosphor selected from the group consisting of compositions of (A1)-(A70), and combinations thereof.

This technology is directed to the preparation of doped-bismuth-silicate seed crystals through controlled crystallization (e.g. dimensionality of growth and nucleation mechanism) and the method of forming high purity single seed (particle size ranges from micrometers to millimeters) for various uses. These seed crystals have a nominal stoichiometry of Bi.sub.2-xA.sub.xSiO.sub.5, Bi.sub.2-xA.sub.xSi.sub.3O.sub.9, Bi.sub.4-xA.sub.xSi.sub.3O.sub.9, and Bi.sub.12-xA.sub.xSiO.sub.20, where A is a rare earth dopant selected from La, Ce, Nd, Pr, and/or Sm.

Quantum dot layers and display devices including quantum dot layers are described. In an embodiment the quantum dot layer includes quantum dots with coatings to adjust the spacing between adjacent quantum dots. In an embodiment, the coatings are metal oxide coatings and may create a charge transporting matrix. In an embodiment, the coatings are core-material coatings. The QD layers may be QD-LED compatible.

Provided is a photochromic substance that has lower toxicity, exhibits good sensitivity in a visible light region, changes color deeply, has slow speed of color fading, has chemical and thermal stability, and has good durability. The photochromic substance has a composition represented by the formula:
Ba.sub.(a-b)Ca.sub.bMg.sub.cSi.sub.dO.sub.e:Fe.sub.fM.sub.gM.sub.h where 1.8a2.2, 0b0.1, 1.4c3.5, 1.8d2.2, e=(a+c+2d), 0.0001f, 0.0001g, 0h, M is at least one of Al and Eu, and M is at least one element selected from the group consisting of Na, K, Nd, Li, S, C, Ti, V, Mn, Cr, Cu, Ni, Co, Ge, Zn, Ga, Zr, Y, Nb, In, Ag, Mo, Sn, Sb, Bi, Ta, W, La, Ce, Pr, Nd, Sm, Gd, Er, Ho, Tb, Tm, Yb, Lu, P, Cd, and Pb.