Colors and Materials
Conventional LEDs are made from a variety of inorganic semiconductor materials. The following table shows the available colors with wavelength range, voltage drop and material:
| Color | Wavelength | Voltage drop | Semiconductor material | |
|---|---|---|---|---|
| Infrared | λ > 760 | ΔV < 1.63 | Gallium arsenide (GaAs) Aluminium gallium arsenide (AlGaAs) |
|
| Red | 610 < λ < 760 | 1.63 < ΔV < 2.03 | Aluminium gallium arsenide (AlGaAs) Gallium arsenide phosphide (GaAsP) Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP) |
|
| Orange | 590 < λ < 610 | 2.03 < ΔV < 2.10 | Gallium arsenide phosphide (GaAsP) Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP) |
|
| Yellow | 570 < λ < 590 | 2.10 < ΔV < 2.18 | Gallium arsenide phosphide (GaAsP) Aluminium gallium indium phosphide (AlGaInP) Gallium(III) phosphide (GaP) |
|
| Green | 500 < λ < 570 | 1.9 < ΔV < 4.0 | Indium gallium nitride (InGaN) / Gallium(III) nitride (GaN) Gallium(III) phosphide (GaP) Aluminium gallium indium phosphide (AlGaInP) Aluminium gallium phosphide (AlGaP) |
|
| Blue | 450 < λ < 500 | 2.48 < ΔV < 3.7 | Zinc selenide (ZnSe) Indium gallium nitride (InGaN) Silicon carbide (SiC) as substrate Silicon (Si) as substrate — under development |
|
| Violet | 400 < λ < 450 | 2.76 < ΔV < 4.0 | Indium gallium nitride (InGaN) | |
| Purple | multiple types | 2.48 < ΔV < 3.7 | Dual blue/red LEDs, blue with red phosphor, or white with purple plastic |
|
| Ultraviolet | λ < 400 | 3.1 < ΔV < 4.4 | Diamond (235 nm) Boron nitride (215 nm) Aluminium nitride (AlN) (210 nm) Aluminium gallium nitride (AlGaN) Aluminium gallium indium nitride (AlGaInN) — down to 210 nm |
|
| Pink | multiple types | ΔV ~ 3.3 | Blue with one or two phosphor layers: yellow with red, orange or pink phosphor added afterwards, or white with pink pigment or dye. |
|
| White | Broad spectrum | ΔV = 3.5 | Blue/UV diode with yellow phosphor |
Read more about this topic: Light-emitting Diode
Famous quotes containing the words colors and/or materials:
“Nature always wears the colors of the spirit. To a man laboring under calamity, the heat of his own fire hath sadness in it.”
—Ralph Waldo Emerson (1803–1882)
“Young children learn in a different manner from that of older children and adults, yet we can teach them many things if we adapt our materials and mode of instruction to their level of ability. But we miseducate young children when we assume that their learning abilities are comparable to those of older children and that they can be taught with materials and with the same instructional procedures appropriate to school-age children.”
—David Elkind (20th century)