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:
“In Haydn’s oratorios, the notes present to the imagination not only motions, as, of the snake, the stag, and the elephant, but colors also; as the green grass.”
—Ralph Waldo Emerson (1803–1882)
“If only it were God’s will that printed and written materials have as much influence on the people as the princes and their censors fear! Considering the countless good books we have, the world would have changed for the better a long time ago.”
—Franz Grillparzer (1791–1872)