The wavelength of a yellow LED typically falls within the range of 577-597 nanometers (nm). This specific range corresponds to what our eyes perceive as the color yellow within the visible spectrum of light.
Understanding Yellow LED Wavelength
Light Emitting Diodes (LEDs) produce light at specific wavelengths depending on the semiconductor materials used in their construction. For yellow LEDs, these materials are engineered to emit photons with energy levels that correspond to wavelengths in the yellow portion of the visible light spectrum.
As confirmed by the reference, the wavelength associated with yellow light is generally accepted to be in the 577 nm to 597 nm range.
Why Wavelength Matters for Color
The color of visible light is determined by its wavelength. Different wavelengths are perceived by the human eye as different colors:
- Violet: ~380–450 nm
- Blue: ~450–495 nm
- Green: ~495–570 nm
- Yellow: ~570–590 nm (Reference range: 577-597 nm)
- Orange: ~590–620 nm
- Red: ~620–750 nm
(Note: Ranges can vary slightly depending on the source, but the reference provides the specific range for yellow light relevant to this answer).
The human eye is compatible with a small region of the electromagnetic spectrum, known as visible light, which is why we can see colors like yellow when a source, such as an LED, emits light in the 577-597 nanometer range.
Practical Applications
Yellow LEDs are used in numerous applications, including:
- Indicator Lights: Often used in electronics for signaling states.
- Traffic Signals: Historically, some traffic lights used yellow LEDs (or filtered incandescent bulbs) for the "caution" signal. Modern signals predominantly use LEDs for energy efficiency.
- Automotive Lighting: Used in turn signals, side markers, and sometimes fog lights.
- Signage: Used in display signs for visibility.
- Decorative Lighting: Providing warm, distinct illumination.
Each of these applications relies on the LED producing light within the specific wavelength range that the human eye interprets as yellow.
Summary of Yellow Light Wavelength
| Color | Approximate Wavelength Range (nm) |
|---|---|
| Yellow | 577-597 (According to Reference) |
Understanding the specific wavelength helps in selecting the correct LED for a desired visual effect or application.
