How Do LED Lights Change Color?
- 3 Mar 2025
Thanks to the considerably improving energy efficiency and environment friendliness compared to traditional incandescent lights, LED lights enjoy a surging adoption. It doesn’t stop here. The decades of development have made LED technologies more “charming.”
Not just in the lighting performance but its adaptability to make the regional lighting system more anesthetic pleasant and color changing is one of the ground-breaking ones. Be it for interior designs or building decoration, color-changeable LED lights are the tendency. In this blog, we will explore how LED lights change colors.
How LEDs Produce Light
LEDs, or Light Emitting Diodes, are semiconductor devices that emit light when an electric current passes through them.
This process, known as electroluminescence, involves electrons moving through the semiconductor material, releasing energy in the form of photons. The specific materials used in the semiconductor determine the color of the emitted light.
For instance, red diodes often use aluminum gallium arsenide, green diodes utilize gallium phosphide, and blue diodes are made with indium gallium nitride.
Dimming and Color Control
Various techniques are employed to adjust the brightness and color of LED lights:
Triac (Phase-Cut) Dimming
This method modifies the voltage waveform to reduce power to the LED, effectively dimming the light. It’s simple and cost-effective, making it popular in residential settings.
0-10V Dimming
An analog control method where a voltage signal between 0V (off) and 10V (full brightness) adjusts the light’s intensity. It’s commonly used in commercial lighting systems.
DALI (Digital Addressable Lighting Interface)
A digital protocol that allows for precise control of individual fixtures in complex lighting systems. It enables features like scene setting and is suitable for large-scale installations.
DMX512
Originally developed for stage lighting, DMX512 is an advanced digital control protocol that manages multiple lighting devices. It’s widely used in theatrical, architectural, and entertainment lighting due to its flexibility and precision.
PWM vs DC: What’s the Difference Between PWM & DC
To achieve dimming effects, two primary methods are utilized
DC Dimming
DC Dimming is a technique used to adjust the brightness of LED lights by varying the direct current (DC) supplied to the LEDs.
By reducing the current, the light output decreases, resulting in lower brightness levels. Conversely, increasing the current enhances the brightness. This method is straightforward and can improve energy efficiency, as lowering the power to the LEDs at reduced brightness levels can lead to better battery life in devices.
However, it’s important to note that DC Dimming can have some drawbacks. For instance, at lower brightness levels, it may lead to color accuracy issues or “black crush,” where dark areas lose detail.
Additionally, while DC Dimming can reduce flickering associated with other dimming methods, it might introduce other visual artifacts.
PWM Dimming (Pulse Width Modulation)
Pulse Width Modulation (PWM) dimming is a technique used to control the brightness of LED lights by rapidly switching them on and off at a high frequency.
This method adjusts the perceived brightness by varying the proportion of time the LED is in the ‘on’ state versus the ‘off’ state within each cycle, a concept known as the duty cycle. For instance, a 25% duty cycle means the LED is on for 25% of the time and off for 75%, resulting in lower brightness, while a 75% duty cycle increases the brightness accordingly.
One of the key advantages of PWM dimming is its ability to maintain the LED’s color characteristics across different brightness levels. Since the LED is either fully on or completely off during each cycle, the spectral output remains consistent, ensuring accurate color representation. Additionally, PWM dimming is highly efficient, as it minimizes energy loss by avoiding partial conduction states that can occur in other dimming methods.
However, it’s important to implement PWM dimming with an appropriate frequency, typically above 200 Hz, to prevent any visible flicker that could be perceptible to the human eye. Properly designed PWM dimming systems can achieve smooth and flicker-free dimming performance, making them suitable for various applications, including those requiring precise color control and dynamic lighting effects.
LEDIA Lighting Advanced LED Lighting Solutions for Your Projects
Understanding these principles and control methods is crucial for selecting and implementing LED lighting systems that meet specific aesthetic and functional requirements.
For comprehensive support in your linear lighting projects, consider partnering with LEDIA Lighting, a leader in innovative LED solutions.