Back in the day, lighting gels were necessary to change the color of a light source, but those days are long gone. Today, our homes and cities are shining bright, thanks to LEDs.
But how does a small diode allow LEDs to change color and supply an endless array of colors compared to traditional bulbs?
How Do LED Lights Change Color?
LEDs capable of changing color are made up of three separate diodes within the same bulb casing. These diodes are capable of emitting red, green, or blue colors. At full capacity, all three diodes will produce white light. To change the color of light produced by an LED, we simply adjust the intensity of each diode, which results in a wide range of colors.
Since LEDs are inevitable in our lives, it is interesting to learn about the Light Emitting Diode color Basics. This article is composed of a brief understanding guide to how colored LEDs work, whether you can change the color of your existing LEDs, and how color differs from color temperature.
Difference Between Color and Color Temperature
Before we progress, I must point out a significant difference between color and color temperature. ‘Color’ refers to the color of light that the diode emits – which can be any rainbow color. Color temperature refers to the shade of white color emitted.
White light is warm or cool depending on the temperature, and this is measured in degrees Kelvin.
The Kelvin scale was invented by a British physician, Lord Kelvin, who researched color changes in heated metals.
He discovered that when the temperature of a black material rises, its color changes from red to yellow and then to blue. Color temperature is an important consideration when designing any lighting system or setup.
When discussing color temperature, you should be familiar with Warm Colors and Cool Colors. Warm colors are those at the lower end of the color temperature spectrum, anywhere between 2,700K and 3,000K, while the Cool Colors have the highest color temperature, ranging from 5,000K to 10,000K.
Cool colored bulbs are often white or bluish-white, and daylight falls within this color temperature range. LEDs can produce up to 16 million different colors.
So, how do colored LEDs work?
Colored LEDs use three diodes to produce color: red, green, and blue (RGB). Because our eyes perceive all colors as varying mixes of red, green, and blue wavelengths, the RBG idea is an additive model. But first, let’s discuss this concept in great depth.
A Deep Dive into The RGB Concept
Let’s go on a colorful journey down memory lane.
You may recall from school that blending blue and yellow pencils on paper produced the color green. And the primary colors are red, blue, and yellow, which are combined to form secondary colors.
Surprisingly, this model of color mixing is just ONE of two that exist in the visible world. The subtractive CMYK paradigm, in which the lack of color equals white, is the second way to mix colors.
The source of color is that the equivalent wavelength of sunlight is reflected in our eyes rather than absorbed by an object.
This color model is commonly used in photography and magazine printing, where several colored inks are blended to create additional hues.
In the additive model of color mixing, in which the absence of color equals black, light photons emitted by various metal alloys are the source of color.
The aluminum indium gallium phosphide (AlInGaP) material system is used in red and amber LEDs. Green diodes employ gallium phosphide, whereas blue diodes use indium gallium nitride.
This is how the RGB colors, red, green, and blue, came about.
This is what we’re concerned about in this blog because this color mixing approach is used in TVs, monitors, and gadgets.
They use variable intensities to illuminate RED, GREEN, or BLUE lights in a black pixel to produce over 16 million colors.
White light is produced when current flows through all three diodes at the same intensity.
Because LEDs are so tiny and the diodes are so close together, our eyes sense the color combination rather than each colored diode.
An extra three colors may be made by changing the current such that it only passes through two diodes. A current sent through the red and blue diodes make magenta, a current through the red and green diodes produces yellow, and a current through the blue and green diodes produces cyan.
Here’s a table that shows the primary color outputs you’ll receive when you blend different colors.
Alternating The Current To Each RGB Stream
Other colors may be produced by varying the amount of current flowing through each diode.
If the red and green diodes are both turned on, but the green is only 50% charged, a hue somewhere between red and yellow is produced. In this instance, orange.
Now, let’s look at some amazing math to see how many colors one RGB LED can produce.
The RGB model employs a color code to quantify the intensity of each diode.
If you’ve worked in graphic design or web development, you’re undoubtedly acquainted with this.
Each diode is assigned a numeric value between 0 and 255 using the RGB color coding.
To continue with the previous example, the color code for orange would be 255, 128, 0. This can also be presented in percentage form, 100%, 50%, and 0%.
With the slide of a remote, you can access 256*256*256 = 16,777,216 different colors since each of the three colors may be adjusted to 256 values (including zero).
Yes, all of this by combining only three primary colors. You may experiment with this color picker to see how it works.
Simply change the RGB color values and watch what happens.
A microcontroller is employed in color-changing LEDs to regulate whether each diode is turned on or off.
To dim a diode, PWM is used, whereas LEDs employ PWM (PWM).
PWM, as the name implies, operates by rapidly switching the diode on and off. This flashing is so quick that the human eye cannot notice it.
As a result, our eyes can only see the net result i.e., the color.
The majority of LEDs flicker at 1000Hz, but the human eye can only detect flickers that are slower than 200Hz.
Difference Between RGB and RGBW LED Lights?
A conventional RGB LED has three colored diodes; an RGBW LED, on the other hand, has four diodes, one of which is white.
This white diode emits pure white light, so when you require white, just the white diode is active.
When you need colors, the other three come into play.
In addition to all of the colors produced by an RGB light, an RGBW LED can produce bright pastel hues.
Furthermore, and more crucially, because of the high CRI white LED, RGBW’s light output is ideal for task or mood lighting, and you can see objects.
But wait, there’s more!
The RGBW LED can also modify the color temperature of the generated light!
If you need task illumination, the white and blue diodes combine to provide a cool temperature.
If you wish to unwind, the red and white diodes emit a familiar warm white light.
If you don’t need brightness or task lighting, a basic RGB LED can do to give color and beauty.
The third distinguishing feature is the quality of the white light generated.
The white hue generated by the RGBW LED is a purer tone of white, but in RGB, the three colors combine to give a somewhat bluish-white, which can be off-putting.
Here’s a cool video demonstrating the difference in the brightness and color range between an RGB and an RGBW LED.
How Does LED Change The Color Temperature?
Overall, changing the color of an LED is straightforward, but can the same be true for altering the color temperature of a bulb?
Unfortunately, it is not that simple.
LEDs are made to generate precise Kelvin colors, which implies that the color temperature is set and cannot be modified once they are built.
Warm lights help us relax, while blue lights assist us to stay awake.
As a result, this is infuriating, because some sections of the house are used for both resting and focusing.
It is impossible to have the best of both worlds.
Fortunately, manufacturers have recognized this dilemma and developed LED fixtures with variable color temperatures.
These fixtures include two sets of LED chips, cool and warm temperatures, that users may switch between.
To learn more about how temperature-changing LEDs function, watch this video by SIRS-Electronics:
Can You Change The Color of an LED Bulb?
Despite the fact that the technology is simple, color-changing LEDs are difficult to adjust. Let’s dissect it.
To begin, there are two kinds of color LEDs: single-colored and multi-colored. If an LED is always going to be a constant red hue, for example, including the green and blue diodes inside the case would be unnecessary. Because they would always be turned off.
Because single-color LEDs lack the necessary components, it is physically impossible for them to change color.
Alternatively, the majority of colored LEDs will include all three basic colored diodes. They may be able to cycle through a range of colors, but the combinations will be defined by the producer of the LEDs.
A tiny onboard computer controls the hue of light that can be emitted. It’s doubtful that you’ll be able to change the color of your LEDs unless you have access to this computer.
Nonetheless, smart LEDs have grown in prominence in the last year. This cutting-edge technology lets you change the color of LED lights using a remote control or a smartphone app.
Can You Convert Standard White LED Into RGB?
So you have an idea for a pleasant area and believe you have some LED strips in storage. Unfortunately, they’re just plain white!
Can you convert them to RGB and obtain color?
Unfortunately, no. As I previously stated, except for a few improvised sanding and coloring at-home hacks, you cannot convert your standard single white color LED into the three colored RGB LED.
But don’t be discouraged since it’s a perfect opportunity to do some DIY bulb painting with your kids.
What Does Daylight, Cool & Warm Mean in Light Bulbs?
When it comes to light bulbs, the phrases warm white, daylight, and cool white all have different meanings.
The Kelvin temperature scale defines color differences, and light as seen by the human eye has a distinct appearance for each type of bulb.
Kelvin Color Temperatures
The color temperature of light bulbs ranges along the Kelvin absolute temperature scale. The colder the light seems, the higher the Kelvin value. The following definitions apply under this system:
- Warm white light bulbs have a color temperature ranging from 2500K up to 3000K. Warm whites have a yellow tone, which is considered a “warm” color.
- Warm white light bulbs are colors with a temperature ranging from 2500K up to 3000K. Warm whites have a yellow tone and are classified as a “warm” hue.
- Cool white bulbs fall between 3100K and 4500K. At the high end of this spectrum, the light appears as a bright, neutral white that blends into blue shades.
- Daylight bulbs feature color temperatures ranging from 4600K to 6500K or greater. These bulbs emit light that is tinted with blue and closely resembles the natural hue of daylight, which is 5600K on a bright day at midday.
Light Bulb Colors, Mood and Room Use
The color temperature of a light bulb may influence mood as well as how colors appear in the room.
Most people are familiar with warm white since it is the color of light generated by most incandescent lamps.
Warm white lighting conveys a sense of coziness, peace, and relaxation, making it suitable for bedrooms, dining areas, and living spaces.
This bright tint improves warm paint colors but might make cool colors appear boring.
Some purples, for example, might seem brown under warm lighting.
Cool white light has a vibrant flair and complements cool colors like whites, blues, and greens.
Because of its sharpness, this sort of light is ideal for bathrooms and workspaces such as kitchens, home offices, basements, and garages.
Lighting using daylight bulbs generates colorful and powerful lighting that is frequently viewed as being too harsh for usage in the house.
However, because it provides good light for detail-oriented work, it is suitable for a home workshop, sewing, or craft area.
Daylight bulbs can also be used to illuminate a showcase space, such as shelves containing books or memorabilia, as well as for security lighting.
Color Rendering
When color perception is critical, the capacity of light bulbs to render color must be taken into account.
This property, which is distinct from color temperature, is determined by the color rendering index, or CRI, of the bulb.
The CRI is a number ranging from 0 to 100, with higher numbers representing the best color rendering light bulbs.
The CRI of most incandescent and halogen lamps is close to 100. Even though they have the same color temperature, fluorescent bulbs can have CRIs ranging from 75 to 90.
Look for a light bulb with a color temperature close to 5000K and a CRI of 90 or higher if you are performing work that demands accurate color rendering as well as powerful illumination for detail.
Conclusion
That’s all about color-changing LEDs. You will agree with me that the technology involved is quite simple to understand.
This color appearance is unique to LEDs and cannot be replicated with standard halogen or incandescent light bulbs.
As a result, it’s no wonder that LEDs are growing more popular and are progressively being integrated into a wide spectrum of applications.
What are your thoughts on colorful LEDs?
Please let me know in the comments!