What Are the Different Types of Light Bulbs?
The electric light bulb has been considered one of the most valuable inventions since the human-made fire. This incredible innovation greatly influenced the Industrial Revolution: extended working hours, safer evening travel, orderly social life after dark, etc.
There's an interesting fact: although we're all taught in history that Thomas Edison invented the light bulb in 1879, the invention was a complicated process involving many inventors across the globe for around 150 years. The first artificial light sources can be traced back to the 1700s, much earlier than Edison's birth.
Light bulbs would change the world; however, it took a while to become commonplace for every family worldwide. For example, only 50% percent of the families in the United States had electricity a century ago; from then until the 1980s, choosing which bulb to buy for your lighting fixture was simple because there was only one choice — the conventional incandescent bulb.
From indoor lamps and overhead lighting to patio lanterns and reading lights for the bed, there's an appropriate bulb for every fixture. However, choosing a suitable bulb for lighting fixtures has been complicated because of the emergence of a wide array of light bulbs.
Our blog will provide the basic information on 5 different types of light bulbs, and you will know the difference between watts and lumens, then lighting colors for each type of light bulb.
5 Types of Light Bulbs
- Incandescent Bulb
- Halogen Bulb (improved incandescent bulbs)
- Standard Fluorescent Bulb
- CFL (compact fluorescent lamps)
- LED (light emitting diode)
What is it: The incandescent light bulb is a source of electric light that works by incandescence, which emits light by heating the filament. It is the original form of electric lighting and has been in use for over 100 years.
How it works:Basically, an incandescent light bulb is a controlled fire on display in a contained and controlled environment, which is usually within the glass. When an electrical current touches the bulb's base, electricity will enter and heat the tungsten filament housed inside. Then, the filament will heat up, and the "incandescence" will finally be created; that's how an incandescent bulb produces light by heat. Similarly, the same chemical effect happens when a log or coal is burning.
Halogen Bulb (improved incandescent bulbs)
What is it: The halogen bulb can also be called a quartz halogen and tungsten halogen bulb. Most importantly, it's an advanced form of the incandescent bulb. Halogen light bulbs apply a fused quartz envelope, so they usually have higher temperatures than a standard incandescent bulb. The quartz envelope used to have a vapor inside (originally iodine), but now it's usually bromine.
How it works: Halogen bulb is a type of light bulb that has a tungsten filament similar to the standard incandescent bulb; however, halogen ones are much smaller for the same wattage and have halogen gas. Halogen gas enables the filament to evaporate at a higher temperature, resulting in a mix of tungsten and vapor instead of being deposited on the envelope. As a result, the regenerated cycle makes halogen bulbs have better performance on energy efficiency.
Standard Fluorescent Bulb
What is it: Fluorescent bulbs are cooler and much more energy-efficient than incandescent bulbs. Fluorescent bulbs produce light through fluorescing a phosphor coating; a fluorescent bulb consists of a glass tube filled with a mixture of mercury and argon vapour.
How it works: The sealed glass tube is the critical element in a fluorescent lamp. There is a small amount of mercury and an inert gas (typically argon) in the tube, kept under very low pressure. Also, the tube has some phosphor powder, which is coated along the inside of the glass. Two electrodes are in the tube(one at each end), wired to an electrical circuit.
Then the electrical circuit will be hooked up to an alternating current (AC) supply. Metal electrodes are coated with an alkaline earth oxide, which gives off electrons readily. Then when the electric current flows through the gas between the electrodes, the gas will be ionized and emit ultraviolet radiation. Because the inside of the tube is coated with phosphors, which can absorb ultraviolet radiation and finally fluoresce, reradiating the energy as visible light.
CFL (compact fluorescent lamps)
What is it: In terms of bulbs, CFL always refers to a compact fluorescent lamp or compact fluorescent light. The CFL is a type of fluorescent lamp generally designed to replace incandescent or halogen lamps. Usually, a CFL utilizes a curved or folded tube to fit into the space of an incandescent bulb and a compact electronic ballast in the base of a CFL.
How it works: Compact fluorescent lamps (CFL) are functionally identical to standard fluorescent bulbs. CFLs are also gas-discharge lamps, using electricity from cathodes to excite mercury vapor within the glass envelope. The phosphors and inert gas are also contained within the glass envelope. When the mercury atoms release the UV light, it will lead to the fluorescence and glowing of the phosphor; finally, the visible light will be produced.
LED (light emitting diode)
What is it: LED, standing for the light emitting diode, is a semiconductor device. LED bulbs are currently one of the most energy-efficient lightbulbs. Also, when compared to other bulbs, LED ones produce no heat and have no mercury. Most importantly, LED bulbs consistently outperform other bulbs in light quality, dimming response and color rendering.
How it works: LEDs are semiconductor light sources which combine a P-type semiconductor (larger hole concentration) with an N-type semiconductor (larger electron concentration). Applying a sufficient forward voltage will cause the electrons and holes to recombine at the P-N junction, releasing energy in the form of light. LEDs bulbs are famous for their energy efficiency; in other words, they use less energy when producing light; because they can directly convert energy into light. Unlike other conventional light sources, they will convert energy into heat at first and then light.
Lumens Vs Watts
Most of you might be confused about the difference between lumens and watts in LED lighting. In the past days, watts are what we are all used to seeing on conventional bulb packagings, such as incandescent bulbs and halogen bulbs. So how do we compare lumens to watts?
The truth is that they measure different things. Watts refers to how much energy the light bulb uses, while lumen indicates the light bulb's brightness or the light output of a light bulb. Watts does not tell you how bright the bulb is, but lumens do.
What are watts?
Watts usually suggests the amount of energy consumption. Specifically, when we pay our electric bill, we pay for the watts we use. For example, a 60-watt bulb consumes 60 watts of energy. Therefore, it is evident that watts only deal with the energy or electricity consumed.
The advancement of LED technology allows bulbs to create more light with fewer watts, so wattage ratings are no longer helpful. Instead, we need to use lumens.
What are lumens?
Lumens are the only accurate measurements of light bulb brightness. Lumens measure the amount of light output from a light source and can tell you how the light performs, regardless of the light source. The higher the lumens, the brighter the light. For example, you can imagine 1 lumen is equal to the amount of light put out by one birthday candle one foot away from you.
What’s the Efficacy of your light bulb?
You can think about the miles-per-gallon in a car, so in terms of LED bulbs, we have a new measure of how well light can convert energy(watts) into light(lumens). In other words, this lumens-per-watt rating will tell you how energy-efficient your light bulb is.
LEDs are around 7 times more efficient at producing light than those conventional incandescent bulbs. Take incandescent bulbs as an example, which have only efficacy of about 15 lumens/watt. But it varies from the bulb and the manufacturer; at the same time, LED bulbs typically produce 75-110 lumens/watt. When shopping for an LED bulb to replace an incandescent bulb, try using the 7:1 ratio as a rough guide.
Do You Know about Color Temperature?
Sourcing suitable light bulbs isn't only about the brightness levels but also the lighting colors of the bulbs, which means the color temperature. Now, most lighting fixtures are produced in various color temperatures. The color of your light can significantly influence your mood. The yellowish light at night will make you feel relaxed and comfortable; the solid white light in those shopping malls will make you feel energetic and excited.
So what is color temperature?
The color temperature usually refers to ''CT'' in lighting jargon, which is a term for how warm (yellow) or cool (blue) the color of light emitted from an LED bulb shows. Color temperature is indicated as degrees Kelvin, noted by the symbol K (K); it's on a scale of 1,000 to 10,000.
2200-2700K: produces a warm light that’s best for low-light areas where ambient lighting is needed – similar to an incandescent bulb.
3000-3500K: produces a soft white light that’s crisper than 2700K, similar to halogen lamps.
4000-4500K: produces a bright white light that’s ideal in kitchens, offices, workspaces and vanities where detail-oriented tasks are performed.
5000K and up: produces a bright bluish hue of light, mostly found in commercial locations.
A good rule of thumb: the higher the temperature, the cooler the color. For instance, a 5500K hospital-grade bulb is cooler than a 2700K bulb you’d likely use in your living room.
Notably, the light with 1800K color temperature is called amber light. This special amber light can block 99.99% of blue light and protect your eyes from getting eye fatigue or eye strain. Plus, the amber light is highly recommended for bedtime or nighttime readers for reading in bed. Amber light facilitates your body to produce more melatonin, which signals your body to wind down for better sleep. Some of you who prefer reading in bed before sleep should choose a suitable amber book light.
In the End
There are 5 main types of light bulbs: Incandescent Bulb, Halogen Bulb (improved incandescent bulbs), Standard Fluorescent Bulb, CFL (compact fluorescent lamps), and LED (light emitting diode). Each of them holds different features and operating principles.
Different light bulbs types perform and look best in different kinds of lighting fixtures. Some offer energy savings like LED bulbs, while others, like incandescent light bulbs are more affordable. You can choose suitable light bulbs based on your needs, but don't forget to consider lumens and color temperatures.