Whelen Lights

Bulb Out

How LED Light Bulbs Are Made

One-hundred-and-thirty years ago, Thomas Edison completed the first successful sustained test of the incandescent light bulb. With some incremental improvements along the way, Edison’s basic technology has lit the world ever since. This is about to change. We are on the cusp of a semiconductor-based lighting revolution that will ultimately replace Edison’s bulbs with a far more energy-efficient lighting solution. Solid state LED lighting will eventually replace almost all of the hundreds of billions of incandescent and fluorescent lights in use around the world today. In fact, as a step along this path, President Obama last June unveiled new, stricter lighting standards that will support the phasing out of incandescent bulbs (which already are banned in parts of Europe).

To understand just how revolutionary LED light bulbs are as well as why they are still expensive, it is instructive to look at how they are manufactured and to compare this to the manufacture of incandescent light bulbs. This article explores how incandescent light bulbs are made and then contrasts that process with a description of the typical manufacturing process for LED light bulbs.

So, let’s begin by taking a look at how traditional incandescent light bulbs are manufactured. You will find that this is a classic example of an automated industrial process refined in over a century of experience.

While individual incandescent light bulb types differ in size and wattage, all of them have the three basic parts: the filament, the bulb, and the base. The filament is made of tungsten. While very fragile, tungsten filaments can withstand temperatures of 4,500 degrees Fahrenheit and above. The connecting or lead-in wires are typically made of nickel-iron wire. This wire is dipped into a borax solution to make the wire more adherent to glass. The bulb itself is made of glass and contains a mixture of gases, usually argon and nitrogen, which increase the life of the filament. Air is pumped out of the bulb and replaced with the gases. A standardized base holds the entire assembly in place. The base is known as the “Edison screw base.” Aluminum is used on the outside and glass used to insulate the inside of the base.

Originally produced by hand, light bulb manufacturing is now almost entirely automated. First, the filament is manufactured using a process known as drawing, in which tungsten is mixed with a binder material and pulled through a die (a shaped orifice) into a fine wire. Next, the wire is wound around a metal bar called a mandrel in order to mold it into its proper coiled shape, and then it is heated in a process known as annealing, softening the wire and makes its structure more uniform. The mandrel is then dissolved in acid.

Second, the coiled filament is attached to the lead-in wires. The lead-in wires have hooks at their ends which are either pressed over the end of the filament or, in larger bulbs, spot-welded.

Third, the glass bulbs or casings are produced using a ribbon machine. After heating in a furnace, a continuous ribbon of glass moves along a conveyor belt. Precisely aligned air nozzles blow the glass through holes in the conveyor belt into molds, creating the casings. A ribbon machine moving at top speed can produce more than 50,000 bulbs per hour. After the casings are blown, they are cooled and then cut off of the ribbon machine. Next, the inside of the bulb is coated with silica to remove the glare caused by a glowing, uncovered filament. The label and wattage are then stamped onto the outside top of each casing.

Fourth, the base of the bulb is also constructed using molds. It is made with indentations in the shape of a screw so that it can easily fit into the socket of a light fixture.

Fifth, once the filament, base, and bulb are made, they are fitted together by machines. First, the filament is mounted to the stem assembly, with its ends clamped to the two lead-in wires. Next, the air inside the bulb is evacuated, and the casing is filled with the argon and nitrogen mixture.

Finally, the base and the bulb are sealed. The base slides onto the end of the glass bulb such that no other material is needed to keep them together. Instead, their conforming shapes allow the two pieces to be held together snugly, with the lead-in wires touching the aluminum base to ensure proper electrical contact. After testing, bulbs are placed in their packages and shipped to consumers.

Light bulbs are tested for both lamp life and strength. In order to provide quick results, selected bulbs are screwed into life test racks and lit at levels far exceeding normal. This provides an accurate measure of how long the bulb will last under normal conditions. Testing is performed at all manufacturing plants as well as at some independent testing facilities. The average life of the typical household bulb is 750 to 1,000 hours, depending on wattage.

LED light bulbs are built around solid-state semiconductor devices, so the manufacturing process most closely resembles that used to make electronic products like PC mother boards.

A light-emitting diode (LED) is a solid state electrical circuit that generates light by the movement of electrons in a semiconductor material. LED technology has been around since the late 1960s, but for the first 40 years LEDs were primarily used in electronics devices to replace miniature light bulbs. Within the last decade, advances in the technology finally boosted light output high enough for LEDs to begin to seriously compete with incandescent and fluorescent light bulbs. As with many technologies, as the cost of production falls each successive LED generation also improves in light quality, output per watt, and heat management.

The computer industry is well suited to manufacture LED lighting. The process isn’t a whole lot different than making a computer motherboard. The companies making the LEDs themselves are generally not in the lighting business, or it is a minor part of their business. They tend to be semiconductor houses that are happy cranking out their product, which is why prices on high-output LEDs has fallen so much in the last 15 years.

LED bulbs themselves are expensive in part because it takes a number of LEDs to get wide-area illumination instead of a narrow beam, and the assembly cost adds to the overall price. In addition, assemblies consisting of arrays of LEDs create more opportunities for product defects.

An LED light consists of four essential components: an LED circuit board, a heatsink, a power supply, and a shell. The lights start out as bare printed circuit boards (PCB) and high luminance LED elements arrive from separate factories which specialize in making those components. LED elements themselves create a bit of heat, so the PCB used in lighting fixtures is special. Instead of the standard non-conductive sandwich of epoxy and fiberglass, the circuit board is laid out on a thin sheet of aluminum which acts as a heatsink.

The aluminum PCB used in LED lighting is coated with a non-conducting material and conductive copper trace lines to form the circuit board. Solder paste is then applied in the right places and then Surface Mount Technology (SMT) machines place the tiny LED elements, driver ICs, and other components onto the board at ultra high speeds.

The round shape of a traditional light bulb means that most LED printed circuit boards are circular, so for ease of handling several of the smaller circular PCBs are combined into one larger rectangular PCB that automated SMT machinery can handle. Think of it like a cupcake tray moving from one machine to the next along a conveyor belt, then at the end the individual cupcakes are snapped free from the tray.

Let’s take a look at the manufacturing steps for a typical LED light bulb meant to replace a standard incandescent bulb with an Edison Screw. You will see that it is a very different process from the highly automated processes used to manufacture our familiar incandescent bulbs. And, despite what you might imagine, people are still very much a necessary part of manufacturing process, and not just for testing and Quality Assurance either.

Once the larger sheets of LED circuit boards have passed through a solder reflow oven (a hot air furnace that melts the solder paste), they are broken up into the individual small circuit boards and power wires manually soldered on.

The small power supply housed in the body of the light bulb goes through a similar process, or may be delivered complete from another factory. In either case, the manufacturing steps are the same; first the PCB passes through SMT lines, then it goes to a manual dual in-line package (DIP) assembly line where a long row of factory workers add one component at a time. DIP refers to the two parallel rows of leads projecting from the sides of the package. DIP components include all integrated chips and chip sockets.

While LED lights burn several times longer than incandescent or CFLs and require less than half the energy, they need some form of passive heatsink keep the high-power LEDs from overheating. The LED circuit board, which is made from 1.6-2mm thick aluminum, will conduct the heat from the dozen or so LED elements to the metal heatsink frame and thus keep temperatures in check. Aluminum-backed PCBs are sometimes called “metal core printed circuit boards,” and though made of a conductive material the white coating is electrically isolating. The aluminum PCB is screwed in place within the heatsink which forms the lower half of the LED light bulb.

After this, the power connector board is fixed in place with adhesive. The small power supply converts 120/240V AC mains power to a lower voltage (12V or 24V), it fits in the cavity behind the aluminum PCB.

Shell assembly consists of locking the shell in place with screws. A plastic shell covers the power supply and connects with the metal heatsink and LED circuit board. Ventilation holes are included to allow hot air to escape. Wiring assembly for plug socket requires soldering wires to the bulb socket. Then shell is attached.

Next, the completed LED light is sent to burn-in testing and quality control. The burn-in test typically lasts for 30 minutes. The completed LED light bulb is then powered up to see if it is working properly and burned in for 30 minutes. There is also a high-voltage leakage and breakdown test and power consumption and power factor test. Samples from the production run are tested for high-voltage leaks, power consumption, and power factor (efficiency).

The finished bulbs pass through one final crimping step as the metal socket base is crimped in place, are bar-coded and identified with lot numbers. External safety labels are applied and the bulb is inked with information, such as brand and model number. Finally, all that’s left is to fix on the clear plastic LED cover which is glued in place.

After a final check to make sure all the different parts of the LED light are tight, then it is packed into individual boxes, and bulbs are shipped out.

So, if you have wondered why LED light bulbs are so expensive today, this explanation of how they are manufactured and how that compares to the manufacture of traditional light bulbs should help. However, it also reveals why the cost will fall pretty dramatically over the next few years. Just as the cost of manufacturing other semiconductor-based products has fallen dramatically due to standardization, automation and other key steps along the manufacturing learning curve, the same inexorable forces will drive down the costs of LED light bulb production.

For practical advice about LED lights, including everything you ever wanted to know about LED tube lights, please visit ledtubelights.org and for objective reviews of LED lighting products, please visit LED Light Reviews.

About the Author

James is a small business owner who enjoys sharing the lessons he has learned retrofitting his office and home with energy-efficient LED lighting. In fact, he likes LED lights so much, that he has become sort of an LED lighting evangelist. For practical advice about LED lights, including everything you ever wanted to know about LED tube lights, please visit ledtubelights.org.

Bulb $10.49 Bulb

Bulb (Hardcover) $62.05 In this stunning guide that is both scholarly and practical, Anna Pavord, "the tulip lady," chooses her favorite bulbs, rumors, and corms-more than 500 of them-and tells you exactly how to grow them. The rarely seen English iris, the snakeshead fritillary, a speckled apricot lily, an amazing tricolored crocus....If you can tear yourself away from the photographs, there`s no way you won`t want to get out into the yard with a trowel, a bag of bonemeal, and a bag of glorious bulbs, ready to plant.

50W-100W-150W,3 Way Bulb Bulb: HF $10.34 Ordinary light bulbs that most of us use cast a greenish-yellow hue that distorts colors as well as textures, and stress our eyes. Chromalux Full Spectrum "Color Correct" bulbs are made in France to the highest standards using pure Neodymium glass that filters out the excessive yellow part of the spectrum, and purifying all colors. Chromalux Color correct bulbs specifications: * Chromed brass socket to prevent corrosion * Long life, averaging 4000 to 5000 hours * Interior or exterior frosting depending on type Balanced light is critical to the creation and presentation of objects of art. Years of research in Finland resulted in the design of this unique light source which closely mimics natural light, producing a more balanced and pure white light. Under Chromalux, matching, mixing as well as viewing colors becomes an easy task. Chromalux color correct bulbs are available in the following types and wattages and can retrofit existing fixtures. Install Chromalux full spectrum natural lighting in your studio and witness the amazing difference!

AC-7014 Replacement UV bulb $72.74 This SPT replacement UV bulb sterilizes the air by breaking down microorganisms. This UV bulb effectively destroys the nucleic acids so their DNA is disrupted and destroyed. Replace when bulb is outWorks for models AC-7014W (item: 13534430) and AC-7014G (item: 13534433)Dimensions: 12 inches long x 0.69 inches wide x 0.69 inches deep

Sunpentown LAMP7014 AC7014 UV Bulb $41.08 This SPT replacement UV bulb sterilizes the air by breaking down microorganisms. This UV bulb effectively destroys the nucleic acids so their DNA is disrupted and destroyed. Replace when bulb is out. Works for models AC7014W and AC7014G. Dimensions: 12 L x 0.69 W x 0.69 D.

Desert Coil Bulb - 20W $24.99 Add beneficial UVB lighting to your reptile's terrarium without the hassle of buying a large reptile terrarium lighting system. The Desert Coil Compact Fluorescent Bulb fits into any standard incandescent socket and provides 12-months worth of intense UVA & UVB rays to your reptile pet. The 50 microwatt/sec. output is sufficient for the most desert-loving reptile species. Also provides UVA light to bring out the most vivid coloration in your pet.

Greenlite H13 Halogen Bulb $11.95 The Greenlite H13 Halogen Bulb has a double filament technology that not only assures more light output, but also ensures with the 5 axis focus design - a focused and accurate beam eliminating stray and uncontrolled light, thereby reducing the glare for oncoming drivers. The H13 bulbs unique seal-off system totally keeps out foreign elements like dust fumes and moisture.     Specifications: Wattage: 60/55W Voltage: 12V Lumens: 1700 Base Type: P26.4t Life (hours): 600

CCA light bulb TeeCZee Light bulb Dark T-Shirt by CafePress $26 CCA light bulb tee Light bulb Dark T-Shirt Tee, TShirt, Shirt Don't waste time deciding on which shirt to put on each morning. This dark shirt t-shirt will never go out of style and hides stains better too. This high-quality t-shirt is pre-shrunk and 100% cotton, which makes it both comfortable and durable.

Big Bulb Multi-Color Lights $44.99 Big Bult Multi-Color Lights set measures approximately 14' long and has a white power cord (2' long). Includes (20) clear lights with 3.5" multi-colored globes (plastic). Set is UL Listed. Can be used indoors or outdoors. Has an end to end plug to attach additional light sets (other light sets are sold separately). Lights burn steady and do not flash. Includes (1) extra bulb and (1) extra fuse. If one bulb burns out,the others remain lit.

Light Bulb Std Clear 75W Bulb: HF $7.64 Ordinary light bulbs that most of us use cast a greenish-yellow hue that distorts colors as well as textures, and stress our eyes. Chromalux Full Spectrum "Color Correct" bulbs are made in France to the highest standards using pure Neodymium glass that filters out the excessive yellow part of the spectrum, and purifying all colors. Chromalux Color correct bulbs specifications: * Chromed brass socket to prevent corrosion * Long life, averaging 4000 to 5000 hours * Interior or exterior frosting depending on type Balanced light is critical to the creation and presentation of objects of art. Years of research in Finland resulted in the design of this unique light source which closely mimics natural light, producing a more balanced and pure white light. Under Chromalux, matching, mixing as well as viewing colors becomes an easy task. Chromalux color correct bulbs are available in the following types and wattages and can retrofit existing fixtures. Install Chromalux full spectrum natural lighting in your studio and witness the amazing difference!

Light Bulb Std Clr 3Way Bulb: HF $11.69 Ordinary light bulbs that most of us use cast a greenish-yellow hue that distorts colors as well as textures, and stress our eyes. Chromalux Full Spectrum "Color Correct" bulbs are made in France to the highest standards using pure Neodymium glass that filters out the excessive yellow part of the spectrum, and purifying all colors. Chromalux Color correct bulbs specifications: * Chromed brass socket to prevent corrosion * Long life, averaging 4000 to 5000 hours * Interior or exterior frosting depending on type Balanced light is critical to the creation and presentation of objects of art. Years of research in Finland resulted in the design of this unique light source which closely mimics natural light, producing a more balanced and pure white light. Under Chromalux, matching, mixing as well as viewing colors becomes an easy task. Chromalux color correct bulbs are available in the following types and wattages and can retrofit existing fixtures. Install Chromalux full spectrum natural lighting in your studio and witness the amazing difference!

Light Bulb,Clear 60W 60W Bulb: HF $6.92 Ordinary light bulbs that most of us use cast a greenish-yellow hue that distorts colors as well as textures, and stress our eyes. Chromalux Full Spectrum "Color Correct" bulbs are made in France to the highest standards using pure Neodymium glass that filters out the excessive yellow part of the spectrum, and purifying all colors. Chromalux Color correct bulbs specifications: * Chromed brass socket to prevent corrosion * Long life, averaging 4000 to 5000 hours * Interior or exterior frosting depending on type Balanced light is critical to the creation and presentation of objects of art. Years of research in Finland resulted in the design of this unique light source which closely mimics natural light, producing a more balanced and pure white light. Under Chromalux, matching, mixing as well as viewing colors becomes an easy task. Chromalux color correct bulbs are available in the following types and wattages and can retrofit existing fixtures. Install Chromalux full spectrum natural lighting in your studio and witness the amazing difference!

Tracer Bulb Repl UV120w 1200. Each $150.06 Manufacturer: Tracer Products. Each. New out of box defects "30d warranty" Customers also search for: Discount Bulb Repl UV120w 1200, Buy Bulb Repl UV120w 1200, Wholesale Bulb Repl UV120w 1200, 672052161857, TP-1210, Light Bulbs

Tracer Replacement Bulb, 50w, 12v. Each $37.47 Manufacturer: Tracer Products. Each. New out of box defects "30d warranty" Customers also search for: Discount Replacement Bulb, 50w, 12v, Buy Replacement Bulb, 50w, 12v, Wholesale Replacement Bulb, 50w, 12v, 672052200938, TP-8115, Light Bulbs

Ultrafire WF-500 Replacement Xenon Bulb Module $4.5 - Replaces the Xenon bulbs in Ultrafire WF-500> flashlights- Just swap out your burnt out bulb with this one and you're doneSpecificationsDimensions: 1.38 in x 0.79 in x 0.79 inWeight: 0.28 oz

The Art and Science of Light Bulb Moments $9.99 The Art and Science of Light Bulb Moments is an interactive, educational and entertaining guide on how to have ideas on demand. Tom Evans explains how the mind works (and doesn't work) so you that you can experience inspirations about anything pretty much any time you like. Light bulb moments don't have to be random. You will learn the secrets to Whole Brain and Whole Mind Thinking, the importance of the breath and how to reconnect with your vestigial minds and the superconsciousness. Find out where ideas come from and why most thoughts aren't necessarily your own. Reading this book will quite possibly change your world by helping you spot serendipities, making you luckier and even healthier and wealthier.

Floresta Set of 3 Bulb Vases - Twos Company $56 Floresta Set of 3 Bulb Vases - Twos Company Floresta Set of 3 Bulb Vases Includes 3 Shapes/Colors: Pink, Blue, Green - Glass . from 3" x 4 1/2" H to 3 1/2" x 5" H 1-2 business days to ship out and receive tracking.

I, Light Bulb with Bonus eBook $1.99 New from Broadside Books' Voices of the Tea Party. I , Light Bulb: A Death Row Testimonial as told to Michael Patrick Leahy, demonstrates how the American economy has gone from free markets to politically correct, government controlled crony capitalism in the half century since Leonard E. Read wrote the classic essay I, Pencil. Leahy tells the story of the ban on the current generation of incandescents from the perspective of a condemned 100 watt light bulb. In the voice of the light bulb, Leahy points out the need for political activism to reverse this ban, arguing that it not onlyprevents an innocent incandescent light bulb from continuing a useful economic life, it also deprives every American of their own economic liberty and freedom of choice. Readers who buy I, Lightbulb will also receive the bonus companion e-book The Disastrous Lightbulb Ban by Howard Brandston, at no additional cost. Brandston, the internationally recognized expert on lighting most well known for lighting the Statue of Liberty, explains why the federal government's ban on the current generation of incandescent light bulbs is such a bad idea. He explains how in 2007 a Democrat controlled Congress, the lamp manufacturers, the Department of Energy, and George W. Bush combined to force us to replace inexpensive and safe incandescent light bulbs with expensive, unsafe Compact Fluorescent Light bulbs that contain mercury. In this companion book to I, Light Bulb, Brandston concludes by encouraging citizen political activism to repeal this ridiculous ban.

Sylvania H13 Halogen Foglight Bulb $12.95 The Sylvania H13 dual-filament halogen bulb outperforms all dual-filament designs and rivals performance characteristics of many single-filament light sources. Computer-driven design, engineering, and manufacturing ensure precision filament position and facilitates consistent beam patter. It's robust construction is designed to withstand significant road vibration, resulting in an average life of over 1500 hours. The compact design of the H13 provides stylists with the ability to create lower-profile headlamp assemblies. Complies with all ECE and NAFTA regulations while satisfying both U.S. and European consumer priorities. Bulb is sold individually.     Features: Out performs all dual-filament designs Precision filament position and consistent beam pattern Withstands significant road vibration, resulting in an average life of over 1500 hours Fine tune sleeve system Larger locking tabs Ergonomic tabs U.S. car standard connector Enhanced gasket seal Tighter tolerance Oversized "boot" retaining flange One-piece base   Not Sure Which Lights Your Vehicle Uses? Find the right light number for your vehicle here -----> CLICK HERE

25 Watt A19 Loop Series Bulb by Bulbrite $14 Add a gentle nostalgic glow to lighting fixtures with the Bulbrite 25 Watt A19 Loop Series Bulb. The clear glass bulb features a classic A-shape, medium screw base and a distinctive looped filament putting out a soft wash of light. Other wattages and filament structures are available (sold separately). Since 1971, from its headquarters in New Jersey, Bulbrite manufactures and supplies an extensive line of innovative and award-winning light bulbs. Their line of energy efficient light source solutions, educational resources and outstanding service make Bulbrite the bulb supplier of choice for lighting professionals. The Bulbrite 25 Watt A19 Loop Series Bulb is available with the following: Details:Type A19 Clear incandescent bulbMedium (E26) base25 watts120 volts50 lumensAverage Rated Life: 3000 hoursDimmableShipping: This item usually ships in one business day. Dimensions: Bulb: Length 4.5 In.

Respironics Bulb-Style Syringe Nasal Aspirator, 24/Bx $66.99 Bulb-Style Syringe Nasal Aspirator This safe, easy-to-use nasal aspirator provides gentle suction to remove excess mucus or secretions from a baby’s nasal passage. The First Years® bulb-style aspirator, an officially-licensed product of the American Red Cross, features an over-insertion guard and a pull-out plug that allows thorough cleaning. Children’s Medical Ventures is pleased to be the exclusive provider of this pediatrician-approved nasal aspirator to hospitals.

Respironics Bulb-Style Syringe Nasal Aspirator, Each $4.99 Bulb-Style Syringe Nasal Aspirator This safe, easy-to-use nasal aspirator provides gentle suction to remove excess mucus or secretions from a baby’s nasal passage. The First Years® bulb-style aspirator, an officially-licensed product of the American Red Cross, features an over-insertion guard and a pull-out plug that allows thorough cleaning. Children’s Medical Ventures is pleased to be the exclusive provider of this pediatrician-approved nasal aspirator to hospitals.

Desert Reptile Fluorescent Bulb - 12W - 20 in. - T-5 $12.99 Intense desert T5 fluorescent bulb provides your desert-dwelling reptile the essential UVB it requires for proper calcium absorption. Bearded dragons and other hot-weather species thrive under the glow of these powerful lamps. Also provides UVA rays to bring out your pet's best side.

Desert Reptile Fluorescent Bulb - 14W - 24 in. - T-5 $12.99 Intense desert T5 fluorescent bulb provides your desert-dwelling reptile the essential UVB it requires for proper calcium absorption. Bearded dragons and other hot-weather species thrive under the glow of these powerful lamps. Also provides UVA rays to bring out your pet's best side.

Desert Reptile Fluorescent Bulb - 18W - 30 in. - T-5 $13.89 Intense desert T5 fluorescent bulb provides your desert-dwelling reptile the essential UVB it requires for proper calcium absorption. Bearded dragons and other hot-weather species thrive under the glow of these powerful lamps. Also provides UVA rays to bring out your pet's best side.

Desert Reptile Fluorescent Bulb- 21W - 36 in. - T-5 $15.89 Intense desert T5 fluorescent bulb provides your desert-dwelling reptile the essential UVB it requires for proper calcium absorption. Bearded dragons and other hot-weather species thrive under the glow of these powerful lamps. Also provides UVA rays to bring out your pet's best side.

Desert Reptile Fluorescent Bulb - 28W - 48 in. - T-5 $17.89 Intense desert T5 fluorescent bulb provides your desert-dwelling reptile the essential UVB it requires for proper calcium absorption. Bearded dragons and other hot-weather species thrive under the glow of these powerful lamps. Also provides UVA rays to bring out your pet's best side.

125 watt Fluorescent Bulb 6500K: HY $77.95 125 watt fluorescent bulb. Great for burning next to your HPS lamp to give more blue light(badly needed for all hps bulbs). It will really put the zing back into your bloom experience. Or, burn one or more by themselves. Low heat makes it a perfect choice for high temp areas. Vegetation grade bulb. Screws into common mogul base sockets. Puts out about the same light as a 175-250 watt metal haliade 6.4K color output. Great for vegatative growth. The ballast must be disconnected and and wired 120 volts to the bulb. You can not just screw this bulb in to your existing ballast powered reflector. You will blow up the lamp. HPS / MH bulbs take higher than 120 volts to fire. The lamp is shown in the re400 series horizontal reflectors. A mogul base socket and 110 volt power connection was installed onto the reflector.