Currently incandescent bulbs are still used because of many advantages such as cheap price, creating warm golden light, beautiful. However, incandescent bulbs have two major disadvantages: they are relatively inexpensive and have a long lifespan of only about 1000 hours. Today we often use other lamps like tubes, compact, LED ... more, because these lamps save energy.
Before 1800, people had only one way to create light, which is fire. In the mid-19th century, many households in the UK used gas to light up. The gas pipeline system has been built to the house for lighting, however, this light source is relatively weak, not enough to meet the needs of living. Especially not suitable for outdoor space.
To illuminate the wide open spaces, the electric arc lights were used at that time, but the arc lights were too bright, unsuitable for the household. Therefore, the scientists at that time sought to invent a suitable light for lighting household.
The 1802 experiment by British scientist Humphry Davy could be regarded as the beginning of the invention of incandescent bulbs. Davy gives an electric current through a very thin Platin fiber (Pt), platinum fibers become very hot and glow. Platinium fibers produce relatively weak light and do not last long, but Davy's experiment has created the premise that inspiration is needed for many inventors to continue to research and develop this idea.
Then more than 20 scientists from the UK, Russia, Belgium, France ... are involved in the research, development and finishing of incandescent bulbs. But most notably, the British scientist Joseph Swan.
Since 1850, Swan has designed a graphite-based light bulb (similar to the pencil bow we use today) to glow in a vacuum-filled glass vase. Swan uses lead graphite with high resistance, and the melting temperature is also very high. As the current flows through, the high-resistance graphite will become hot and light, but not burned due to being placed in a vacuum, with no ambient air. But charcoal has the disadvantage that the light bulb will clog to the charcoal, gradually will reduce the brightness.
By 1878, Swan gradually developed and perfected his light bulb, he used cotton to make a better filament bulb, plus the vacuum technology growing. By 1880 it was considered complete, the light bulb was used relatively popular in England since then. Swan was registered in the UK, and also set up his own company, installing light bulbs for both the government and the families in need.It was not until 1978 that Edison and his team of talented engineers officially began research on the production of light bulbs. Edison's bulb, along with his research and development team, is similar to that of Swan, which feeds the light through the filament of a light bulb in a vacuum. Edison initially used platinum to light the bulb, but it was not feasible because platinum was too expensive. Edison tested all possible materials: silk, leather, buttons, even hair, finally finding the right material - carbon fiber made from bamboo stalks.
Shortly, in late 1879, Edison succeeded and registered his invention in the United States.
In the end, Swan and Edison come to a partnership agreement, selling light bulbs in the UK.
No one can deny Edison's talent, Edison has teamed up talented people, talented engineers into a team working together to quickly create products, produce in large numbers, and bring products to everyone.
But in 1904, two Hungarian scientists, Alexander Friedrich Just and Franjo Hanaman, made great progress. They use tungsten filament bulbs, so that the lamp is much brighter, and have a higher life expectancy.
Then a few years later, scientists began injecting inert gas into the bulb, instead of vacuuming it. This helps the light bulb, which limits the evaporation of tungsten that clings to the inside of the bulb, making the bulb non-black. This is the light bulb that we are still using today.
