Tomas Edison made the first public demonstration of the electric light bulb on October 19, 1879. Artificial light is created when electrons flow through a gas or when electrical current goes through semiconducting crystals. An incandescent light bulb typically consists of a glass enclosure with vacuum containing a tungsten filament. An electric current passes through the filament, heating it to a temperature that produces light. Fluorescent tube has a special fluorescent coating on the inside, which emits light due to the ultraviolet rays produced by electrified gas atoms. Light-emitting diodes or LEDs are considered to be the first lamps with a solid luminous element (semiconductor crystals with p-n junction).
Since that experiment in 1879, the electric light bulb has become the symbol of progress, having gone all the way from an incandescent lamp to modern LEDs. Nowadays, incandescent light bulbs are banned in Europe as they use more energy than alternatives and are harmful for the environment. However, the image of this kind of a light bulb has become iconic and that is why it is a widespread element in retro and contemporary design.
To avoid eye strain you should work in a room with uniform light. The recommended difference in light levels between your workplace and the rest of the room should not exceed 10:1. The overhead lighting should be disseminated, as it will reduce harsh shadows that make our eyes feel tired. As for your workplace, the lighting here can be local and more intensive, especially if you are writing or working with small details. It is best for your eyes if the light is coming from above and slightly behind as in the natural daylight. To avoid working in the shadow of your hand, put your desk lamp opposite your drawing hand: if you are right-handed, your desk lamp should be on your left; if you are left-handed, it should be placed on your right hand side. As, it has been already mentioned above all harsh shadows on your workplace cause eye fatigue so it is better to use dome lamps.
The preferable light level at your workplace should be around 300 lux. This can be achieved by using a dome lamp with a light bulb 85W or a lamp with a light bulb 72W. Power should be halved when using LED lamps. If you are drawing or drafting, the recommended light level is 500 lux and a dome lamp with a light bulb 145W. Even if you are working with a computer monitor, you still need good lighting in the room, as sharp contrast between the screen and general light level in the room can also cause eye strain. The most suitable “working” light is white, especially if you need to see the difference between different shades and colours. However, warm dim light makes a better ambiance for an evening spent with friends. It is important to consider all these intricacies of lighting if you decide to study or work at home in order to create the best environment for you.
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