Wikipedia – The free encyclopaedia describes a light box as a container with several light bulbs inside and a pane of frosted glass on the top.
Light boxes like that were in common use for many years. Because of the bulbs used they generally got very hot on the glass surface. The depth of the light boxes were quite large to accommodate these bulbs. These light boxes were mainly used by photography professionals to view slides and photographic negatives.
Since the development of the fluorescent tube, light boxes can now be made without using ordinary light bulbs. This has resulted in two major advantages. The fluorescent tube is usually of a much lower wattage and hence the heat given off is much less and also the spread of light over the complete surface of the light box is much more even.
Lighting technology for light boxes has changed radically over the last few years. The fluorescent tube has become much slimmer reducing down to less than 5 mm in diameter. The new fluorescent tubes are called Cold Cathode Fluorescent Lamps – CCFL`s. Other lighting developments have resulted in the development of LED`s for lighting.
With the use of CCFL`s light boxes can be made very much thinner, in some cases as thin as 18 mm. By placing the light source- CCFL`s, on the edge of the glass and not behind it, also reduces the depth of the light box considerably. The glass or acrylic is now constructed with deflectors built into it so that when the light is placed on the edge of the glass the light will be deflected to the surface giving an even spread of light across the complete surface of the glass.
Mounting the light source on the edge of the diffused glass and because of the type of lamps used, the surface of the light box does not get hot. This then allows delicate products, such as X-rays and photographic negatives to be placed on the surface without damage. Using CCFL`s or LED`s as a light source has many other advantages including very low power consumption, some 90% less than conventional bulbs. They are almost maintenance free, lasting for 30,000 hours before replacement is necessary. The colour of the light source can also be designed to meet the requirements of the light box user.
The modern light box is now being used in many different applications, because it is ultra thin and does not get hot. For example displaying Posters in public places with a light box that gets hot would be dangerous and not allowed. The modern light box, which does not get hot, is ideal for such displays and can be seen in many shopping Malls etc. Further uses of these light boxes can be found in hospitals, galleries, art colleges and design companies.
The light box is no longer “just a light in a box,” it is now a sophisticated piece of equipment using the latest lighting technology in a very wide range of applications.
Authors : Mike Roberts
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