Illumination
Standard Bulbs
These are relatively inexpensive and easy to obtain. When used in
a directional unit such as an anglepoise lamp, a 60 watt bulb is
usually sufficient. Principal drawbacks of this type of bulb are
the ‘yellow light’ they produce and the amount of heat they generate.
Daylight Bulbs
These bulbs are similar to standard bulbs but have a filter coating
which produces a light of similar colour temperature to daylight.
As with normal bulbs a 60 watt unit should be more than sufficient.
Halogen Bulbs
Utilising differing gases within the bulb to produce light, halegon
bulbs produce a very bright, white light that is particularly effective
for near vision tasks. Whilst the actual bulb does get quite warm,
halogen units tend to be cooler in use than an equivalent standard
bulb. Principal drawbacks with halogen bulbs tend to be the relatively
narrow beam of light they produce.
Fluorescent Bulbs
By using phosphorescent coatings inside the tube, fluorescent lights
can produce light of varying colour temperatures, ranging from a
warm yellow sodium colour through to the cooler blue-white daylight
equivalent.
Fluorescent tubes produce a very even illumination
and have the advantage of offering a good spread of light making
them ideal for general reading tasks. Due to the nature of the light
produced, fluorescent units tend to be quite cool allowing for the
lamp to be placed quite close to the user.
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