Ceiling Fixtures are designed to give overall illumination to a room. By the time the light travels the distance from the ceiling fixture to table level, it becomes unfocused and too dim for seeing small details. The adjustable-arm allows you to direct the light in the best position to meet your particular seeing needs. For example, if you require more intense light for a task, you can move the light closer. Also, the adjustable-arm allows you to position the angle of light in such a way to eliminate glare.
Illuminated magnification is the combination of a magnifying lens with a light source.
There is a wide variety in the type and quality of both the magnifying lens and light source. Magnifying lenses come in numerous sizes and powers, with some having less distortion than others. Proper lighting is equally important as magnification in achieving a good viewing situation. A magnifying lens would be useless in the dark, so increasing light levels results in better vision. The better the quality of light used with a magnifying lens, the less magnification power is needed.