Light sources can be either natural or artificial. Sun is the primary source of natural light, and light bulbs or lamps are the artificial sources. Light is a form of electromagnetic energy that, in the case of natural light, comes from the sun as the source and, in case of artificial light, illuminates via energy from another source. No matter what the source, light has an impact on life on earth as a whole.
Properties of Natural Light
Natural light is self-generated and comes in a spectrum of colours --- the visible colours of the rays we experience. The colour spectrum contains light with shorter wavelengths near the violet on one end and light with higher wavelength near the red. Called ultraviolet and infrared rays respectively, these rays are not visible to us. The complete spectrum of light from the natural source is ideal for plant and animal life on earth. Plants and animals thrive on natural light. The darkness that follows photo activity in organisms helps rejuvenate and repair life forms at the cellular level. A moderate amount of exposure to the healthy sunlight benefits humans, as it increases one's energy and metabolism, boosts the immune system and helps build vitamin D --- all of which are essential for the body. Overexposure, on the other hand, has detrimental effects on living organism. The harmful ultraviolet rays can cause conditions such as skin cancer and cataracts while also damaging the texture of the skin. For plants, the need for light and dark periods helps balance the cell activity in terms of growth and repair. Sunlight is also harmful since we cannot alter or control it to suit our condition.
Properties of Artificial Light
Artificial light is man-made light generated from another energy source. Most of our activities would come to a halt if we didn't have an alternate source of light. The advantage with this light lies in the fact that we can control it at our own will. We can monitor the intensity, quantity and quality of light to suit each situation. Artificial light does not have as broad a spectrum of colours and wavelengths as natural light; hence, it is not as beneficial. Since the light has comparatively poorer quality, its effect on plant and animal life is also not as beneficial. Plants and animals exposed for prolonged periods to artificial light tend to yield poorer quality of life forms in plants and cause cellular degeneration or death in living beings.
Differences Between Natural and Artificial Light
Natural light consists of electromagnetic energy generated from the source; it contains a healthy spectrum of colours and wavelengths well suited for life on earth. Artificial light uses another energy source to generate light that is not as versatile as natural light and has a detrimental effect on plant and animal life when exposed for prolonged periods. Moderate exposure to all aspects of natural light is ideal for most life on earth; the same does not apply to artificial light, which generally serves a purpose of illumination during darkness.
Benefits of Natural Light
Natural light radiates a perfect blend of colours. An adequate amount of exposure to the invisible rays is also a healthy way for plants and animals to thrive. The intensity and the range of radiation that life forms receive from natural light are hard to mimic in an artificial setting. The alternating cycles of day and night help plant and animals perform cellular rejuvenation and repair which is essential for proper functionality.