The human need has emerged since prehistoric times to fill the lack of natural lighting with artificial lighting, so he used fires, torches, candles, lamps, and others. Illumination techniques have developed with the development of man’s ability to control fire and access sources of lighting with great effectiveness and efficiency and find the appropriate means to control it. Starting with the adjustable cotton wick fueled by oxygen needed for combustion, through the kerosene as a lighting fuel and paraffin oil to the natural gas at the beginning of the 19th century. In the middle of the 19th century, the discovery of electricity by Thomas Edison changed human lives. The layout of lighting should take into account its function and intended purpose. There are agreed rates and controls when designing the lighting of a place.

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The history of lighting _ ©

What is The Spectrum of Light?

Light spectrum (also known as an electromagnetic spectrum) is a term used to describe the range of light that exists, measured in nanometers (nm). More frugally, this range of wavelengths is called visible light. Generally, the human eye can detect wavelengths from 380 to 700 nanometers. Nonetheless, most of the light in the universe is invisible to us. Light is an energy and comes in many different wavelengths, known as the lightwave spectrum. Noteworthy is that visible light is not the only type of electromagnetic spectrum. It is the one form the eye can realize. As cone-shaped cells in our eyes act as receivers tuned to the wavelengths in this narrow band of the spectrum. Other parts of the spectrum have wavelengths too large or too small and energetic for the biological limitations of our perception. For instance, infrared, UV-Light, X-Rays, Gamma Rays, and Cosmic Rays are also part of the electromagnetic waves spectrum. 

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The Spectrum of light _ ©

What are The Colors of the Visible Light Spectrum?

On the point the full spectrum of visible light travels through a prism, the wavelengths separate into the colors of the rainbow because each color is a different wavelength. Respectively described by the term “Roy G. Biv” Red, Orange, Yellow, Green, Blue, Indigo, and Violet are the colors visible to us. Violet has the shortest wavelength, almost 380 nanometers. Red has the longest wavelength, almost 700 nanometers.

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The visible spectrum of light _ ©

Benefits of Light Spectrum 

Studies have proven that light, whether it be natural or artificial, provides many health benefits. For instance, natural sunlight has proven to boost immunity levels, improve overall wellness, boost vitamin d levels, low energy levels, and other light deprivation-related conditions. In this case, light therapy uses either full spectrum or blue light to trigger serotonin and melatonin production in the body. These hormones are the main key to mood regulation, sleep-wake cycles, and overall energy levels. In addition, Low-Level Light Therapy (also known as LLLT) is a fast-growing technology used to treat many conditions, especially skin, pain relief, and injury recovery.

The Color Rendering Index (CRI)

The eye sees all objects as reflected light. All of the colors in the object must also be present in the beam of light to directly reproduce the image in reflected light. The Color Rendering Index is a numerical scale from zero to one hundred used to rate the accuracy of colors that can be distinguished under a light source. A value of 100 (CRI) indicates perfect color rendering. There is, even so, another factor to consider in the color equation, the amount of light. Low light levels cause an object to lack color and appear dull or grayish.

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The Color Rendering Index _ ©

Factors to be Considered for Good Lighting  

Scientific research has proved that light has a huge effect on the surrounding environment, it can transform space and affect your mood and energy. Lighting design is a vital element of any space. Understanding the physical and psychological properties of light is essential in designing any space. Visual comfort is related to the ease of seeing the task, which includes the same factors as visual competence. Visual comfort is very personal; it is a matter of feelings and perceptions. It is measured by a rather vague criterion called the “visual comfort probability”. The most important factors in visual quality that can form a healthy environment are:

1. Light intensity in the area of interest

In particular, high levels of illumination increase the efficiency of tasks but cause discomfort. Appropriate lighting levels depend on the size and contrast of details displayed, the age of the viewer, and other factors.

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The light intensity around the bookshelves and the research area_ ©

2. Illumination uniformity

The uniformity of task lighting is important for visual comfort, although the effect cannot be measured precisely. Choosing between different color temperatures of light whether it’s cold or warm according to the activity in the space.

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Color temperature _ ©

3. Forming shadows

Shadows within the viewed material are needed to provide contrast for visual efficiency, but shades of excessive coverage in the viewing area reduce visual quality.

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Forming shadows _ ©

4. Background lighting

Backlighting outside the direct area of the task, that’s what you see from the corner of your eye. The observation shows how background lighting affects visual efficiency and visual comfort, as well as its impact on aesthetics.

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Background lighting _ ©

5. Glare from the light source

Glare from light sources can seriously impair visual comfort. The observation shows how this can affect the quality of the indoor environment.

6. Veiling reflections

Veil reflections reduce visual efficiency by reducing contrast, cause discomfort by making it more difficult to see, and waste energy.

7. Color rendering

Lighting is a vital element in our lives, you wouldn’t stand much time without light.      Architectural lighting is illumination for building design and function, as Norman Foster said: “Architecture is an expression of values”. Lighting with the exterior and interior architecture design narrates, highlights, and completes the artwork. According to the architect Michael Munson “exaggerate certain architectural features, provide intimacy, create excitement, et cetera”


  1. Tour of the Electromagnetic Spectrum (2022). NASA SCIENCE ( Last updated 9.Sep.2022) available at: [Accessed 9.Sep.2022].
  2. General Lighting Basics (2022). EYE Lighting Institute. (Last updated 26.May.2022) available at:  [Accessed 9.Sep.2022].
  3. UNDERSTANDING THE LIGHT SPECTRUM AND ITS BENEFITS (2022). Carex Health (Last updated 2022) available at:  [Accessed 9.Sep.2022].

I'm an architect who truly curious, open-minded person who is keen on travel and explore the world , its cultural traditions ,its people and its architecture .I always believed that good architecture is like a good cup of coffee or a wonderful painting which can be a piece of heaven .

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