History of Light
Today, we take the existence of light for granted. But what was the world like when light was created? New answers to this question have been given by the European Planck satellite. It has made the most detailed observations so far of the afterglow from the Big Bang – the very first light that filled the Universe
"Without light, no life"
The first light
The Big Bang occurred almost 14 billion years ago, when the infinite universe was born in a very hot and dense state. Immediately, the universe began to expand, lowering both the temperature and the density – a process that is still continuing today. In the first few minutes after the Big Bang, the fundamental building blocks of our world where formed: protons, neutrons and electrons.
The first light was set free some 380,000 years after the Big Bang, when it decoupled from ordinary matter particles. The cosmic background radiation has existed ever since, filling the entire universe. Only its wavelength has changed with the expansion of the universe. From a yellow light (similar to that of a light bulb), the cosmic background radiation has slowly shifted to microwave radiation, which is invisible to the human eye.
Read more: D/A Magazine # 19, Michael Linden-Vørnle
Development of Artificial Lighting
“Fire is the sun unwinding from the tree's log” - Buckminster Fuller
Light is one of life’s necessities. We would not be on this planet if there was no light. When there is no natural light, we need artificial. Some 400,000 BC Homo erectus finds fire, most likely by accident when a lightning hit a tree or a bush. Human development was born from that accident.
First portable light was a torch - a branch or a bundle of sticks tied together with one end doused in a flammable liquid and lit. Around 70,000 BC, the first primitive oil lamps appeared. They were made from hollow stones or shells that were filled with moss soaked with animal fat. The first candles were made in China in 200 BC from whale fat with rice paper wick. Through time they were made from other materials too, like tallow, spermaceti, colza oil and beeswax until the discovery of paraffin wax which made production of candles cheap and candles affordable to everyone. The wick was also improved over time and made from paper, cotton, hemp and flax with different times and ways of burning.
Although we had artificial light for centuries, as late as 19th century there still were no ideas for illumination of greater areas: streets, public places, factories, even of rooms in houses. Lack of natural light during nighttime in the urban environment was always a problem. The history of street light is, however, longer than we think.
It is known that natural gas was led through bamboo pipes from volcano gas leaks to the streets of Peking to serve as a fuel for street lamps as early as 500 years BC. And ancient Romans used oil lamps filled with vegetable oil in front of their houses and had special slaves whose only duty was to take care of those lamps, to light them, extinguish them and watch that they always have oil. First organized method of public lightning was done in London and Paris streets by order that said that all houses must have light in the windows at night if they face the streets.
There were tries to illuminate the streets as early as 15th century in London and Paris with orders that all houses that had street side must have a light in the window so the people could see at night. That kind of light was also not sufficient as it was weak and irregular. The real solution was hiding in the ground for thousands of years; coal gas that is found in coalmines. In 1807 in London, Pall Mall is the first street to get gaslight while Paris gets them in 1820. Gas was transported through pipes to the gas lamps and lamps were placed on the posts. After Europe gas lamps spread to America and Baltimore was a first city in the United States that got gas light in 1816 and the first city that had gas streetlights. By the beginning of 20th century, most of the cities in the Europe and America had streets illuminated by gas lamps and it remained like that until the advent of the electricity.
The first experiments in electrical illumination were made in the 19th century and a prototype of a first electric arc lamp was made in 1809 and in the years to come, many inventors experimented on the design of electric light. They changed materials of filament and tried different atmospheres inside a bulb - from better vacuum to noble gas - and the first commercially usable electric light came to market in in 1870s. At first, only few used electric lamps because of their high price but in time their use spread and it is estimated that by 1885, in the United States only, some 300.000 electric lamps were sold. Electric light spread across the world and is still here today as necessity in many variations and for indoor and outdoor purposes.
The electric gas-filled tungsten lamps came to marked in 1915; This was an incandescent lamp that used tungsten rather than carbon or other metals as a filament inside the lightbulb and became the standard. The fluorescent lamp was patented in 1927 and a tungsten halogen light in 1960. LEDs (light emitting diodes) may seem like a new technology, but experiments were noted as early as 1907 leading to be today's most rapidly-developing lighting technologies.
Daylight and windows
"A room is not a room without natural light” - Louis I. Kahn
The English language-word 'window' originates from the Old Norse `vindauga´ that can be translated to a 'wind eye'.
Not many parts of a building are as expressive and vital as windows; where the outside and inside meet - where daylight penetrate - where the view occur - and where the breeze, sounds, smells with seasonal changes, activate our senses.
In the 13th century BC, the earliest windows were smoke holes - left completely open, but to provide protection from the wind, cold, and rain, the hole was covered with wood and could be opened and closed from inside. In order to let in light, the wood was eventually replaced by frames covered with translucent material, for example parchment – a thin, light dried and polished animal skin – or very thin membranes from organs such as the bladder or the amniotic sac.
The Romans were the first known to use glass for windows, a technology likely first produced in Roman Egypt. Namely, in Alexandria ca. 100 AD cast glass windows, albeit with poor optical properties, began to appear, but these were small thick productions, little more than blown glass jars..6
Pre 16th century windows were constructed from stone mullions or timber frames with unglazed openings. They could be closed by use of sliding or folding wooden shutters, oiled cloth, paper or even thin sheets of horn. Glazed windows were used only for the highest status buildings and were constructed of small panes of glass quarrels held together in a lattice of lead strips.
While window designs have long varied in opening size, sash pattern, and shape, they remained largely made from wood until the early 20th century. Many new types of windows were developed during modernism's construction boom from 1930 to about 1950 - continuing until the 1970s - and a great many new materials were used. The most characteristic of modernist window types were thin steel windows, corner windows, and round windows inspired by ships. Curtain Wall, a non-loadbearing façade construction, also appeared during this epoch. In addition, the revolutionary float glass was developed during the period. Float glass had enormous implications for the window industry, as glass could suddenly be made in considerably larger dimensions. Also insulating windowpanes and coated glass came to market in the same period.
Window sizes changed, however, with the energy crises of the 1970s with a significant impact on window design. Windows became smaller, and focus shifted to energy optimization - a focus that has been maintained until today, where energy, climate and environment is paramount, and sustainability is a prime motivator for the choice of materials. New technologies; with low energy double and triple panes have allowed bigger windows - wall to wall - floor to ceiling - bigger skylight installations. Buildings can be covered completely in glass - but glass alone is not creating a comfortable and daylit building.
Today's windows must be seen together with accessories that ensure solar shading and glare control. Daylight and ventilation by windows are inseparably connected to indoor climate; encompassing temperature, humidity, lighting, air quality, ventilation and noise levels in the building.
Daylight in Architecture
“The history of architecture is the history of the struggle for light” - Le Corbusier
Daylight and architecture are inherently connected. For centuries, daylight was the only efficient light available as a primary source of light in buildings and the architecture of the day was dominated by the aspiration to span wide spaces and creating openings large enough to distribute daylight to building interiors.
Human observation of the sun and the cultivation of sun-related myths go as far back as the Bronze Age, illustrated with Stonehenge, whose tone gateways are positioned to allow the rays of the sun at certain elevations to fall at precisely defined points in the center of the circle. While civilization on the European continent lagged well behind in the deepest Stone Age, The Egyptians worshipped Ra, the Sun God, who embodied the sun itself. Findings indicate that the pyramids were turned into geometrically precisely calculated mirrors – with the top capstone made of metal – and designed to catch the first and the last rays of daylight, and appeared as a light-filled torch beaming out over the earth.
The Greek's use of sundials made them aware of solar geometry and how it could be related to building design; “in houses that look toward the south, the sun penetrates the portico (patio) in winter, while in summer the path of the sun is right over our heads and above the roof so that there is shade” - as Socrates described the concept. The first step in solar design were stablished..
Vitruvius, the pre-eminent Roman architect of the first century BC, emphasized the importance of a relationship between the design of a dwelling and the sun´s path. Even the orientation of specific rooms was outlined in his “Ten Books on Architecture” - the first book on architectural theory; It recommended that winter dining rooms and baths looked towards the winter sunset “because the setting sun, facing them in all its splendor but with abated heat, lends a gender warmth to the quarter in the evening”.
The use of glass enabled openings to be larger without letting the warm interior air escape. This, together with the structural innovations of the Romans allowed large amounts of daylight into their buildings - an increasing asset as the Roman Empire reached northwards.
The Pantheon in Rome demonstrates a subtle and skillful us of daylight; as the sun moves, the sunpatch traces a path across the interior, producing strong shadows as well as scattering light diffusely into the vast interior to reveal all its full architectural plasticity.
The symbolism and imagery of light and dark were ideal vehicles for the expression of religious mysteries continued in Gothic architecture and the structural sophistication allowed to build great, highly glazed with expanses of stained glass. Originating in 12th century France and lasting into the 16th century, Gothic architecture is most familiar as the architecture of many of the great cathedrals, abbeys and churches of Europe. It is also the architecture of many castles, palaces, town halls, guild halls, universities and to a less prominent extent, private dwellings, such as dorms and rooms.
Renaissance architects rejected the intricacy and verticality of the Gothic style for the simplicity and balanced proportions of classicism. Rounded arches, domes, and the classical orders were revived and proportion was the most important factor of beauty; Renaissance architects found a harmony between human proportions and buildings - resulting in clear, easily comprehended space and mass - and the perception of light changed from the religious to the representative and aesthetic; the function of daylight was now mainly one of illumination. For the first time, windows permitted transparency from both the inside and the outside of the building. Light from above was welcomed as a new symbol of quality and architects such as Bramante and Michelangelo began, for the first time, to consider skylights.
In the following Baroque period (1560-1760) the pendulum denoting the perception of light swung back towards the sentimentality. A more intense relationship with light as in evidence; the way we experienced the sum was perceived in a more sensual perspective. Baroque architecture linked light with the concepts of reason, liberty and power; the splendid mirrored walls in Ludwig XIVs´ Versailles multiplied the efficient use of light and allowed the painted barrel vaults to be admired in all its splendor.
During the Enlightenment, a fundamental shift took place in our metaphysical attitude to light - making way for a new rational way of thinking; light was transformed from a medium to into an instrument. The use of lighting began to assume a slightly less spiritual aspect.
The dawn of industrialization and onwards, light served the purpose of illuminating buildings as profane as greenhouses and factory halls. An `appetite for light´ was manifested in such projects as Crystal Palace, erected for the World exhibition building in London 1851. The light filled rooms with glazing facades were accepted initially only in public used rooms. Housing construction still favored living areas dominated by dark with a strict separation of the outside from the inside.
During early Modernism, The Larkin Building built in 1904-1906 by Frank Lloyd Wright was noted for many innovations. It was the first known office space to have air conditioning and a daylight-filled, four-story atrium formed an inspiring scene for workers. Daylight was the primary source of illumination during office hours. Unfortunately, this `historical daylighting marker´ was demolished in 1950 to give space to parking.
New industrial processes and serial manufacture opened the scope of young architects to develop new forms for contemporary architecture. “Sun, light air and space” was the order; le Corbusier advocated for the detachment of the facade from the supporting construction, which permitted free positioning of openings in the facade. Horizontal windows were introduced, and with them the possibility to impart complete, even illumination of rooms. Louis Kahns' issue, in another direction, was the emphasis of mass through structure and his work sought to create the mystique of a space and bring it into life by using the energy of natural light.
Technical progress during the Modernist to the late Modernist age opened up the possibility of implementing almost any architectural design concept. However, these options are not without their problems in terms of energy and climate technology.
Read more: D/A Magazine #4, Pablo Buonocore
“Architecture is the masterly, correct and magnificent play of masses brought together in light,” - Le Corbusier
For centuries, daylight has been the primary source of light in buildings and a vital part of architecture. We know and sense, intuitively, when we are in a building or a room where natural light touches our senses and influences our mood and wellbeing.
Historically, we will find buildings with unique solutions for lighting; like The Larkin Building, designed to maximize natural light exposure in order to create a comfortable and productive workspace. With the massive increase of artificial light usage during the 1950's, the workplaces, schools and other buildings changed dramatically with very little concern about access to - and importance of natural light.
Over the past two decades, however, daylighting has regained its position in architecture. Today we acknowledge that our bodies need daylight as a nutrient for our metabolic processes and we know that daylight improves vision, overall psychological health, and has a positive effect on peoples’ performance, attentiveness, satisfaction and capacity to learn.
Yet, today we tend to spend up to 90% of our time indoors, where we are exposed to relatively low light levels and where the patterns of light and darkness occur at irregular intervals. Therefore, adequate levels of daylight during the day and darkness at night are critical in maintaining key aspects of our overall health.
Preliminary evidence even suggests that low light exposure is associated with diminished health and well-being and can lead to reduced sleep quality, low mood and a lack of energy.
Daylight is not only crucial to human health but it is also a sustainable source of energy, as the considerate use of daylighting in buildings can reduce dependency on electrical lighting. Intelligent systems that link daylight with electric light have been available for many years, but their success requires that professionals have detailed knowledge of both daylight and electric light.
Find an overview over relevant literature here