Live entertainment has been an important part of human life for thousands of years. The technology to illuminate actors, musicians, and speakers has changed immensely, although the source of the light has only changed a few times through history. From sunlight to LEDs, the illumination of stages has been varied and exciting.
The early Greeks are credited with inventing theater and they used the natural sunlight as their source of illumination. They would build their performance spaces so that the afternoon sun would illuminate the stage and remain behind the audience. This was around 450 BC! Later, the Romans improved upon this concept by adding an awning over the audience to reduce glare from the large light source. For thousands of years, the sun was the primary source of entertainment lighting.
In the 1500s, theater began to move indoors and thus the need for a new source of light was required. Candles were commonly placed on large chandeliers hanging over the audience, as well as in sconces on the walls. In some cases, chandeliers would also be placed above the stage and candles were also placed on the floor (footlights) and on the sides of the stage on ladders. The dripping wax, smoke, and continual re-lighting and trimming of candles was troublesome, but tolerated.
To increase brightness and provide focused illumination, reflectors began to be used with candles in the 1600s.
The late 1780s saw the development of a new light source that became known as an oil lamp. It used a wick and vegetable or animal fat oil with the flame enclosed in cylindrical glass. For specialized theatrical effects, colored glass was used. Historians note that the Haymarket Theatre in London used levers to raise and lower tinted glass in front of the oil lamps, thus creating lighting changes on stage.
Further improvements to oil lamp technology came via the use of new lamp designs and new fuels such as kerosene. These changes provided brighter and whiter output, but were still dangerous due to the flame and fumes.
The early 1800’s brought about gas-controlled lighting. Gas was fed through pipes to burners placed on and over the stage. The output was significantly brighter than oil lamps and allowed for a new level of control. By adjusting the amount of gas to each burner, the illumination levels and areas could be adjusted. For the first time, the audience lighting could be dimmed while the stage remained illuminated.
Late in the 1830’s a new invention known as limelight became popular for entertainment illumination. A block of lime could be heated up to a point that it would become incandescent and emit a bright white light. The small and intense area of light was often placed in front of a reflector to provide control of the output. This quickly led to the ability to place lighting fixtures in the auditorium and allow uses such as front lights, followspots, and even movement effects such as fire and water.
The earliest electrical form of entertainment illumination appeared in 1846 at the Paris Opera. A carbon-arc source was used to create a beam of sunlight on stage. The carbon arc lamp creates light when two rods of carbon are electrified and touched together. As they are pulled apart an electrical arc across the gap will continue. The carbon tips heat and burn, producing a carbon vapor within the arc that is extremely luminous.
Thomas Edison is credited with creating the first incandescent bulb and, by the 1880s, it was being used in theater. Over the next 40 years, gas and limelight were completely replaced by incandescent electric light. These lamps first used carbon filaments and were later replaced with metallic filaments such as tungsten.
The mid-1960’s saw the adoption of improved incandescent lamps that used iodine or bromine (Halogen elements) within the lamp to create a chemical reaction that re-deposits evaporated tungsten back on the filament. This resulted in a much brighter output with consistent color temperature and a long life.
High-Intensity Discharge (HID)
In the 1980’s as automated lighting began to enter into the entertainment scene, the use of High Intensity Discharge (HID) lamps grew rapidly. These lamps produce light by creating an electric arc between tungsten electrodes. This arc occurs in a quartz tube that is filled with a mix of gas chemicals. When heated, the chemicals evaporate and form a plasma, which in turn increases the intensity of the light produced by the arc. Most automated luminaires still use arc-source discharge lamps due to their output, efficiency, color temperature, and cost.
Light Emitting Diode (LED)
Originally invented in the early 1960’s, LED’s have recently taken over as a primary light source in entertainment fixtures. Starting around 2008, LED-based stage luminaires could be found on stages worldwide. An LED is a semi-conductor that produces light by creating a flow of electrons within a mix of materials. The mix of materials will determine the color of the photon output. Using a blue LED to excite phosphor creates white light. LED’s are extremely energy efficient and have a long lifespan. The rich colors and high output of LEDs has led to the creation of many new types of lighting products.
Entertainment lighting sources have varied through the ages, but the main purposes of illuminating the stage and creating effects has remained the same. From early sunlight to modern LED fixtures, the path has been varied. The future will surely see further innovations and new methods of light creation.