A tiffany lamp is a type of lamp with many different types of glass shade. The most famous was the stained leaded glass lamp. Tiffany lamps are considered part of the Art Nouveau movement.
The first Tiffany lamp was created around 1895. Beautiful in design and intricacy, each lamp was handmade by skilled craftsman, not mass or machine produced. Its designer was not, as had been thought for over 100 years, Louis Comfort Tiffany, but an unrecognized single woman named Clara Driscoll who was identified in 2007 by Rutgers professor Martin Eidelberg as being the master designer behind the most creative and valuable leaded glass lamps produced by Tiffany Studios.
Tiffany's first business venture was an interior design firm in New York, for which he designed stained glass windows.
Most of his lamps can be grouped into one of seven specific categories: Irregular Upper and Lower Border, Favrile, Geometric,Transition to Flowers, Flowered Cone, and Flowered Globe lamps. The Irregular Upper and Lower Border lamps carry an openwork crown edge that helps to stimulate a branch, tree, or shrubbery. The Favrile category, which means handcrafted, identifies the first lamps Tiffany made with this label. His initials LCT, later replaced the Favrile stamp. The Geometric category, done primarily by the male craftsman, speaks for itself. The Tiffany craftsman used geometric shapes such as triangles, squares, rectangles, and ovals to form these patterns for these lamps. Next is the Transition to Flowers group, which is subdivided into the Flowered Cone and Globe lamps. All of these lamps follow a nature, or botanical, design using flowers, dragonflies, spiders with webs, butterflies, and peacock feathers. The difference within these two smaller categories is the difference in the lamp shapes, basically a cone and a globe.
Aside from their categorization every lamp is prepared by using the Copper Foil method. First a pattern for the lamp is drawn out on a heavy piece of cardboard. Next a number and glass color is written on the pattern piece. After the pattern is drawn and labeled, the glass is laid over it and traced. Once the pattern is traced onto the glass, the pieces can be cut and ground to their correct shape. Next the pieces need to be cleaned so the copper foil can be applied to the edges. The copper foil solution allows the pieces to adhere together. After the lamp has been placed accordingly and it is fully bonded, the edges need to be soldered together for a firm hold. Finally after the lamp has been soldered it is cleaned to bring out its beauty.
Louis Comfort Tiffany
Born February 18, 1848(1848-02-18)
Louis Comfort Tiffany (February 18, 1848 – January 17, 1933) was an American artist and designer who worked in the decorative arts and is best known for his work in stained glass. He is the American artist most associated with the Art Nouveau and Aesthetic movements. Tiffany was affiliated with a prestigious collaborative of designers known as the Associated Artists, which included Lockwood de Forest, Candace Wheeler, and Samuel Colman. Tiffany designed stained glass windows and lamps, glass mosaics, blown glass, ceramics, jewelry, enamels and metalwork.
Louis was the son of Charles Lewis Tiffany, founder of Tiffany and Company; and Harriet Olivia Avery Young. Louis married Mary Woodbridge Goddard (c1850-1884) on May 15, 1872 in Norwich, Connecticut and had the following children: Mary Woodbridge Tiffany (1873-1963) who married Graham Lusk; Charles Louis Tiffany I (1874-1874); Charles Louis Tiffany II (1878-1947); and Hilda Goddard Tiffany (1879-1908), the youngest. After the death of his wife, he married Louise Wakeman Knox (1851-1904) on November 9, 1886. They had the following children: Louise Comfort Tiffany (1887-1974); Julia DeForest Tiffany (1887-1973) who married Gurdon S. Parker then married Francis Minot Weld; Annie Olivia Tiffany (1888-1892); and Dorothy Trimble Tiffany (1891-1979), who, as Dorothy Burlingham, later became a noted psychoanalyst and lifelong friend and partner of Anna Freud. Many of Tiffany's descendants are active in the arts, politics, and the sciences. Only one descendant is working in glass today — Dr. Rodman Gilder Miller of Seattle, Washington.
He attended school at Pennsylvania Military Academy in Chester, Pennsylvania, and Eagleswood Military Academy in Perth Amboy, New Jersey. His first artistic training was as a painter, studying under George Inness and Samuel Colman in New York City and Léon Bailly in Paris.
Louis Comfort Tiffany started out as a painter. He became interested in glassmaking from about 1875 and worked at several glasshouses in Brooklyn between then and 1878. In 1879, he joined with Candace Wheeler, Samuel Colman and Lockwood de Forest to formLouis Comfort Tiffany and Associated American Artists. Tiffany's leadership and talent, as well as by his father's money and connections, led this business to thrive.Their most notable design in 1881 was the opalescent floor to ceiling glass screen commissioned for the White House by President Chester A. Arthur. The interior design of the Mark Twain House in Hartford CT. was also done in 1881 and still remains.
A desire to concentrate on art in glass led to the breakup of the firm in 1885, when Tiffany chose to establish his own glassmaking firm later that same year. The first Tiffany Glass Company was incorporated on December 1, 1885, which in 1902 became known as theTiffany Studios.
The Holy City (1905) – St. John's vision on the isle of Patmos. Having 58 panels, this window is said to be one of the largest made by the Tiffany Studios. It is located at Brown Memorial Presbyterian Church (Baltimore, Maryland), which has eleven Tiffany windows.
In the beginning of his career, Tiffany used cheap jelly jars and bottles because they had the mineral impurities that finer glass lacked. When he was unable to convince fine glassmakers to leave the impurities in, he began making his own glass. Tiffany used opalescent glass in a variety of colors and textures to create a unique style of stained glass. This can be contrasted with the method of painting in glass paint or enamels on colorless glass that had been the dominant method of creating stained glass for several hundred years in Europe. (The First Presbyterian Church building of 1905 in Pittsburgh, Pennsylvania is unique in that it uses Tiffany windows that partially make use of painted glass.) Use of the colored glass itself to create stained glass pictures was motivated by the ideals of the Arts and Crafts movement and its leader William Morris in England. Fellow artist and glassmakers Oliver Kimberly and Frank Duffner, founders of the Duffner and Kimberly company, and John La Farge were Tiffany's chief competitors in this new American style of stained glass. Tiffany, Duffner and Kimberly, along with La Farge, had learned their craft at the same glasshouses in Brooklyn in the late-1870s.
In 1893, Tiffany built a new factory called the Stourbridge Glass Company, later called Tiffany Glass Furnaces, which was located in Corona, Queens, New York. In 1893, his company also introduced the term, Favrile in conjunction with his first production of blown glass at his new glass factory. Some early examples of his lamps were exhibited in the 1893 World's Fair in Chicago.At the Exposition Universelle (1900),Paris 1900,he won a gold medal with his stained glass windows The Four Seasons
He trademarked Favrile (from the old French word for handmade) on November 13, 1894. He later used this word to apply to all of his glass, enamel and pottery. Tiffany's first commercially produced lamps date from around 1895. Much of his company's production was in making stained glass windows and Tiffany lamps, but his company designed a complete range of interior decorations. At its peak, his factory employed more than 300 artisans. Recent scholarship led by Rutgers professor Martin Eidelberg suggests that a team of talented single women designers led by Clara Driscoll played a big role in designing many of the floral patterns on the famous Tiffany lamp as well as for other creations.
Tiffany used all his skills in the design of his own house, the 84-room Laurelton Hall, in the village of Laurel Hollow, on Long Island, New York completed in 1905. Later this estate was donated to his foundation for art students along with 60 acres (243,000 m²) of land, sold in 1949, and was destroyed by a fire in 1957.
The Charles Hosmer Morse Museum of American Art in Winter Park, Florida houses the world's most comprehensive collection of the works of Louis Comfort Tiffany (in Europe it is in Accrington,England) including Tiffany jewelry, pottery, paintings, art glass, leaded-glass windows, lamps, and the chapel interior he designed for the 1893 World's Columbian Exposition in Chicago. After the close of the exposition, a generous benefactor purchased the entire chapel for installation in the crypt of the Cathedral of Saint John the Divine, New York in New York City. As construction on the cathedral continued, the chapel fell into disuse, and in 1916, Tiffany removed the bulk of it to Laurelton Hall. After the 1957 fire, the chapel was rescued by Hugh McKean, a former art student in 1930 at Laurelton Hall, and his wife Jeannette Genius McKean, and now occupies an entire wing of the Morse Museum which they founded. Many glass panels from Laurelton Hall are also there; for many years some were on display in local restaurants and businesses in Central Florida. Some were replaced by full-scale color transparencies after the museum opened. A major exhibit at New York's Metropolitan Museum of Art on Laurelton Hall opened in November 2006. A new exhibit at the New-York Historical Society through 28 May 2007 features new information about the women who worked for Tiffany and their contribution to designs credited to Tiffany. In addition, since 1995 the Queens Museum of Art has featured a permanent collection of Tiffany objects, which continues Tiffany’s presence in Corona, Queens where the company's studios were once located.
The only Tiffany windows outside of the USA are situated at the American Church in Paris on the Quai d'Orsay. They are classified as National Monuments by the French government and were commissioned by Rodman Wanamaker in 1901 for the original American Church building on the right bank of the Seine.
Louis Comfort Tiffany died on January 17, 1933, and is buried in Green-Wood Cemetery in Brooklyn, New York.
Examples of Tiffany's work
Tiffany glass is the generic name used here to describe the many and varied types of glass developed and produced from 1878 to 1933 at the Tiffany Studios, by Louis Comfort Tiffany. However, it is his head designer until 1909, Clara Driscoll, who is the person now recognized as the real creator of the finest of the leaded glass Tiffany Lamps. They are now both remembered as the most famous stained glass artists of the United States and possibly the world at that time.
In 1865, Tiffany traveled to Europe and in London he visited the Victoria and Albert Museum, whose extensive collection of Roman and Syrian glass made a deep impression on him. He admired the coloration of medieval glass and was convinced that the quality of contemporary glass could be improved upon.
In his own words, the "Rich tones are due in part to the use of pot metal full of impurities, and in part to the uneven thickness of the glass, but still more because the glass maker of that day abstained from the use of paint".
Tiffany was an interior designer, and in 1878 his interest turned towards the creation of stained glass, when he opened his own studio and glass foundry because he was unable to find the types of glass that he desired in interior decoration. His inventiveness both as a designer of windows and as a producer of the material with which to create them was to become renowned.
Tiffany wanted the glass itself to transmit texture and rich colors and he developed a type of glass he called Favrile. Some of the most significant products of Tiffany's glass manufacture are described here.
Girl with Cherry Blossoms illustrates many types of glass employed by Tiffany including elaborate polychrome painting of the face, drapery glass for the dress, opalescent glass for the blossoms, streaky glass in the border, fracture-streamer glass in the background and what may be iridescent glass in the beads.
Types of Tiffany glass
The term opalescent glass is commonly used to describe glass where more than one color is present, being fused during the manufacture, as against flashed glass in which two colors may be laminated, or silver stained glass where a solution of silver nitrate is superficially applied, turning red glass to orange and blue glass to green. Some opalescent glass was used by several stained glass studios in England from the 1860s and 1870s onwards, notably Heaton, Butler and Bayne. Its use became increasingly common. Opalescent glass is the basis for the range of glasses created by Tiffany.
Tiffany patented Favrile glass in 1880. The trade name Favrile was derived from the French word, fabrile, meaning handcrafted.
Favrile glass often has a distinctive characteristic that is common in some glass from Classical antiquity: it possesses a superficial iridescence. This iridescence causes the surface to shimmer, but also causes a degree of opacity. This iridescent effect of the glass was obtained by mixing different colors of glass together while hot.
According to Tiffany:
"Favrile glass is distinguished by brilliant or deeply toned colors, usually iridescent like the wings of certain American butterflies, the necks of pigeons and peacocks, the wing covers of various beetles."
Streamer glass refers to a sheet of glass with a pattern of glass strings affixed to its surface. Tiffany made use of such textured glass to represent, for example, twigs, branches and grass.
Streamers are prepared from very hot molten glass, gathered at the end of a punty (pontil) that is rapidly swung back and forth and stretched into long, thin strings that rapidly cool and harden. These hand-stretched streamers are pressed on the molten surface of sheet glass during the rolling process, and become permanently fused.
Fracture glass refers to a sheet of glass with a pattern of irregularly shaped, thin glass wafers affixed to its surface. Tiffany made use of such textured glass to represent, for example, foliage seen from a distance.
The irregular glass wafers, called fractures, are prepared from very hot, colored molten glass, gathered at the end of a blowpipe. A large bubble is forcefully blown until the walls of the bubble rapidly stretch, cool and harden. The resulting glass bubble has paper-thin walls and is immediately shattered into shards. These hand blown shards are pressed on the surface of the molten glass sheet during the rolling process, to which they become permanently fused.
Fracture-streamer glass refers to a sheet of glass with a pattern of glass strings, and irregularly shaped, thin glass wafers, affixed to its surface. Tiffany made use of such textured glass to represent, for example, twigs, branches and grass, and distant foliage.
The process is as above except that both streamers and fractures are applied to sheet glass during the rolling process.
Ripple glass refers to a sheet of textured glass with marked surface waves. Tiffany made use of such textured glass to represent, for example, water or leaf veins.
The texture is created during the glass sheet-forming process. A sheet is formed from molten glass with a roller that spins on itself, while travelling forward. Normally the roller spins at the same speed as its own forward motion, and the resulting sheet has a smooth surface. In the manufacture of rippled glass, the roller spins faster than its own forward motion. The rippled effect is retained as the glass cools.
Herringbone ripple glass
Ring mottle glass
Ring mottle glass refers to sheet glass with a pronounced mottle created by localized, heat-treated opacification and crystal-growth dynamics. Ring mottle glass was invented by Tiffany in the early 20th century. Tiffany's distinctive style exploited glass containing a variety of motifs such as those found in ring mottle glass, and he relied minimally on painted details.
When Tiffany Studio closed in 1928, the secret formula for making ring mottle glass was forgotten and lost. Ring mottle glass was re-dicscovered in the late sixties by Eric Lovell of Uroboros Glass. Traditionally used for organic details on leaves and other natural elements, ring mottles also find a place in contemporary work when abstract patterns are desired.
Ring mottle glass
Drapery glass refers to a sheet of heavily folded glass that suggests fabric folds. Tiffany made adundant use of drapery glass in ecclesiastical stained glass windows to add a 3-dimensional effect to flowing robes and angel wings, and to imitate the natural coarseness of magnolia petals.
The making of drapery glass requires skill and experience. A small diameter hand-held roller is manipulated forcefully over a sheet of molten glass to produce heavy ripples, while folding and creasing the entire sheet. The ripples become rigid and permanent as the glass cools. Each sheet produced from this artisanal process is unique.
Drapery glass incorporated in a reproduction of Tiffany's "Magnolia" lampshade
Techniques for cutting Tiffany glass
In order to cut streamer, fracture or ripple glass, the sheet may be scored on the side without streamers, fractures or ripples with a carbide glass cutter, and broken at the score line with breaker-grozier pliers.
In order to cut drapery glass, the sheet may be placed on styrofoam, scored with a carbide glass cutter, and broken at the score line with breaker-grozier pliers, but a bandsaw or ringsaw are the preferred tools.
Lighting or illumination is the deliberate application of light to achieve some aesthetic or practical effect. Lighting includes use of both artificial light sources such as lamps and natural illumination of interiors from daylight. Daylighting (through windows, skylights, etc.) is often used as the main source of light during daytime in buildings given its low cost. Artificial lighting represents a major component of energy consumption, accounting for a significant part of all energy consumed worldwide. Artificial lighting is most commonly provided today by electric lights, but gas lighting, candles, or oil lamps were used in the past, and still are used in certain situations. Proper lighting can enhance task performance or aesthetics, while there can be energy wastage and adverse health effects of poorly designed lighting. Indoor lighting is a form of fixture or furnishing, and a key part of interior design. Lighting can also be an intrinsic component of landscaping.
Low-intensity lighting and haze in a concert hall allows laser effects to be visible
Daylight utilized at the train station Gare de l'Est Paris
Lighting fixtures come in a wide variety of styles for various functions. The most important functions are as a holder for the light source, to provide directed light and to avoid visual glare. Some are very plain and functional, while some are pieces of art in themselves. Nearly any material can be used, so long as it can tolerate the excess heat and is in keeping with safety codes.
An important property of light fixtures is the luminous efficacy or wall-plug efficiency, meaning the amount of usable light emanating from the fixture per used energy, usually measured in lumen per watt. A fixture using replaceable light sources can also have it's efficiency quoted as the percentage of light passed from the "bulb" to the surroundings. The more transparent the lighting fixture is, the higher efficacy. Shading the light will normally decrease efficacy but increase the directionality and the visual comfort probability.
A demonstration of the effects of different kinds of lighting
Lighting is classified by intended use as general, localized, or task lighting, depending largely on the distribution of the light produced by the fixture.
Wall-mounted light with shadows
Forms of Lighting include alcove lighting, which like most other uplighting is indirect. This is often done with fluorescent lighting or rope light, or occasionally with neon lighting. It is a form of backlighting.
Soffit or close to wall lighting can be general or a decorative wall-wash, sometimes used to bring out texture (like stucco or plaster) on a wall, though this may also show its defects as well. The effect depends heavily on the exact type of lighting source used.
Recessed lighting (often called "pot lights" in Canada, "can lights" or 'high hats" in the U.S.) is popular, with fixtures mounted into the ceiling structure so as to appear flush with it. These downlights can use narrow beam spotlights, or wider-angle floodlights, both of which are bulbs having their own reflectors. There are also downlights with internal reflectors designed to accept common 'A' lamps (light bulbs) which are generally less costly than reflector lamps. Downlights can be incandescent, fluorescent, HID (high intensity discharge) or LED, though only reflector incandescent or HID lamps are available in spot configuration.
Track lighting, invented by Lightolier, was popular at one point because it was much easier to install than recessed lighting, and individual fixtures are decorative and can be easily aimed at a wall. It has regained some popularity recently in low-voltage tracks, which often look nothing like their predecessors because they do not have the safety issues that line-voltage systems have, and are therefore less bulky and more ornamental in themselves. A master transformer feeds all of the fixtures on the track or rod with 12 or 24 volts, instead of each light fixture having its own line-to-low voltage transformer. There are traditional spots and floods, as well as other small hanging fixtures. A modified version of this is cable lighting, where lights are hung from or clipped to bare metal cables under tension.
A sconce is a wall-mounted fixture, particularly one that shines up and sometimes down as well. A torchiere is an uplight intended for ambient lighting. It is typically a floor lamp but may be wall-mounted like a sconce.
The portable or table lamp is probably the most common fixture, found in many homes and offices. The standard lamp and shade that sits on a table is general lighting, while the desk lamp is considered task lighting. Magnifier lamps are also task lighting.
Animated fountain in Moscow's Square of Europe, lit at night.
The illuminated ceiling was once popular in the 1960s and 1970s but fell out of favor after the 1980s. This uses diffuser panels hung like a suspended ceiling below fluorescent lights, and is considered general lighting. Other forms include neon, which is not usually intended to illuminate anything else, but to actually be an artwork in itself. This would probably fall under accent lighting, though in a dark nightclub it could be considered general lighting. Underwater accent lighting is also used for koi ponds, fountains, swimming pools and the like.
In a movie theater each step in the aisles is usually marked with a row of small lights, for convenience and safety when the film has started, hence the other lights are off. Traditionally made up of small low wattage, low voltage lamps in a track or translucent tube, these are rapidly being replaced with LED based versions.
Vehicles typically include headlamps and tail lights. Headlamps are white or selective yellow lights placed in the front of the vehicle, designed to illuminate the upcoming road and to make the vehicle more visible. Tail and brake lights are red and emit light to the rear so as to reveal the vehicle's direction of travel to following drivers. White rear-facing reversing lamps indicate that the vehicle's transmission has been placed in the reverse gear, warning anyone behind the vehicle that it is moving backwards, or about to do so. Flashing turn signals on the front, side, and rear of the vehicle indicate an intended change of position or direction.
In addition to lighting for useful purposes, manufacturers would sometimes backlight their logos and or other translucent paneling in the 1970s. In the 1990s, a popular trend was to customize vehicles with neon lighting, especially underneath the body of a car. In the 2000s, neon lighting is increasingly yielding to digital vehicle lighting, in which bright LEDs are placed on the car and operated by a computer which can be customized and programmed to display a range of changing patterns and colors, a technology borrowed from Christmas lights.
Commonly called 'light bulbs', lamps are the removable and replaceable portion of a luminaire which converts electrical energy to both visible and non-visible electromagnetic energy. Specialists who work with lighting, carefully avoid energetic units for measuring of the light output of sources of light due to the spectral response of human visual perception. For example, instead of watt per steradian, the special unit candela is used; 1 candela=(1/683) W/steradian for monochromatic light at 555 nm wavelength. Common characteristics used to evaluate lamp quality include efficacy measured in lumens per watt, typical lamp life measured in hours, and Color Rendering Index on a scale of 0 to 100. Cost of replacement lamps is also an important factor in any design.
Design and architecture
Lighting without windows: The Pantheon in the 18th century, painted by Giovanni Paolo Panini.
Lighting design as it applies to the built environment, also known as 'architectural lighting design', is both a science and an art. Comprehensive lighting design requires consideration of the amount of functional light provided, the energy consumed, as well as the aesthetic impact supplied by the lighting system. Some buildings, like surgical centers and sports facilities, are primarily concerned with providing the appropriate amount of light for the associated task. Some buildings, like warehouses and office buildings, are primarily concerned with saving money through the energy efficiency of the lighting system. Other buildings, like casinos and theatres, are primarily concerned with enhancing the appearance and emotional impact of architecture through lighting systems. Therefore, it is important that the sciences of light production and luminaire photometrics are balanced with the artistic application of light as a medium in our built environment. These electrical lighting systems should also consider the impacts of, and ideally be integrated with, daylighting systems. Factors involved in lighting design are essentially the same as those discussed above in energy conservation analysis. The provision of excess amounts of light is known as over-illumination.
Mathematical modeling is normally used for complex lighting design, whereas, for simple configurations, calculations can be carried out by hand, potentially with reference tables. Based on the positions and mounting heights of the fixtures, and their photometric characteristics, the proposed lighting layout can be checked for uniformity and quantity of illumination. For larger projects or those with irregular floor plans, lighting design software can be used. Each fixture has its location entered, and the reflectance of walls, ceiling, and floors can be entered. The computer program will then produce a set of contour charts overlaid on the project floor plan, showing the light level to be expected at the working height. More advanced programs can include the effect of light from windows or skylights, allowing further optimization of the operating cost of the lighting installation.
The Zonal Cavity Method is used as a basis for both hand, tabulated, and computer calculations. This method uses the reflectance coefficients of room surfaces to model the contribution to useful illumination at the working level of the room due to light reflected from the walls and the ceiling. Simplified photometric values are usually given by fixture manufacturers for use in this method.
Computer modelling of outdoor flood lighting usually proceeds directly from photometric data. The total lighting power of a lamp is divided into small solid angular regions. Each region is extended to the surface which is to be lit and the area calculated, giving the light power per unit of area. Where multiple lamps are used to illuminate the same area, each one's contribution is summed. Again the tabulated light levels (in lux or foot-candles) can be presented as contour lines of constant lighting value, overlaid on the project plan drawing. Hand calculations might only be required at a few points, but computer calculations allow a better estimate of the uniformity and lighting level.
Practical lighting design must take into account the gradual decrease in light levels from each lamp owing to lamp aging, lamp burnout, and dirt accumulation on fixture and lamp surfaces. Empirically-established depreciation factors are listed in lighting design handbooks.
Notable lighting designers
Luminance is a photometric measure of the density of luminous intensity in a given direction. It describes the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle. The SI unit for luminance is candela per square metre (cd/m2). The CGS unit of luminance is the stilb, which is equal to one candela per square centimetre or 10 kcd/m2.
Light quality is often measured in units of the Color Rendering Index or CRI. This is a measure on how well the light source imitates the light of a blackbody radiator at the same correlated color temperature, when the light is reflected of a set of standard color samples. The index is normalized so a perfect blackbody has the index Ra=100 and deviations from this causes the index to decrease. It has been argued that the CRI has little correlation with what people consider "good" lighting, and different replacements metrics has been proposed.(Guo & Houser 2004)
Artificial lighting consumes a significant part of all electrical energy consumed worldwide. In homes and offices from 20 to 50 percent of total energy consumed is due to lighting. Most importantly, for some buildings over 90 percent of lighting energy consumed can be an unnecessary expense through over-illumination. The cost of that lighting can be substantial. A single 100 W light bulb used just 6 hours a day can cost over $25 per year to use (.12/kWh). Thus lighting represents a critical component of energy use today, especially in large office buildings where there are many alternatives for energy utilization in lighting. There are several strategies available to minimize energy requirements in any building:
It is valuable to provide the correct light intensity and color spectrum for each task or environment. Otherwise, energy not only could be wasted but over-illumination can lead to adverse health and psychological effects.
Specification of illumination requirements is the basic concept of deciding how much illumination is required for a given task. Clearly, much less light is required to illuminate a hallway or bathroom compared to that needed for a word processing work station. Prior to 1970 (and too often even today), a lighting engineer would simply apply the same level of illumination design to all parts of the building without considering usage. Generally speaking, the energy expended is proportional to the design illumination level. For example, a lighting level of 80 footcandles might be chosen for a work environment involving meeting rooms and conferences, whereas a level of 40 footcandles could be selected for building hallways. If the hallway standard simply emulates the conference room needs, then twice the amount of energy will be consumed as is needed for hallways. Unfortunately, most of the lighting standards even today have been specified by industrial groups who manufacture and sell lighting, so that a historical commercial bias exists in designing most building lighting, especially for office and industrial settings. Beyond the energy factors being considered, it is important not to over-design illumination, lest adverse health effects such as headache frequency, stress, and increased blood pressure be induced by the higher lighting levels. In addition, glare or excess light can decrease worker efficiency.
Analysis of lighting quality particularly emphasizes use of natural lighting, but also considers spectral content if artificial light is to be used. Not only will greater reliance on natural light reduce energy consumption, but will favorably impact human health and performance. For example, it is clear that student test scores are improved for children who learn in the presence of greater natural light. Artificial night-lighting has been associated with irregular menstrual cycles.
Kerosene and whale-oil lamps
In 1849, Dr. Abraham Gesner, a Canadian geologist, devised a method where kerosene could be distilled from petroleum. Earlier coal-gas methods had been used for lighting since the 1820s, but they were expensive. Gesner's kerosene was cheap, easy to produce, could be burned in existing lamps, and did not produce an offensive odor as did most whale oil. It could be stored indefinitely, unlike whale oil, which would eventually spoil. The American petroleum boom began in the 1850s. By the end of the decade there were 30 kerosene plants operating in the United States. The cheaper, more efficient fuel began to drive whale oil out of the market. John D. Rockefeller was most responsible for the commercial success of kerosene. He set up a network of kerosene distilleries which would later become Standard Oil, thus completely abolishing the need for whale-oil lamps.
Compact fluorescent lamps
Compact fluorescent lamps (aka 'CFLs') use less power to supply the same amount of light as an incandescent lamp. Due to the ability to reduce electric consumption, many organizations have undertaken measures to encourage the adoption of CFLs. Some electric utilities and local governments have subsidized CFLs or provided them free to customers as a means of reducing electric demand. For a given light output, CFLs use between one fifth and one quarter of the power of an equivalent incandescent lamp. One of the simplest and quickest ways for a household or business to become more energy efficient is to adopt CFLs as the main lamp source, as suggested by the Alliance for Climate Protection
LED lamps have been advocated as the newest and best environmental lighting method. According to the Energy Saving Trust, LED lamps use only 10% power compared to a standard incandescent bulb, where compact fluorescent lamps use 20% and energy saving halogen lamps 70%. A downside is still the initial cost, which is higher than that of compact fluorescent lamps. However, when the life expectancy and other factors are incorporated, regular LED's are not more costly than CFL lamps. General Electric expects to begin producing organic LED's for architectural use by 2010.
From a military standpoint, lighting is a critical part of the battlefield conditions. Shadows are good places to hide, while bright areas are more exposed. It is often beneficial to fight with the Sun or other light source behind you, giving your enemy disturbing visual glare and partially hiding your own movements in backlight. If natural light is not present searchlights and flares can be used. However the use of light may disclose your own hidden position and modern warfare have seen increased use of night vision through the use of infrared cameras and image intensifiers.
Flares can also be used by the military to mark positions, usually for targeting, but laser-guided and GPS weapons have eliminated this need for the most part.
The International Commission on Illumination (CIE) is an international authority and standard defining organization on color and lighting. Publishing widely used standard metrics such as various CIE color spaces and the color rendering index.
The Illuminating Engineering Society of North America (IESNA), in conjunction with organizations like ANSI and ASHRAE, publishes guidelines, standards, and handbooks that allow categorization of the illumination needs of different built environments. Manufacturers of lighting equipment publish photometric data for their products, which defines the distribution of light released by a specific luminaire. This data is typically expressed in standardized form defined by the IESNA.
The International Association of Lighting Designers (IALD) is an organization which focuses on the advancement of lighting design education and the recognition of independent professional lighting designers. Those fully independent designers who meet the requirements for professional membership in the association typically append the abbreviation IALD to their name.
The Professional Lighting Designers Association (PLDA), formerly known as ELDA is an organisation focusing on the promotion of the profession of Architectural Lighting Design. They publish a monthly newsletter and organise different events throughout the world.
The National Council on Qualifications for the Lighting Professions (NCQLP) offers the Lighting Certification Examination which tests rudimentary lighting design principles. Individuals who pass this exam become ‘Lighting Certified’ and may append the abbreviation LC to their name. This certification process is one of three national (U.S.) examinations (the others are CLEP and CLMC) in the lighting industry and is open not only to designers, but to lighting equipment manufacturers, electric utility employees, etc. Generally speaking there is no legal or practical requirement for the lighting design team to possess the certifications discussed.
The Professional Lighting And Sound Association (PLASA) is a UK-based trade organisation representing the 500+ individual and corporate members drawn from the technical services sector. Its members include manufacturers and distributors of stage and entertainment lighting, sound, rigging and similar products and services, and affiliated professionals in the area. They lobby for and represent the interests of the industry at various levels, interacting with government and regulating bodies and presenting the case for the entertainment industry. Example subjects of this representation include the ongoing review of radio frequencies (which may or may not affect the radio bands in which wireless microphones and other devices use) and engaging with the issues surrounding the introduction of the RoHS (Restriction of Hazardous Substances Directive) regulations.
A light fixture is an electrical device used to create artificial light or illumination. A luminaire is a lighting fixture complete with the light source or lamp, the reflector for directing the light, an aperture (with or without a lens), the outer shell or housing for lamp alignment and protection, an electrical ballast, if required, and connection to a power source A wide variety of special light fixtures are created for use in the automotive industry, aerospace, marine and medicine.
Light fixtures are classified by how the fixture is installed, the light function or lamp type.
Light fixture is US usage, in English it is called a light fitting, however Luminaire is the international IEC terminology for technical use.
A wide array of light fixtures
Free-standing or portable
Tiffany dragonfly desk lamp with pigeon sculptures
A chandelier light fixture
A garden solar lamp is an example of landscape lighting
Special purpose lights
Betty lamp, butter lamp, carbide lamp, gas lighting, kerosene lamp, oil lamp, rush light, torch, candle, Limelight, gas mantle
Safety lamps: Davy lamp & Geordie lamp
Xenon arc lamp, Yablochkov candle
A-lamp, PAR Parabolic reflector lamp (PAR), Reflector lamp (R), Bulged reflector lamp (BR) (Refer to lamp bases)
· Obsolete types: Limelight, Carbon button lamp, Mazda (light bulb), Nernst glower
· Novelty: Lava lamp
· Special purpose: Heat lamp, Globar, gas mantle
Mercury-vapor lamp, Metal-halide (HMI, HQI, CDM), Sodium vapor or "high pressure sodium"
· Neon sign,
Linear fluorescent, Compact Fluorescent Lamp (CFL), Blacklight
Light fixture controls