fluorescent lamp

fluorescent lamp is a type of electric lighting that works on the principle of electric discharge in a gas, involving ionization of argon and mercury vapor with electrodes made of tungsten and molybdenum, as developed by General Electric and Osram. The technology is closely related to plasma lamps and neon lamps, which were invented by Georges Claude and Daniel McFarlan Moore. Fluorescent lamps are widely used in commercial lighting and industrial lighting, including applications in office buildings, warehouses, and factories, as well as in residential lighting for homes and apartments, often in conjunction with incandescent lamps and halogen lamps. The development of fluorescent lamps involved the work of many scientists and engineers, including Nikola Tesla, Thomas Edison, and Willis Whitney, who made significant contributions to the field of electrical engineering at Westinghouse Electric Corporation and Massachusetts Institute of Technology.

Introduction

Fluorescent lamps are a popular choice for lighting due to their high luminous efficacy and long lifespan, making them a cost-effective option for many applications, including street lighting and parking garage lighting, as used in cities like New York City and Tokyo. They are also widely used in display lighting for retail stores and museums, such as the Louvre and the Metropolitan Museum of Art, where they are often used in conjunction with track lighting and spotlights. The use of fluorescent lamps has been promoted by organizations such as the United States Department of Energy and the International Energy Agency, which have recognized their potential for energy conservation and greenhouse gas reduction. Fluorescent lamps have also been used in medical lighting applications, including operating rooms and examination rooms, at hospitals like Johns Hopkins Hospital and Massachusetts General Hospital.

History

The development of fluorescent lamps began in the early 20th century, with the work of Peter Cooper Hewitt and Richard Threlfall, who experimented with gas discharge lamps at Columbia University and University of Cambridge. The first practical fluorescent lamp was developed in the 1930s by a team of scientists at General Electric, including George Inman, Willis Whitney, and Richard Threlfall, who worked on the project at General Electric Research Laboratory. The first commercial fluorescent lamps were released in the 1930s and quickly gained popularity due to their high efficiency and long lifespan, leading to widespread adoption in industrial lighting and commercial lighting applications, including factories like Ford Motor Company and General Motors. The development of fluorescent lamps also involved the work of scientists like Enrico Fermi and Ernest Lawrence, who made significant contributions to the field of nuclear physics at University of Chicago and University of California, Berkeley.

Construction

Fluorescent lamps consist of a glass tube filled with a gas, typically argon or krypton, and a small amount of mercury vapor, which is excited by an electric discharge to produce ultraviolet light. The ultraviolet light is then converted to visible light by a phosphor coating on the inside of the tube, made from materials like zinc sulfide and cadmium sulfide, which are produced by companies like DuPont and 3M. The electrodes are typically made of tungsten and molybdenum, which are used in high-temperature applications like rocket propulsion and nuclear reactors, developed by NASA and Los Alamos National Laboratory. The construction of fluorescent lamps involves a number of complex processes, including glassblowing and vacuum pumping, which are used in the production of light bulbs and vacuum tubes by companies like Corning Incorporated and Vacuum Tube Corporation of America.

Types

There are several types of fluorescent lamps, including linear fluorescent lamps, compact fluorescent lamps, and circline fluorescent lamps, which are used in a variety of applications, including residential lighting and commercial lighting. Linear fluorescent lamps are the most common type and are widely used in office buildings and factories, while compact fluorescent lamps are often used in residential lighting and portable lighting applications, such as table lamps and floor lamps. Circline fluorescent lamps are used in display lighting and signage applications, such as billboards and advertising signs, which are designed by companies like Ogilvy & Mather and J. Walter Thompson. Other types of fluorescent lamps include high-intensity discharge lamps and xenon lamps, which are used in high-bay lighting and stadium lighting applications, such as Wembley Stadium and Yankee Stadium.

Operation

Fluorescent lamps operate by creating an electric discharge in the gas inside the tube, which excites the mercury vapor and produces ultraviolet light. The ultraviolet light is then converted to visible light by the phosphor coating on the inside of the tube, producing a bright, white light, similar to daylight and incandescent light. The operation of fluorescent lamps involves a number of complex processes, including ionization and recombination, which are studied by scientists like Stephen Hawking and Richard Feynman at University of Cambridge and California Institute of Technology. The efficiency of fluorescent lamps is also influenced by factors like temperature and humidity, which can affect the performance of the lamp, as studied by researchers at National Institute of Standards and Technology and Sandia National Laboratories.

Environmental_impact

Fluorescent lamps have a significant environmental impact due to the presence of mercury and other hazardous materials in the lamp, which can contaminate soil and water if not disposed of properly, as highlighted by organizations like Environmental Protection Agency and World Health Organization. The production of fluorescent lamps also requires significant amounts of energy and resources, including electricity and raw materials, which can contribute to greenhouse gas emissions and climate change, as studied by researchers at Intergovernmental Panel on Climate Change and National Oceanic and Atmospheric Administration. However, fluorescent lamps can also help reduce energy consumption and greenhouse gas emissions by providing a more efficient alternative to incandescent lamps and halogen lamps, as promoted by organizations like United States Department of Energy and European Union. Category:Lighting