Chicago Tribune from Chicago, Illinois • 20

1 Part 2-Pa re 8 ghtragn SaHir STrihuitf Saturday, April 18, 1959 You'll Han Wall a Light on the I -A v-; -Zli ir -ui' Za-l vf I i LAM'S i sprnsuM 1 1 i New paste! colored light bulbs male it possible to paint" with light. Four colors are available in Generat Electric's line of Coloramic bulbs: sty blue, sun gold, spring green, and dawn pink. Above: Many benefits of the new electroluminescent lighting can be obtained today thru use of conventional light sources. Shown here is a luminous wall, with flourescent lamps used behind a translucent plastic I I vV- -r j- asstewrt-iwws EACH day brought disaster. Watching from his cave dwelling, primitive man witnessed the death" of the sun every evening.

And, blanketed in darkness, his terrified mind knew no guarantee that the sun would ever return. Man's awe of light and darkness was so great that it carried into his religion. Early civilizations worshipped' the sun. For both Christians and Jews, light was the first part of the universe God created. Thru the ages, light became a universal symbol of joy and wisdom; darkness, of evil and disaster.

There also was a practical side to man's concern with light." Living in primitive times was a constant struggle against the elements, wild beasts, and starvation. Darkness made survival even more difficult. Until man broke the chains of nature, no important advances in civilization would be possible. Then some early genius discovered that fire could be controlled. Man had a portable sun a campfire or torch.

Civilization's march began in earnest, but it was a slow march. Producing light by wood burning remained the only method for eons. However, as culture developed, people moved out of caves into houses in communities. The stage was set for another major advance put some animal or vegetable oil in an open dish, drop a piece of twisted cloth, and you had a lamp. From Roman times the lamp was a principle light source in palace and peasant's hut alike.

Only trouble with the oil lamp was its foul smelling smoke, and it was cumbersome, too. A better source of light was needed. At the end of the 12th century tallow candles were introduced. Smokeless and odorless, they burned with brilliance and could be used in groups. Discovery of petroleum in 1859 led to an improved kerosene lamp.

Meanwhile, man had discovered electricity! Davy demonstrated the possibility of the electric arc lamp early in the 19th century. Its light was as brilliant as the sun but the only power source was storage batteries. These made the light too, expensive for everyday use. When Faraday discovered the principle of the dynamo in 1831, widespread use of electric lighting was possible for the first time. The arc lamp lit streets the world over, from Europe to the far east.

But something still was needed for the home and office. Ar. American genius Thomas Edison was working and the life span of the average lamp has been tripled to 7,500 hours! Even the fluorescent lamp does not hold the final answer to better lighting. Latest discoveries promise to make it as obsolete as the oil lamp. Future lighting will see the increasing prominence of electroluminescence.

Unlike other modern forms of lighting, electroluminescence converts electricity directly into light. There's no need to create heat, as with the incandescent bulb, or radiation, as in the fluorescent light. Because of this, it promises to be even more efficient than presentsources. Possibilities for the near future for this light source include luminous dials on auto and aircraft instrument panels, luminous pictures, night lights, clock faces, and other decorative and useful items normally used in dimly lighted areas. on the problem.

He was convinced he could make a small, practical light by running electricity thru a filament to heat it to luminescence. Other scientists said the idea was impossible. Every known filament burnt out immediately. In 1879, Edison discovered one that worked a sewing thread treated with carbon. The world's first incandescent light was born.

Soon the electric light came into the home. Tho man had left darkness far behind, the search for a better light continued. Progress came rapidly. General Electric's Dr. William D.

Coolidge developed the ductile tungsten filament; Dr. Irving Langmuir introduced the gas filled bulb; Marvin Pipkin inside-frosted the bulb, and later gave it an inside white finish. So the light bulb has become man's most convenient and versatile light source, over a billion being used annually for general lighting in this country. The next great adventure in lighting began in General Electric's Nela Park in Cleveland, in 1934. Scientists were experimenting with the ef- fects of ultra-violet radiation on a phosphorous coating.

They produced an 18 inch long bulb that glowed a brilliant green. It was a fluorescent lamp. Accepted as a laboratory cu-" riosity or a possible decorating light the lamps were made commercially available in 1938. Not many gave them a bright future. Now 20 years old, fluorescent lamps are producing one-third more light than all other light sources combined! Science cut their cost in half, Above: New look" in flourescent lamps is the Power-Groove tube, which has a series of grooves along one side.

These bring a greater amount of phosphor close to the stream of electrons in the tube to be excited and thus to produce more light. Power-Groove lamps give twice as much light as the previous best tubes, and are used where high levels of light are needed. If and when electroluminescence becomes practical for general lighting, here are some uses that have been proposed: walls and ceilings which glow softly or brilliantly, with color and pattern that can be changed almcst at will, luminous draperies and wallpaper, windows that give off light after the sun sets, or light as an integral part of building surfaces. These and similar visions of the convenience, beauty, and economy of electroluminescent panels spur the research to convert such dreams to reality. Thus will be expressed again the ancient pattern man's constant urge to exchange new and better light.

Hi ill 1 Left: Electroluminescent lamps are now feasible for certain specialized applications. This illustration indicates some. In most cases, conventional light sources are being used, but electroluminescence may ultimately do a better job more economically. Below: The dependable high efficiency and long life of fluorescent lamps is due in part to the care used in testing them. Production lamps are thoroly tested in General Electric's engineering laboratories.

Fluorescent life has been lengthened since 1938 from 2,000 to 7,500 burning hours. 1 4 I vi' II II 'SggggFTS. X- Wt fc I a HUM I momc. w.h.m.- inw LA A major change in the internal construction of incandescent light bulbs gives users more light at no increase in wattage. Instead of being horizontal, the light giving filaments are placed in a vertical position, giving an increase ef to 15 per cent in light output, depending on the bulb size.

Now adapted to large bulbs, this development eventually will appear in household sizes. i tV ifi iii A rA ni iSVfcfc. Sfr hUTii fA a.