To Fluoresce, Or Not To Fluoresce?

To fluoresce, or not to fluoresce?  This is the eternal question every true admirer of neon must eventually confront.  The difference between fluorescent (or phosphor-coated) tubes and non-coated neon tubes goes basically undetected by almost everyone outside the small cadre of neon practitioners, professionals and enthusiasts.  But once recognized, the two kinds of tubes are a world apart.


A burger joint on White Plains Road in the Bronx.  Pinkish tubes above demonstrate uniform glow of fluorescent/phosphor-coated neon; uncoated tubes below show the classic look of clear glass tubes.  (T. Rinaldi)
 
Up through the early 1930s, neon signs used clear or tinted glass tubes that offered a limited range of colors.  This changed in about 1933, when tubes lined with fluorescent or phosphorous coatings became available to sign makers.*

 
Display wall at Let There Be Neon.  The introduction of fluorescent/phosphor coated tubes gave neon shops a much wider range of colors from which to choose.  (T. Rinaldi)
 
I confess that I don't have a particularly great handle on the science involved here.  Scientists had long known of minerals that could be made to glow under the right conditions.  In the 1920s and 30s, researchers developed a means of applying a pulverized coating of these minerals to the inside of glass tubes used for neon signs.  When energized, both the gas within the tube and the applied layer of phosphorous minerals would come aglow. This innovation presaged the development of what are now known as fluorescent lamps, first introduced commercially by GE in 1938, which work on a similar principle.
 

Da-Nite Neon display ad from the 1940 Manhattan Classified Telephone Directory, featuring fluorescent tubes. (N-YHS)

The neon industry quickly embraced fluorescent coated tubes for two reasons.  First, they glowed more brightly than uncoated tubes.  Second and more significantly, the coatings could be made to glow in a range of colors.  New phosphorous colors have been continuously introduced since the 1930s, giving neon shops hundreds of colors and hues to choose from.  In the 1930s, the neon industry typically referred to coated tubes as "fluorescent."  The introduction of standard fluorescent lamps in 1938 muddled the nomenclature a bit, and now coated tubes for neon signs are more commonly referred to as "phosphorous" or "phosphor coated," probably to avoid confusion with off-the-shelf fluorescents.


Uncoated tubes on a c. 1930 Flexlume sign at the American Sign Museum in Cincinnati. (T. Rinaldi)

Despite the obvious advantages of fluorescent/phosphor-coated tubes, uncoated tubes never went away.  In fact, somewhat counterintuitively, neon professionals and enthusiasts almost universally seem to prefer their tubes uncoated.  While coated tubes glow in bright uniformity, uncoated tubes offer more visual complexity, glowing with more brilliance in the center of the tube where the gas is most dense, the candlepower dimming toward the periphery as the gas thins out.  From up-close, I sometimes find myself captivated by the light of an uncoated tube in rather the same way that one gazes into the open flame of a campfire.  Often, one can observe pulsing fluctuations in the light: the science, though less sophisticated than that at play in a coated tube, seems somehow more accessible.


Radio City marquees emerged from restoration with fluorescent tubes. (T. Rinaldi)

Customers, however, more often prefer the brightness and color range of coated tubes.  In sign restorations, the more marketable appeal of fluorescent tubes sometimes trumps historical accuracy.  This was the case in the restoration of the Radio City Music Hall marquee, whose red and blue tubes emerged from restoration some years ago somewhat brighter and more vivid than they had been originally, thanks to the use of fluorescent tubes that were not available when the sign was first installed in 1932. 


The Wonder Wheel. (T. Rinaldi)

In Coney Island however, two of New York's oldest signs retain their original look with clear glass tubes intact.  The tubes themselves have likely been replaced many times over, but the uncoated blue and red glow of the old-old signs at Nathan's and the Wonder Wheel are true to their period form, each installed around 1930.  (Later signs at both establishments make a good contrast with fluorescent tubes in various colors.) 


Nathan's. (T. Rinaldi)


With their unadulterated hues of classic red and blue, these two early signs demonstrate the look of the first generation of neon signs installed before the early 1930s.  As of February 2013, Nathan's remains closed in the wake of Hurricane Sandy. Here's hoping they'll both come back to light in time for summer.
 
*In a 1976 article, William Anthony, Jr. cites a 1933 patent issued to a German inventor called Erich Koch; Arthur Bright, Jr.'s book The Electric-Lamp Industry of 1949 dates the innovation to a French patent issued to Jacques Risler in 1926.
 
FOR MORE, SEE:

• "Sales Advantages of Fluorescent Tubing," by J. Kurtz in Signs of the Times Magazine, April, 1938.
• "A Brief History of the Sign Industry," by William Anthony, Jr., in Signs of the Times Magazine, September, 1976.
• "The Electric-Lamp Industry," by Arthur Bright, Jr.,  1949.

IN OTHER NEON NEWS:
 
• Bad news from upstate NY, by way of Rob Yasinsac: In Canajoharie, the Beech-Nut sign, high point of interest on the New York State Thruway, is no more.
• And, via Project Neon and elsewhere, more bad news from Brooklyn: Hinsch's seems poised to bite the dust once and for all by the end of February.