The fluorescent
lamp was invented by Dr. G. E. Inman of General Electric, with
the introduction of a practical fluorescent lamp in 1934. This
lamp was not released until 1937, after the mass-production system
was completed.
We sent three engineers (Buntaro Fujita, Saburo Iwa and Jinzo Todoroki)
to GE in 1939 to help get our fluorescent lamp business operations
underway. These three engineers received technical training directly
from Dr. Inman. In 1940, they succeeded in building pilot fluorescent
lamps. However, all parts were hand-made, following GE's instructions.
Since no base for fluorescent lamps was available at that time, we
used a 4-pin base designed for vacuum tubes.
As we were nearing completion of a fluorescent lamp, we heard that
Japanese painter Eisaku Wada was seeking a bright, but cool light
source. He needed the light to reproduce murals of Horyuji temple
as part of the anniversary event for Japan's imperial era 2600. We
offered the fluorescent lamp, and it was adopted. On August 27, 1940,
136 prototype 20W daylight fluorescent lamps were installed. To prevent
flickering, flicker-free lighting for a double-tube lamp was used.
This day marked the first practical use of fluorescent lamps in Japan.
Fluorescent lamps lit for
the first time (August 27, 1940)
Horyuji temple: A letter
from the chief priest Kaen Ono and a fluorescent lamp stand
In 1941, 15W and 20W daylight fluorescent lamps
were released as a fluorescent discharge lamp, the Matsuda Fluorescent
Lamp. Both 15W and 20W lamps had tube diameters of 38 mm and had
respective overall lengths of 435 mm and 580 mm. These lamps were
half as bright as modern fluorescent lamps.
In 1942, production of daylight fluorescent lamps increased to about
2000 per month. In 1944, however, production of daylight fluorescent
lamps was suspended for the increased demand for munitions. The factory
burned down during the war, just before the completion of an automatic
exhaust machine for production.
During the war, 20W daylight fluorescent lamps were to light submarines,
since it gave of very little heat. The 12W green fluorescent lamp
was used for landing lights on aircraft carriers, due to its high
impact resistance. Almost all other fluorescent lamps were delivered
to the navy and used as shrouded lamps.
After the war, the Horikawa-cho factory, the production base for
vacuum tubes, was moved under the direct control of headquarters.
In 1946, the factory began production of light traps to establish
a new foothold on production of general-purpose fluorescent lamps.
In 1948, we resumed production of daylight fluorescent lamps. In
1949, we developed a highly efficient white lamp using an improved
fluorescent material. We also devised a 40W fluorescent lamp with
high light output. Lit at a trade exposition held in Yokohama, this
lamp attracted much attention from the visitors. We made further
improvements, including corrective measures following discovery that
the fluorescent material used at that time was toxic. In 1952, we
succeeded in increasing the brightness of our fluorescent lamps to
world-class levels. Average service life was doubled to 3000 hours,
and the problem of blacking at the edge of the tube was reduced.
In 1953, we incorporated an early service life estimation method
into our quality control system. We researched every kind of cathode
material, eventually developing a new long-life cathode material
that would replace the heat-resistant oxide cathode announced in
the US. In 1955, we boosted average life to 7500 hours. Our fluorescent
lamps were now equal to products from the world's leading manufacturers,
both in life and brightness.
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Appearance |
 The
first Japanese-made fluorescent lamp (1940)
 Fluorescent
lamp stand (1940)
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