Adult text:
In the1960s GE developed a process to make a type of aluminum oxide tubes which could then be used in a high—pressure sodium (HPS) lamp for production. They coined the brand name Lucalox for this product from the tube's description: transLUCent ALuminum OXide.
These lamps produced about twice as much "seeable" light for the same wattage (>100 lumens/watt) as the mercury vapor lamps in part because they're decidedly yellowish by comparison and yellow is the color our eyes are most sensitive to. This is why fire—engine—red is now most often fire—engine—yellow.
This 400—watt Lucalox was manufactured by GE c. 1969. At that time the only local HPS streetlighting was a one—block strip on Mayfield Road adjacent to the then relatively new Severance Shopping Center in Cleveland Heights. Now nearly all area streetlighting is these lamps.
These lamps produced about twice as much "seeable" light for the same wattage (>100 lumens/watt) as the mercury vapor lamps in part because they're decidedly yellowish by comparison and yellow is the color our eyes are most sensitive to. This is why fire—engine—red is now most often fire—engine—yellow.
This 400—watt Lucalox was manufactured by GE c. 1969. At that time the only local HPS streetlighting was a one—block strip on Mayfield Road adjacent to the then relatively new Severance Shopping Center in Cleveland Heights. Now nearly all area streetlighting is these lamps.
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High Pressure Sodium Lamp
High Pressure Sodium Lamp