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Types of Sodium Lighting: LPS vs HPS Explained
Compare Low Pressure Sodium (LPS/SOX) and High Pressure Sodium (HPS/SON) lighting, including efficiency, color rendering, spectrum, applications, and the key differences between these two sodium vapor technologies. Read more...
History of Low Pressure Sodium (LPS/SOX) Lighting
Low Pressure Sodium (LPS) lighting evolved from early sodium vapor experiments into the most efficient street lighting system ever deployed, later replaced by LED but still used in specialized applications. Read more...
How LPS Works
Discover the plasma physics behind low-pressure sodium (LPS/SOX) lighting. Learn how neon-argon Penning mixtures and vaporized sodium generate high-efficacy, monochromatic 589nm amber light. Read more...
What Is Low Pressure Sodium (LPS/SOX) Lighting?
Low Pressure Sodium (LPS/SOX) lighting is a monochromatic 589nm amber lighting technology known for its ultra-narrow spectral output, minimal blue light emission, and high efficiency. This guide explains how LPS lamps work, why they appear yellow, and where they are used—including roadways, observatories, wildlife-sensitive environments, and dark-sky applications. It also compares LPS vs LED lighting and highlights the benefits and limitations of sodium vapor systems for specialized infrastructure and research lighting. Read more...
The Black Fire Experiment: How LPS Monochromatic Light Reveals the Limits of Human Color Vision
Discover how Low Pressure Sodium (LPS) light makes fire appear black — and what this reveals about the unique 589nm monochromatic spectrum of SOX lamps. Includes step-by-step experiment instructions. Read more...