A Low-Pressure Sodium Lamp (LPS) is a type of gas discharge lamp that produces light through the excitation of sodium vapor. It operates at low pressure, which allows it to be highly efficient, converting a significant portion of electrical energy into visible light. The light emitted is primarily monochromatic, resulting in a distinctive yellow hue that is often used for street lighting and outdoor applications. These lamps are known for their long lifespan and energy efficiency, making them a popular choice for urban lighting. However, their limited color rendering ability means they are not suitable for applications where color accuracy is important, such as in art galleries or retail spaces.