The L90 rating, as applied to LEDs, denotes the approximate duration (typically in hours) within which an LED light source is expected to diminish to 90% of its original lumen output. Essentially, it represents the time it takes for the LED to experience a 10% decrease in brightness, reaching 90% of its initial light emission.
For instance, if an LED holds an L90 rating of 50,000 hours, it signifies that after roughly 50,000 hours of continuous operation, the LED’s brightness will have declined to 90% of its original level. It’s important to understand that the L90 rating serves as a means to assess the LED’s lumen preservation over time, aiding in the estimation of its functional life and performance sustainability within various lighting applications.
LED manufacturers and lighting industry standards commonly specify L90 ratings in technical data sheets, enabling lighting designers and users to make well-informed choices when selecting LED products for specific applications. Moreover, L90 values are frequently utilized in lighting design computations to gauge the expected light output of an LED source over time and its anticipated lifespan before encountering a particular degree of lumen reduction.