Everyone in LED lighting industry know the lifetime of LED light, but do you know how to indicate the end life and related lifetime? L and B can help you to know clearly.
L defines the percentage of lumen comparing with the initial lumens. B value means the failure data at the L data. So LB value indicate the real lifetime at a certain hours.
Like L90B10 at 50,000 hours means the LED lamp keeping 90% lumen from initial lumen and only 10% light failed to reach 90% lumen. You can get clearly L70B50 means only 50% lamp survive at 70% lumen remaining at 50,000 hours. So L70B50 light decay is faster than L90B10.
From the data, L100B0 is the best quality, but it's impossible to get that. So from good quality to bad, that is L90B10, L80B10, L70B50 like this.
Now are you clear the LB value?