Calculation of the ligetime of high-power λ = 0.98 μm heterolasers

The lifetime of high-power (430 — 460 mW, λ = 0.98 μm) heterolasers was investigated at T = 70°C. Slow degradation as well as sudden failure, characterised by a lognormal distribution, were observed. A statistical calculation was made of the maximum lifetime of heterolasers: it was found to be 5430 h at 70°C for a pump current of 1 A.