High-power operation of AlGaInP red laser diode for display applications

Abstract

Substantial limitation of output power in AlGaInP based red broad area (BA) laser diode (LD) originates from an electron thermal overflow from an active layer to a p-cladding layer and fatal failure due to catastrophic optical mirror degradation during the LD operation. New red BA-LD was designed and fabricated. The LD chip had triple emitters in one chip with each stripe width of 60 um, and was assembled on 9.0 mm -TO package. The LD emitted exceeding 5.5 W at heat sink temperature of 25 °C and 3.8W at 45 °C under pulsed operation with frequency of 120Hz and duty of 30%, although the current product, which has a 40 um single emitter chip assembled on 5.6mm -TO, does 2.0 W at 25 °C. The lasing wavelength at 25 °C and 2.5W output was 638.6 nm. The preliminary aging test under the condition with the operation current of 3.56A, CW, auto-current-control mode (ACC), and the heat sink temperature of 20 °C (almost equal to the output of 3.5 W) indicated that the MTTF due to COMD was longer than 6,600 hours under CW, 22,000 hours under the pulse with duty of 30%.

18.2: Invited Paper: Single‐emitter 638nm laser diode with 4W continuous wave power

“…On the other hand, those under pulse show nearly straight up to operation current of 3A from 15℃ to 65℃. As the current increases to 5A, saturation appears at 55℃ and the power peaks out 2.5 W, which is 2.5 times stronger than the red laser diode with 40um stripe width from Mitsubishi [2].…”

Speckle contrast evaluation of multi-emitter broad area 638-nm red laser diodes

“…The LD has an insulator stripe-type structure. The number of emitters is determined by the number of insulator stripes [1][2][3][4]. The single emitter we reported has a stripe with 40 μm width.…”

“…We have developed and reported several 638 nm broad area (BA) LDs. A multiple stripe structure such as dual and triple emitters is adopted to achieve high-power and highly reliable operation in the LDs based on previous studies [3,4].…”