Violet Diode Laser: Sony

Sony announce to play in violet laser diode market some time ago.

As a winner in Blue Ray Disc, Sony must take care of the most important part of optical head - laser diode.

Shiroishi Semiconductor

Shiroshi Semiconductor ,a subsidiary of Sony Corp, focus on semiconductor device.

It's product "BDXL", design for Blue Ray Disc- 405nm, is applied in PS3, Sony Disc recorder on VAIO.......But low yield of diode delay the PS3 time schedule.

Sony previous generation of violet laser diode are less than 300mW.

Recently, Sony release 2 high power violet laser diode:

1.350mW - 3.8mm package

2.400mW - 5.6mm package

(Sample prize: US% 11.9)

Improvement the crystal quality in its GaN epitaxial deposition

End-face coating material used in laser facets

These two increase laser diode power output

Even high as such spec, there are some issues about these products.

High power above 300mW, laser can't sustain high power continuously.

Laser cavity will be melted by the heat of laser (Catastrophic Optical Damage, COD)

Psuedo-Continuous Wave is the solution on this problem.

Laser switch at a 50 percent duty cycle to cool down during off cycle.

Threshold Current <40mA

Operation Voltage~5V

Pulse width :30ns

But even Sony improve its' violet laser diode.

Nichia has higher power violet laser diode which can operate continuously. .....XD

Nichia NDV7112 is 600mW, Φ 5.6mm.

I think Sony must work hard to improve its violet laser diode.