・High speed 500Mbps GaN Green LEDs
and their application to POF communication module.
TOYODA GOSEI CO.,LTD.
R&D CENTER
Yukitoshi Inui
MOST Forum on 23 March 2010 in Frankfurt
10-2
High speed 500Mbps GaN Green LED
Attenuation（dB/km）
● POF（Plastic Optical Fiber） Attenuation ＆ light source
①
②、③、④
①Low attenuation wavelength
480~530ｎｍ
②The emission wavelength of
Green LED is the same as ①.
③The temperature dependence of
central wavelength is a little.
④The temperature dependence of
the emission intensity is a little.
Wavelength（nm）
MOST Forum on 23 March 2010 in Frankfurt
10-3
High speed 500Mbps GaN Green LED
● Temperature dependence of central wavelength
１０ｎｍ
３ｎｍ
・The wavelength change in operating temperature（from 0℃ to 85℃）
is very little （3nm）.
・The fluctuation band is a range of low attenuation wavelength
(from 480nm to 530nm) of POF.
MOST Forum on 23 March 2010 in Frankfurt
10-4
Measurement system of Eye Diagram
＜Measurement condition＞
GREEN LED
・Power –supply voltage : 3.5V (Vf = 3.3V)
・Tx Frequency : 150M/400/500Mbps
・Tx voltage
: 1.0Vp-p
150/400/500Mbps
OSCILLO
PG
Lecroy
Anritsu
POF 1m
oPHY
APD
SCIENTEX
Original PCB
MOST Forum on 23 March 2010 in Frankfurt
10-5
Eye Diagram
＜150Mbps＞
＜400Mbps＞
Because the drive circuit for red LED is used.
＜500Mbps＞
Eye Diagram is good!
MOST Forum on 23 March 2010 in Frankfurt
10-6
Proposal of module by
using GaN Green LEDs
MOST Forum on 23 March 2010 in Frankfurt
10-7
ModuleⅠ
High-speed communication module by using Green LED
It is just changed Red LED for Green LED,
the communication speed can get higher up to
500 Mbps without becoming expensive.
SIDE CAMERA
Green LED
POF
NAVIGATION
FRONT CAMERA
500Mbps
REAR MONITOR
REAR CAMERA
SIDE CAMERA
MOST Forum on 23 March 2010 in Frankfurt
10-8
ModuleⅡ
Bi-directional communication module
Bi-directional single POF communication module
consists of the WDM polymer optical circuit fabricated
by light-induced self-written waveguide techniques,
developed Green LED and a conventional Red LED.
SIDE CAMERA
POF
Bi-directional
FRONT CAMERA
NAVIGATION
REAR MONITOR
REAR CAMERA
Bi-directional
added feedback or control circuit
SIDE CAMERA
MOST Forum on 23 March 2010 in Frankfurt
10-10
Thank you very much
TOYODA GOSEI Co.,LTD.
RESEARCH ＆ DEVELOPMENT CENTER
Yukitoshi Inui
30.Nishinomachi,Kitajima-Cho,Inazawa-City,
Aichi-Pref.492-8540 JAPAN
Phone +81-587-34-3335
FAX
+81-587-34-3309
E-mail：tg22884@toyoda-gosei.co.jp
MOST Forum on 23 March 2010 in Frankfurt