MITSUBISHI

MITSUBISHI LASER DIODESML4XX14 SERIESFOR OPTICAL INFORMATION SYSTEMSI Far - fIeld patternThe ML4XX14 laser diodes lase in fundamentaltransverse (TEoo) mode and the mode does notchange with the current. They have a typicalemitting area (size of near-field pattern) of 1.8 x O.7 I.l rn'. Fig.7 and Fig. 8 show typical far- fieldradiation patterns in ·parallel" and ·perpendicular"planes.The full angles at half maximun points (FAHM)are typically 13· and 33· .00-S~::J01:g.,.2:.11i~Fig. 7 Far - field patternsin plane parallel to heterojunction (J /I1.0all5mW0.5 J'/0-30e.JV Xl3mWVlmWo 30Off- axis angle (deg.)Fig. 8 Far- field patternsin plane perpendicular to heterojunction (J.L1. 0 ;---,-----,,,..----,----,O.L::Ja5o~ 0.5r----+--+-~~~~--~---;g~JOff- axis angle (deg.)m LIght output vs. monitoring output characteristicThe laser diodes emit beams from both of theirmirror surfaces, front and rear surfaces. The rearbeam can be used for monitoring power of frontbeam since the rear beam is proportional to thefront one. Fig.S shows an example of light outputvs monitoring photocurrent characteristics. Whenthe front beam output is 3mW, the monitor outputbecomes 1.0mA.Fig. 9 Light output vs. monitoring output current54~-500- 3.,;::J~::J01:~2lV//LLo o/0.5 1.0 1.5Monitoring output. 1m (rnA)• MlTSUBlSHI"ELECTRIC 2-55