question about externally modulated laser diode

Describe the need for power control and temperature for an externally modulated laser diode. Give Schematic diagrams of a power control and a temperature control circuits. explain their operation principles.

Can Anyone have any hints given to me. Thank you

Externally modulated with what, a Mach Zender? If I recall correctly, a Mach Zender modulator is polarizaton sensitive. So you are trying to keep the temperatures constant so that the polarization does not rotate. Also, I think the control voltage for a Mach Zender changes dramatically if the temperature changes.

Rich
www.MaguffinMicrowave.com

I believe he's refering to the laser-diode direct modulation. You mean a laser diode as a bare element or a laser-diode module (like in a butterfly package)?