overheating of laser diode

[edoid]

Hello all, I am working a powering a green laser diode. I have managed to power on the laser diode,but even for few seconds of operation the laser diode is heating up so fast that it burns when i touch it. The laser diode I am using is a 50 mW, green laser diode of OSRAM. I am attaching the data sheet of the laser diode in the following link laser diode . I have almost no knowledge in electronics. so I tried this building a laser driver circuit. could anyone please tell me why it is heating up too much?
Thank you in advance

 

[KlausST]

Hi,

I´m doing some math for you (you should have done on youe own)

110mA x 5.8V = 0.64W
The case seems to be big enough to handle 0.64W. And if operated according the datasheet I expect it to take several minutes to heat up.
You are free to add a heatsink to keep temperature low.

From your description: "the laser diode is heating up so fast that it burns when i touch it" I can only guess that you don´t keep on datasheet specifications and overload the diode.

****
To your circuit:
A diode is recommended to be "constant current" driven. The show circuit seems to use constant voltage instead. I doubt the circuit is suitable to drive the diode.

The manufacturer OSRAM knows best how to use their devices (better than random internet sources).
They want you to be satisfied with their products thus they provide all informations you need.

Datasheet says:
Important notes of operation for laser diode
a) Electrical operation
OSRAMs laser diodes are designed for maximum performance and reliability. Operating the laser diode
above the maximum rating even for very short periods of time can damage the laser diode or reduce its
lifetime. The laser diode must be operated with a suitable power supply with minimized electrical noise.
The laser diode is very sensitive to electrostatic discharge (ESD). Proper precautions must be taken.
b) Mounting instructions
In order to maintain the lifetime of the laser diode proper heat management is essential. Due to the design
of the laser diode heat is dissipated only through the base plate of the diode‘s body. A proper heat conduct-
ing interconnection between the diodes base plate and the heat sink must be maintained.
For further application related information please visit https://ams-osram.com/support/application-notes

Did you follow these rules and followed the link?

Klaus