Decrease in Laser Power: Why Is It Happening?

[nordmoon]

Hi, So I am working with measurements using a laser. What I have noticed is that the power of the laser decreases from the time we start the laser until maybe an hour later.

Today I noticed it has decreased 10%, from yesterday, which I think sounds like a lot.
Does the laser have to warm up and become stable Before operation? The laser is a laser diode.

 

[f95toli]

How is the temperature of the diode controlled? I.e,. are you using a "proper" driver or are you just driving it with a normal current source?
Laser diodes are sensitive to temperature which is why "proper" drive electronics includes a temperature controller.

 

[nordmoon]

How is the temperature of the diode controlled? I.e,. are you using a "proper" driver or are you just driving it with a normal current source?
Laser diodes are sensitive to temperature which is why "proper" drive electronics includes a temperature controller.

Ok I see, that makes sense. I forgot about the temperature sensitivity. As far as I can see it only have a power source and pulse generator. No, there is no 'proper' driver. How would a temperature controller look like? What would it consist of?

 

[f95toli]

Commerical versions look like this

https://www.thorlabs.com/navigation.cfm?guide_id=2107

However, these will only work if your diode is an a mount which can be used with a temperature controller.

(btw, I am not an expert in this area; but I do use laser diodes from time to time)