OK Mr. Smarta$$ Electrician.
First of all, a Vf of Bluray laser diode is 5 V.
Second, laser diodes require a constant current source, not constant voltage.
Powering one from battery is done via current regulators.
If you powered your bluray from 9.6 V, that means you use some form of LM317 or LM1117 linear step down regulator.
LM317 which is fairly common, has a Vdrop of around 2.5 V.
That means you must have 2.5 V + 5V (laser diode powered) from your power supply.
You can, therefore, use anything from 7.5 V to the maximum of 12 V.
You will notice the datasheet of LM317 saying that it can handle 35 V.
But, with Vf of load of only 5 V, any excess voltage above 7.5 V will turn into heat, because LM317 simply burns of extra voltage as heat.
But I'm sure you already knew that.