Is it possible to create a monostable multivibrator (one shot) by using a couple of AA batteries instead of a permanent power source? Trying to create a toy gun with a cheap laser pointer attached on it, so when the trigger is pulled it shoots the laser for a few seconds (or for however long the capacitor can hold the charge) rather than holding the trigger to simulate the same effect, and making it so it doesn't need to be plugged in.
If you provide power to a circuit that's the correct voltage and can provide enough current, then it will work.
I believe you meant to use only 1 switch which will trigger laser during a certain time isnt ?
well look for monostable theory then look on how to activate (sort of) your load... I think you can play with capacitors to guarantee that when you switch on, it will stay that way until T passes... so you´d need only one pulse buton
you can also read here about POR (power on Reset)
in the easiest scenario you can trigger a 555 after that schmitt
otherwise study how to make it with 2 or 3 transistors...
The 555 monostable is okay, but be aware that it
is retriggerable so the output will stay HIGH as
long as the trigger input is LOW. The trigger pulse
must be shorter than the output pulse width.
Herb