hi woodsman,
To run your laser from 9v battery rather than a 3v battery, providing the
current the laser draws from the battery is 1.27mA.[this seems low ???]
Then you have to drop 6v across a series resistor, so 6/0.00127 = 4724 ohms
the nearest preferred value is 4700R.
Place a 4K7 resistor in series with battery positive to the laser positive input.
Regards
EricG
Note: dont assume that AA batteries give 1.5v , alkaline will only give 1.2v
also check your 9v battery, [ PP3 type] for voltage when you have got your resistor connected.