Measuring method of impulse of single pulse laser with torsion pendulum

Laser focuses onto a target, producing an ablation back-jet, which provides a micro-impulse. The torsion pendulum micro-impulse measure method was studied. The equations of oscillation were put forward under the thrust of ablation back-jet. And the integral equation of impulse was presented under the action of single pulse laser. Based on the discrete integral equation of impulse, the calculation method of single pulse impulse was proposed. Furthermore the error of calculation was analyzed. This method could be used in engineering measure and calculation for single pulse impulse with torsion pendulum.