The impact response of an impact hammer is evaluated by means of an optical method. In the method, an object is first levitated using a pneumatic linear bearing, so that it encounters negligible friction, and is then made to collide with the impact hammer under test. The total force acting on the levitated mass (i.e., the product of the mass and acceleration) is measured highly accurately by measuring the Doppler frequency shift of a laser beam reflected from the colliding mass. The velocity, position, acceleration, and inertial force of the mass are then numerically calculated from the measured time-varying Doppler frequency shift. The output signal of a force transducer embedded in the hammer and the measured total force acting on the levitated mass are compared. The future prospects of the proposed method are discussed.