Single picosecond pulses of a Nd:glass laser are used in a single‐pass generator to produce intense ultrashort infrared pulses. Starting from quantum noise, stimulated three‐photon parametric amplification over ∼12 orders of magnitude is achieved in a LiNbO3crystal at a pump intensity of 1010W/cm2. Angular tuning provides a frequency range of 2500–7000 cm−1. High conversion efficiencies exceeding 1% are measured without crystal damage.