An optical Kerr gate with the capability of light amplification and a femtosecond opening time in a special fast setup is applied to time-resolved imaging. Transient-induced anisotropy created by a first pump pulse is canceled by the perpendicular-induced anisotropy created by a delayed pump. The transverse resolution of the image is better than 70 μm without degradation due to the optical Kerr effect or optical amplification. Moreover, the rather wide spectral band of the gate offers the possibility of spectroscopic imaging. Three-dimensional imaging of small-signal objects using the gate are demonstrated for several types of transmitting objects hidden behind light diffusers. © 1999 Society of Photo-Optical Instrumentation Engineers.