An electromagnetic wave analyzer determines intensity and phase characteristics of an electromagnetic wave such as an ultrashort laser pulse. The analyzer passes the electromagnetic wave through a Fresnel biprism that produces a probe pulse and a gated pulse. The probe pulse and the gated pulse intersect and interact in a nonlinear optical medium, such as a second harmonic generating (SHG) crystal. The nonlinear optical medium then time gates and frequency filters the electromagnetic wave producing an input pulse gated signal. A lens maps delay in a horizontal direction and crystal output angle in a vertical direction. A camera detects the output of the lens and creates a spectrogram of the electromagnetic wave.