32 × 20 [O III] image of SNR 0540-69.3 obtained with NTT/EMMI in 1996 using the narrow [O III]/0 filter centered at the rest wavelength of [O III] λ5007. The bright extended object in the center of the image is the central part of the remnant containing the pulsar. The white lines marked by numbers show the slit positions used at the spectral observations of the SNR with NTT/EMMI (2) and VLT/FORS1 (1 and 3). The areas marked “F1–F5” show the positions of five H II regions identified from the spectral observations and described in the text. A 100″ × 100″ black box outline the region shown in Fig. 2.