Fig. 1. Schematic layout of the double-pass grating imaging spectrometer. (a) Schematic of the present method; (b) simulation of the captured image by the proposed method with a snapshot; (c) simulation of the captured image obtained by the traditional grating imaging spectrometer with a snapshot.

Fig. 2. Schematic layout of the simulation system using the software Zemax OpticStudio.

Fig. 3. Result of the simulation system. (a) The input scene; (b) the captured color image of the scene in one shot; (c) the captured gray image of the scene in one shot.

Fig. 4. Spectral image of two semiconductor lasers.

Fig. 5. Result of the experimental system. (a) The scene of a color picture; (b) one captured gray image of the scene in one shot.

Fig. 6. Four spectral filtered images of the target.

Fig. 7. Recovery spectral curves of points A and B, as shown in Fig. 5.