Fig. 1. Packaging structure of bi-color LED chips. (a) Front view; (b) top view; (c) circuit; (d) physical map

Fig. 2. Power spectrum of bi-color LED chips

Fig. 3. Optical path of experimental setup

Fig. 4. Colorful digital holograms. (a) Without phase shift; (b) with phase shift

Fig. 5. Phase shifting digital holograms with two wavelengths. (a) Without phase shift at 670 nm; (b) with phase shift at 670 nm; (c) without phase shift at 521 nm; (d) with phase shift at 521 nm

Fig. 6. Reconstructed wrap phase maps using two-step phase shifting algorithm. (a) 670 nm; (b) 521 nm

Fig. 7. Experimental results. (a) Dual-wavelength phase map with phase distortion; (b) dual wavelength phase map without phase distortion; (c) 3D surface profile of the tested sample; (d) comparison of the measurement data

Fig. 8. Comparison of stability between the proposed system and the system with two individual light sources