Multi-spectral digital holography with high-speed wavelength switching and high-speed camera

Digital holography is now often used for biomedical imaging because of its ability of post-computational focusing and the quantitative phase imaging of a transparent biological cell. The spectral information is also important to observe the functional property and the structure of a biomedical cell. In the multi-spectral digital holography, a target is illuminated by light with each wavelength, the corresponding interference fringes are recorded, and then the image reconstruction iterates for each wavelength. The most common method is to use the wavelength switching, but when an object is changing temporally, the wavelength switching should be faster than the changing speed of the object. In this paper, we demonstrate a capturing method of the digital holography with fast wavelength switching based on a white-light continuum laser with acousto-optic modulator and a high-speed camera.