Image quality improvement of digital holography by superposition of reconstructed images obtained by multiple wavelengths.

A method to improve the image quality of a digital holographic reconstructed image by means of speckle reduction is proposed. The size and position of the speckles are changed according to the wavelengths to record a digital hologram. By superposing reconstructed images with different wavelengths, the effect of speckle is reduced so that the image quality is improved. Optical experiments are given to confirm the proposed method.