A system for holographic imaging, said system comprising: a device in holographic imaging, said device comprising: at least two light sources (102, 104, 106; 202, 204; 302, 304; 402, 404), wherein each of the at least two light sources (102, 104, 106; 202, 204; 302, 304; 402, 404) is arranged to output light of a unique wavelength, different from the wavelength of the other light sources, to provide a phase diversity based on the different wavelengths; and at least one holographic optical element (110; 208; 308; 410, 412, 414), wherein the at least two light sources (102, 104, 106; 202, 204; 302, 304; 402, 404) and the at least one holographic optical element (110; 208; 308; 410, 412, 414) are arranged in relation to each other such that light from the at least two light sources (102, 104, 106; 202, 204; 302, 304; 402, 404) incident on the at least one holographic optical element (110; 208; 308; 410, 412, 414) is diffracted by the at least one holographic optical element (110; 208; 308; 410, 412, 414) to form wavefronts of similar shape; wherein the light having been diffracted by the at least one holographic optical element (110; 208; 308; 410, 412, 414) is arranged to form illumination light for illuminating an object (108; 206; 306; 408); and the system further comprising an image sensor comprising light-detecting elements arranged to detect interference patterns formed by object light, having interacted with the object (108; 206; 306; 408), and reference light of the illumination light, wherein one interference pattern is formed for each unique wavelength of light, wherein the holographic optical element (110; 208; 308; 410, 412, 414) is configured to form wavefronts of similar shape such that interference patterns based on light originating from different light sources are spatially shifted less than a size of a light-detecting element of the image sensor. at least two light sources (102, 104, 106; 202, 204; 302, 304; 402, 404), wherein each of the at least two light sources (102, 104, 106; 202, 204; 302, 304; 402, 404) is arranged to output light of a unique wavelength, different from the wavelength of the other light sources, to provide a phase diversity based on the different wavelengths; and at least one holographic optical element (110; 208; 308; 410, 412, 414), wherein the at least two light sources (102, 104, 106; 202, 204; 302, 304; 402, 404) and the at least one holographic optical element (110; 208; 308; 410, 412, 414) are arranged in relation to each other such that light from the at least two light sources (102, 104, 106; 202, 204; 302, 304; 402, 404) incident on the at least one holographic optical element (110; 208; 308; 410, 412, 414) is diffracted by the at least one holographic optical element (110; 208; 308; 410, 412, 414) to form wavefronts of similar shape; wherein the light having been diffracted by the at least one holographic optical element (110; 208; 308; 410, 412, 414) is arranged to form illumination light for illuminating an object (108; 206; 306; 408); and the system further comprising an image sensor comprising light-detecting elements arranged to detect interference patterns formed by object light, having interacted with the object (108; 206; 306; 408), and reference light of the illumination light, wherein one interference pattern is formed for each unique wavelength of light, wherein the holographic optical element (110; 208; 308; 410, 412, 414) is configured to form wavefronts of similar shape such that interference patterns based on light originating from different light sources are spatially shifted less than a size of a light-detecting element of the image sensor.