An apparatus for displaying a three-dimensional image comprises: a light field generating unit (110), which is configured to receive an incident light beam (112) and generate a three-dimensional light field; and an image revealing medium (120), which is arranged to receive the three-dimensional light field generated by the light field generating unit (110), wherein the image revealing medium (120) comprises a fluid with bubbles or particles suspended in the fluid, wherein the bubbles or particles have a size in the range of 40-500 nm.