An image creation unit of a server creates and stores a plurality of phase images or the like having different resolutions on the basis of holographic data collected by a measuring terminal. In response to an image transmission request according to an operation, an image transmission processing unit of the server extracts data of an image corresponding to an observation range after the movement from an image of an appropriate resolution and transmits the data to the browsing terminal. In the browsing terminal, a display image is formed by overlaying a high-resolution phase image corresponding to only an observation range to be displayed on low-resolution phase image of an observation target area.