PURPOSE: To easily read information by deforming binarized information data and the clock data thereof to prescribed patterns and recording the same as Fresnel holograms.

CONSTITUTION: A data pattern array 10 consisting of the bits binarized with the information to be recorded and a clock pattern array 20 for clocking the periods of the above-mentioned bit patterns are formed adjacently to each other to form an information pattern 30. The patterns 30 are then recorded as the Fresnel holograms on a photosensitive material and a hologram card 1 is produced by the conventional method. The data of the resulted card 1 and the card 1 are irradiated with monochromatic light 4 to reproduce the data pattern array 11 and clock pattern array 12 recorded on a recording medium 3. The data signal and clock signal are read as the signals of 0 and 1 by scanning a photodetector 5.