Reflection-type aerial image formation device and reflection-type aerial image formation method

A reflection-type aerial image formation device that uses optical image formation means obtained by overlaying a first optical control unit having a plurality of first light reflecting surfaces arranged parallel at intervals inside a transparent flat plate so as to be perpendicular to one surface of the transparent flat plate on a second optical control unit having a plurality of second light reflecting surfaces arranged parallel at intervals inside the transparent flat plate so as to be perpendicular to the other surface of the transparent flat plate, with the first and second optical control units being overlaid on each other in a thickness direction of the transparent flat plate so as to make the first light reflecting surfaces orthogonal to the second light reflecting surfaces in planar view, characterized by comprising:

• a first reflecting mirror placed on a side of the first optical control unit of the optical image formation means so as to face the first optical control unit at an interval;
• and
• a second reflecting mirror placed on a side of the second optical control unit of the optical image formation means so as to face the second optical control unit at an interval,
• wherein light emitted from display means and irradiating the first reflecting mirror is reflected by the first reflecting mirror to be made incident on the first optical control unit, and light, of the light incident on the first optical control unit, which is reflected once by the first light reflecting surface to be made incident on the second optical control unit and reflected once by the second light reflecting surface to exit from the second optical control unit is reflected by the second reflecting mirror to form an image displayed on the display means into an aerial image, and
• wherein the display means and the aerial image are placed between the first reflecting mirror and the second reflecting mirror.