Three-dimensional image forming apparatus and three-dimensional image forming method

A three-dimensional image forming apparatus comprising:

• an image extractor which selectively extracts a specific portion from an image to be printed;
• an image converter which converts the specific portion extracted by the image extractor into an image of a color having a thermal energy absorptivity higher than those of portions other than the specific portion;
• a conversion image printer which prints a conversion image converted by the image converter on a foaming layer side surface or a back face of a thermally expandable sheet;
• a light source unit including a light/heat irradiator having a light/heat irradiation temperature of a first body part lower than that of a second body part, wherein a three-dimension image is formed by expanding the foaming layer side surface corresponding to the conversion image with thermal energy generated in the printed conversion image by light/heat irradiation on the thermally expandable sheet printed with the conversion image by the conversion image printer;
• and
• a conversion image printing density controller which controls when a degree of expansion of the thermally expandable sheet is equally set over the specific portion, an image density of an area in the conversion image of the specific portion corresponding to the first body part of the light/heat irradiator to be higher than an image density of an area in the conversion image of the specific portion corresponding to the second body part of the light/heat irradiator.