Image display device and image display method

An image display method of an image display device for displaying a stereoscopic image by using a parallax barrier method,

• the image display device comprising:
• an image display surface on which an image of left-eye image data and an image of right-eye image data are alternately displayed, the image display surface being transmissive;
• an image forming unit including a plurality of optical members having a plurality of strip-shaped patterns with optical properties arranged on a surface located on a back surface side of the image display surface;
• and
• a plurality of strip-shaped light sources adjacent to each other in a width direction of an illumination arrangement surface arranged on the illumination arrangement surface, which is a surface located on a back surface side of the image forming unit, and configured to irradiate the image display surface with illumination light,
• wherein a focal length of the optical member is substantially equal to a distance between a position at which the optical member is arranged and a position at which a slit area of the parallax barrier method is arranged;
• and
• the plurality of light sources having a strip shape are arranged on the illumination arrangement surface so that, out of the plurality of light sources having a strip shape arranged adjacent to each other in the width direction of the illumination arrangement surface, images obtained by forming an image of the illumination light from the strip-shaped light sources on the back surface side of the image display surface by using the optical members included in the image forming unit are in the same position for the light sources having a strip shape every predetermined number based on the parallax barrier method,
• the image display method comprising:
• causing, of the plurality of strip-shaped light sources, a light source corresponding to a light emitting region on the illumination arrangement surface in which the illumination light is generated to emit light;
• forming the slit area of the parallax barrier method with the image;
• and
• controlling the image display surface based on the left-eye image data and the right-eye image data.