Stereoscopic image display device comprising transmissive liquid crystal display element

A display device comprising:

• an image display element which controls transmission of light to alternately display different first and second images on a first surface and a second surface thereof, respectively;
• two surface light sources which are respectively arranged on both sides of the image display element, which irradiate the display element with illumination lights, and which emit first and second image lights, that respectively correspond to the first and second images and that are transmitted through and exit from the image display element, therethrough in respective directions inclined to a normal line of the image display element by a predetermined angle;
• a first optical system which leads the first image light that corresponds to the first image displayed on the first surface of the image display element, and that is emitted in one of the respective directions inclined to the normal line of the image display element by the predetermined angle;
• a second optical system which leads the second image light that corresponds to the second image displayed on the second surface of the image display element, and that is emitted in another one of the respective directions inclined to the normal line of the image display element by the predetermined angle;
• an image combining element on which the first and second image lights led by the first optical system and the second optical system are alternately incident, and which emits combined image light for displaying a combined image formed by combining the first and second image lights to an observation side;
• a display drive circuit which drives the image display element to alternately display the first and second images, that are combined by the image combining element;
• and
• a light source control circuit which controls lighting of the two surface light sources in accordance with display of the first and second images on the image display element.

A display device comprising:

• image displaying means for alternately displaying different first and second images on a first and second surface thereof, respectively;
• first and second surface light source means, respectively arranged on both sides of the image displaying means, for irradiating the image displaying means with illumination lights, and for emitting first and second image lights, that respectively correspond to the first and second images and that are transmitted through and exit from the image displaying means, therethrough in respective directions inclined to a normal line of the image displaying means by a predetermined angle;
• first optical means for emitting the first image light which corresponds to the first image displayed on the first surface of the image displaying means and which is transmitted through and exits from the image displaying means in a first direction inclined to the normal line of the image displaying means by the predetermined angle;
• second optical means for emitting the second image light which corresponds to the second image displayed on the second surface of the image displaying means and which is transmitted through and exits from the image displaying means in a second direction inclined to the normal line of the image displaying means by the predetermined angle;
• image combining means, on which the first and second image lights emitted by the first optical means and the second optical means are alternately incident, for coinciding first and second light paths of the first and second image lights, and for emitting combined image light of a combined image formed by combining the first and second image lights to an observation side;
• display driving means for driving the image displaying means to alternately display the first and second images, which are combined by the image combining means;
• and
• light source controlling means for controlling lighting of the first and second surface light source means in accordance with display of the first and second images by the image displaying means.

A display device comprising:

• an image display unit having a first surface for emitting first image light, and a second surface for emitting second image light;
• a first optical system which leads the first image light emitted from the first surface of the image display unit;
• a second optical system which leads the second image light emitted from the second surface of the image display unit;
• and
• an image combining element on which the first and second image lights led by the first optical system and the second optical system are incident from different sides thereof, and which emits the first and second image lights from one side of said different sides,
• wherein the image display unit includes:
• a transmission type display element which controls transmission of light;
• a first surface light source which includes said second surface, and which emits light into the display element so that the first image light is emitted toward the first optical system from the first surface in a direction inclined to a normal line of the display element by a predetermined angle;
• and
• a second surface light source which includes said first surface, and which emits light into the display element so that the second image light is emitted toward the second optical system from the second surface in a direction inclined to the normal line of the display element by a predetermined angle.