With the development of technology, the resolution and angle of view of the above automatic stereoscopic display technology are also promoted in different ways. However, the traditional auto stereoscopic display technology still has two problems: Convergence - focus adjustment conflict (Convergence-Accommodation Conflict, or convergent adaptation conflict); no motion parallax or motion parallax is not perfect.
Convergence refers to the binocular visual axis convergence, when the object from the eye near the convergence angle is bigger, the human eye can be obtained by adjusting the angle of the depth of information. The convergence makes the human eye focus on the object.
Figure 12 shows the real observation and stereoscopic display image when viewed the vergence and focus adjustment. When the human observation object, convergence distance and focal length is the same. But when observing the traditional two or multi view 3D images.
The human eye can perceive the depth information of the 3D image by adjusting the rotation angle. Since the two images are displayed on the display screen, the convergence makes the eyes focus on the display screen, not the 3D image.
At this time, convergence distance and focal length is different, which can cause visual fatigue of human eyes.
Motion parallax refers to the changes in the image on the retina caused by the eye movement of the observer. Since the two view 3D display technology contains only two perspectives, there is no motion parallax.
The multi view 3D display technology contains only discontinuous motion parallax. This is because only when the eyes move to the adjacent observation area, the picture on the retina changes.
To solve the problem, researchers have proposed Super Multi-View Display (SMV).
As shown in Figure 13, super multi view display technology to imitate the human eye in the observation of natural objects, there are at least two images from the perspective of a slightly different light into a pupil at the same time, so the eyes can focus on 3D objects, rather than display, can ease the conflict of convergence - focus adjustment. Because the pupil diameter of human eye is in the order of several millimeters, so the display device needs to produce many (256 or 512) perspectives to meet the above multi view display conditions.
The natural 3D display system in Figure 14 is shown in 256 perspectives. The system uses 16 LCD panels (1024 x 768, 2.57 inches) and 16 projection lenses to achieve a natural 3D display system with 256 perspectives. Among them, the pitch of the observation area is 1.31mm in the horizontal direction.
Therefore, the system has a smooth motion parallax, and the human eye can focus on the 3D image. In addition, the resolution of the 3D image is 256 * 192, and the display size is 10.3 inches.
The display system shown in Figure 15 shows the display system of 256 perspectives