Three-Dimensional Display

"High-density directional displaying method"
 Three-dimensional (3D) display is in great demand in many kinds of field such as amusement, broadcasting, and industry, and its market is expanding annually. There’s many kind of 3D displaying method, but each of them has some demerits, which makes difficult to popularize. Demanded factors are
  • No special glasses
  • Stress-Free (Especially for long time watching)
  • Great reality
  • High resolution
We are developing a display which has all of these essentials.
In our study, we use “High-density directional displaying method”. This method calls for a large number of graphics which shows the image of target object from every angle. These graphics are called “Directional-images”. By projecting these graphics by directional rays to a direction which corresponds to its rendered angle, we can see a 3D image. The merit of this method is
  • No special glasses
  • Stress-Free
  • Smooth motion parallax

Fig. 1 High-density directional displaying method.
In order to project directional-images to its direction, we proposed a way that used a holographic screen. Fig.2 shows the way to make holographic screens, and how the 3D image is displayed.

(a)Making of holographic screens
When we cross more than two beams, the interference fringe is made in a crossed position. Holographic media can store the information of the fringe pattern. We interfered two directional beams. These two beams are called “signal beam” and “reference beam”. We recorded the fringe pattern as changing the recording position (1,2,3) and angle of two beams.

(b)Displaying 3D images
When we irradiate reference beam to the recorded medium, the diffracted beam, which has the same information to signal beam, appears. So, the direction of diffracted beam is depends on the irradiating position (and the angle of signal beam recorded at the position). By using holographic screens, we can change the direction of diffracted beams freely. And by modulating reference beam, we can project directional images to the direction correspond to their rendered direction directionally. In fact, we recorded a large number of interference fringe on a medium. But in fig.2, we showed only three positions in order to make the figure easy to understand.



Fig. 2 Hologram screan

Present style
We succeeded to display a single color, 1.4inch size 3D images (fig.3). When we horizontally moved, we can see the image changing correspond to the viewing angle. Fig.4 shows the 3D images. As displayed 3D images provide the binocular parallax, we can see the images stereoscopically.

Fig. 3 3D displaying system


Fig. 4 Displayed images