Game Development Reference
11.2.2 Display of stereoscopic images
on a single plane
Irrespective of the technique used in stereoscopic vision, the objective remains the same:
providing a different image for each eye. For this purpose, there are two principles:
we can either put two small screens near the eyes (as in the case of head-mounted
displays) or physically separate the two images displayed on a single screen, which is
at a certain distance from the eyes. In the last category, the principle is based on a
technical device that separates the images so as to show only the desired image to each
eye. The classification given below is thus based on the place where the images are
separated and the type of device used.
126.96.36.199 Separation at the screen level
Auto-stereoscopic flat screen with lights
The screen is a unit of two planes: One is an LCD screen and the other one, right
behind the first, is made of thin illuminated columns separated from each other by
dark zones. There is one light column for two columns of pixels of the LCD screen.
Each light column is spaced out in such a way that an observer in a good position
sees it through the even pixel column with his left eye and the odd pixel column with
his right eye.
In this device, the pixels can be seen only if they are lit up (Figure 11.1).
By displaying the left image on even columns, the left eye of the observer sees the
right image and similarly the odd columns display the right image to the right eye.
Auto-stereoscopic flat screen with lenticular network:
The screen is covered with a lenticular network: A plane made of semi-cylindrical lenses
with axes parallel to the columns of the screen. Their optical characteristics imply that
each eye of the user sees different pixel columns, corresponding to two different images.
For each eye, there are 1, 2 or 4 pixel columns behind each cylindrical lens. If there are
more, the observer sees the continuous scene from different points of view by slightly
Figure 11.1 Principle of vision with auto-stereoscopic screen with lights