STEREOSCOPIC 3D PROJECTION SYSTEMS
In Stereoscopic 3D projection technology two images, seen from the perspective of the left and the right eye, are projected simultaneously. The frequency of projecting the images is 60 times per second for each eye and covered alternately by the shutter-glasses.
The screens for 3D stereoscopic projection can be either straight or curved (surrounding the viewer). The use of omni-directional screens enables us to have the feeling of immersion, which means we can immerse ourselves completely in the projected reality.
Rules of 3D Projection
Because of eye-spacing (the distance between the right and the left eye, which is usually 4 - 6 cm), each eye has slightly different perspective. Two different images are sent to our brain. The difference between these diverse images is called a parallax and it is interpreted as depth. Stereoscopic projection is based on the same rule: two slightly different images are projected on the screen. Thanks to the system the image on the left can be seen with the left eye and the image on the right can be seen with the right eye. The producer of the system - Barco firm, guarantees high quality of separation, enabling full sharpness of vision and elimination of blur for 3D projections.
In our offer we have a full range of high tech projectors, covering all projection technologies – LCD and DLP for passive and active stereo applications. Optional high-quality application, used for specific optimization of multi-screen stereoscopic projection on flat, curved and spherical screens, is a result of long-term scientific research.
The solutions of projection systems include:
optimization of screens and mechanics,
high quality 3D glasses,
software for dedicated image distortion and easy regulation and conservation.
The producer of the systems has documented high quality installations for the most demanding 3D market in the world.
Passive 3D Projection System
The user of the system watches the screen wearing glasses with two polarized opposite filters - one for the left eye and one for the right eye. The light of each of the two displayed pictures is polarized and passes only through a suitable left or right filter. Depending on the budget, infrastructure conditions and preferences of the user, passive projection system is executed by means of one or two projectors on 1 screen
Active 3D Projection System
The user of the system watches the image displayed by the projector using active 3D glasses. The glasses are equipped with LCD shutters, controlled by IR wave. Their work is synchronized with the work of the projector. At the time when the projector displays an image for the left eye, an active shutter for the right eye is closed, and vice versa.
In the case when one projector is used for the screen, devices capable of projecting images of very high refresh rate should be used so that the viewer would not observe the flash during shifting of the shutters.
Circular and Linear Polarization of Light
Light wave rotates in any direction. The specific orientation at a time determines the polarization of the light wave. Passing through the polarizer, not polarized light shows us only one of its orientations. Setting up polarity for the left eye and for the right eye opposite to each other, we can direct different kinds of information to the left eye and to the right eye creating in this way a perception of depth. The human eye itself is largely insensitive to polarization and that's why during the process of reversing the polarity, we wouldn't notice any changes in the actual image we see.
Linear Polarization of Light
If the light is polarized in one direction (N / S, and W / E, or diagonally) we have to do with linear polarization. When there is a change in orientation of linearly polarized glasses, for example by tilting the head, the orientation of polarization does not match the polarization of the filter installed on the projector. The result of such a situation will be a waste of stereo information received by the viewer. Nevertheless, the linear polarization is a cost-effective technology producing excellent image separation between the left and the right eye for stereoscopic applications, where the possibility of tilting the head is limited.
Circular Polarization of Light
In circular polarization, the viewer can tilt the head and change the viewing angle to the stereoscopic screen, because the light is not polarized in one direction. This high quality technology requires great precision and perfect matching between the polarizing filters in the light path of the projectors and the people in glasses. It is recommend to use round glasses.
Passive 3D glasses are ideal solution for large audiences because they are easy to use and comfortable to wear.