Technology | analysis of naked eye 3D display technology

At present, the naked eye 3D large screen market is hot, and 3D technology is also known as 3D display technology. Naked eye 3D display includes parallax barrier technology, cylindrical lens technology, MLD (multi-layer display) technology and pointing light source technology. The first two are suitable for LED display. Today's Sunrise will take you to learn more about these two types of naked eye 3D technology.

Parallax barrier

Parallax barrier technology is developed by engineers of sharp European laboratory after ten years of research. It was originally designed for liquid crystal display. Its implementation method is to use a switching liquid crystal screen, polarizing film and polymer liquid crystal layer, and use the liquid crystal layer and polarizing film to produce a series of vertical stripes with a direction of 90 °.

 

When applied to liquid crystal displays, these stripes are tens of microns wide, and their light forms a vertical fine grid pattern, Called "parallax barrier" ". this technology makes use of the parallax barrier between the backlight module and the LCD panel. In the stereoscopic display mode, when the image that should be seen by the left eye is displayed on the LCD screen, the opaque stripe will block the right eye; similarly, when the image that should be seen by the right eye is displayed on the LCD screen, the opaque stripe will block the left eye. By separating the visual pictures of the left eye and the right eye, the viewer can see the 3D image. Defect: due to The backlight is blocked by the parallax barrier, so the brightness will also be reduced. It is difficult to see a high brightness picture. In addition, the resolution will also decrease inversely with the increase of images broadcast by the display at the same time, resulting in the decrease of clarity.

When applying this technology to LED display, it is necessary to design and manufacture vertical liquid crystal grating with appropriate size according to the situation. Since the size of LED display is much larger than that of liquid crystal display, it is not difficult to manufacture this specially designed liquid crystal grating, but its application will not be very large, and the cost needs to be calculated.

Cylindrical lens

Another technology called cylindrical lens, also known as biconvex lens or micro cylindrical lens, has the greatest advantage over parallax barrier technology that its brightness will not be affected. Its principle is to add a layer of cylindrical lens in front of the LCD screen, so that the image plane of the LCD screen is located on the focal plane of the lens. There are several pixels under each sub cylindrical lens. The light emitted by the pixels will be refracted when passing through the lens. Due to the different positions of the pixels, the refraction angles are different, so the eyes look at the display screen from different angles and see different images.

In the application of LED large screen, because the plate-shaped cylindrical lens will not greatly block the backlight, the picture brightness will not be reduced much. However, because most of the LED large screens are installed in bright occasions, the plate-shaped cylindrical lens plate has a very strong reflection of external light, giving people the feeling of "a white flower", which not only greatly reduces the contrast, but also affects the image quality. These are deep-seated problems that need to be solved.