The computer screen is flat and two-dimensional. The reason why we can enjoy the real three-dimensional image is that the difference in color and gray level when displaying on the computer screen makes the human eye have a visual illusion and perceive the two-dimensional computer screen as a three-dimensional image. Based on the knowledge of chromatics, the protruding part of the edge of a three-dimensional object generally presents a high-brightness color, while the concave part presents a dark color because it is blocked by light. This understanding is widely used to draw buttons and 3d lines in web pages or other applications. In the concrete implementation, two 2d characters with different colors can be drawn in different positions with exactly the same font. As long as the coordinates of two characters are appropriate, 3d characters with different effects can be produced visually.
Mainstream naked-eye 3D display technology
At present, the main naked-eye 3D display technologies are improved on the basis of the following two technologies. One is parallax barrier technology, and the other is cylindrical lens technology. (The following technical data are referenced from the microcomputer official website. )
A. parallax barrier technology
I still remember my high school physics friends. They should know that polarized glasses are widely used when showing 3D movies in cinemas. Parallax barrier technology (also known as parallax barrier or parallax barrier technology) is somewhat similar to the polarized glasses method, but one needs to pass through glasses and the other does not. Parallax barrier technology was developed by engineers of Sharp European Laboratory after ten years. The realization method is to use switch LCD screen, polarizing film and polymer liquid crystal layer, and make a series of vertical stripes in 90 direction by using liquid crystal layer and polarizing film.
These stripes are tens of microns wide, and the light passing through them forms a vertical fine grating pattern, which is called "parallax barrier". This technology makes use of parallax barrier between backlight module and LCD panel. In stereoscopic display mode, when an image that should be seen by the left eye is displayed on the LCD screen, opaque stripes 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 stripes will block the left eye, and the viewer can see the 3D image by separating the visual images of the left eye and the right eye. Defect: Because the backlight is blocked by parallax barrier, the brightness will also decrease, so it is difficult to see a high-brightness picture. In addition, the resolution will be inversely proportional to the increase of images played by the display at the same time, resulting in a decrease in clarity.
Representative manufacturers and products applying this technology include naked-eye 3D mobile phones released by Sharp and 3DS game consoles of Nintendo.
B. cylindrical lens technology
The technology of lenticular lens is also called lenticular lens or microcolumn lens. Compared with parallax barrier technology, its biggest advantage is that the brightness will not be affected, but the viewing angle width will be slightly smaller. Its principle is to add a 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, so that the pixels of the image under each cylindrical lens are divided into several sub-pixels, so that the lens can project each sub-pixel in different directions. So when you look at the display from different angles, you will see different sub-pixels. However, the gap between pixels will also be enlarged, so sub-pixels cannot be simply superimposed. Let the cylindrical lens and pixel column not be parallel, but form a certain angle. In this way, each group of sub-pixels can repeatedly project the viewing area instead of just projecting a group of parallax images.
The reason why its brightness will not be affected is that the cylindrical lens will not block the backlight, so the brightness of the picture can be well guaranteed. However, because the basic principle of 3D display is still similar to parallax barrier technology, the resolution is still a difficult problem. At present, some panel manufacturers plan to produce ultra-high resolution panels for 3D. If economies of scale are realized, the resolution problem will be greatly alleviated.