A paper-like display?

Electronic paper (EPPAPER) is a new generation of display equipment, which is technically characterized by ultra-high contrast, which is higher than that of ordinary paper, so there is no problem in strong sunlight. It saves electricity, only uses electricity when refreshing the screen, and keeps the display when the power is off. Ultra-thin, the thinnest can reach 0. 1mm, similar to paper, can be bent and folded at will, and has good flexibility. What is electronic paper? Electronic paper, also called digital paper. It is an ultra-thin and ultra-light display screen, which means "a display as thin, soft and erasable as paper". When we talk about electronic paper, we will inevitably talk about electronic ink. Figuratively speaking, electronic paper is a film coated with a charged substance, which is electronic ink. This can also be regarded as a very thin embedded remote control display board. It has the following characteristics: (1) Content rewriting. You can rewrite and update words or pictures at will, and you can browse a lot of content; (2) Suitable for naked eye reading. Because of the high contrast, people and images are clear, no matter which direction you look at, it is very comfortable to read; (3) portability. Because the film is light in weight and easy to carry, it can be folded and curled properly; (4) Even in the case of power failure, the display screen can be kept for a long time, and it is very energy-saving when used.

Books, magazines, newspapers and other printed materials are being digitized, and the development of terminals for digital reading is also under way. The problem in this respect is how to make reading and reading feel close to the feeling of using paper. Only "electronic paper" cannot constitute a display. As a necessary condition, it also includes ensuring the contrast between the image part and the non-image part, that is, readability, being able to eliminate or rewrite the original pictures and texts, and the energy consumption for writing and saving the images is low.

Such products are called "electronic paper", "digital paper" or "paper-like display", and the goal is to make a paper-like product. The research is carried out from two aspects: one is to make the display like paper, that is, an electronic display screen in liquid crystal mode or electrophoresis mode, and the other is to make paper like an imaging display, which can erase and write paper.

1.LCD mode

This method takes advantage of the change of molecular arrangement of liquid crystal after voltage is applied, and expresses contrast by adjusting transmittance and changing light direction. Liquid crystal displays on notebook computers and other products are well known to us. The idea of making electronic paper liquid crystal display is to separate the liquid crystal panel from the device for writing images, realize thinness and can be curled to make things like imaging paper. Writing can be achieved by applying light, heat, surface charge and other methods.

2. Electrophoresis mode

This method uses microcapsules that can change the black and white state under voltage to realize image display. The charged white titanium oxide particles and black carbon powder particles in microcapsules move up and down under the action of voltage, thus drawing a black-and-white image. It has the characteristics of ideal contrast and brightness vision, low power consumption, light weight, easy thinning and free shape. In addition, some products use the electrophoresis phenomenon of charged toner to improve the contrast between black and white by increasing the concentration of toner.

3. Rewritable paper

It is made of thermal recording technology commonly used in fax paper and other products, and uses dyes that appear or fade at a specific temperature, thus realizing the rewriting of pictures and texts. No matter from the visual sense or use sense, this product is almost the same as ordinary paper. This rewriting technology has been applied to the electric supermarket's point cards and tram monthly tickets.

4. Reading terminal

The dedicated reading terminal has entered the practical stage. The company has begun to sell special reading terminals as devices for reading digital books, magazines and other materials, some of which are products using microcapsule electrophoretic displays. For example, LIBRIE made by Sony. Because there is no power consumption when the picture is not rewritten, a book 10000 pages can be browsed with four commercially available alkaline batteries, the resolution is 170ppi, the thickness is about 13mm, and the first weight is 200g g. In addition, the machine can also play the characteristics of digital technology and realize sound reproduction, which is expected to be used in language learning and other aspects. Now only monochrome products are displayed, and the price is as high as 40,000 yen (equivalent to about 3,000 yuan). In addition, devices for displaying colors by using paper-like flexible displays or RGB color filters are also being developed. In the future, it can be said with certainty that a part of paper printed matter will be replaced by this electronic display mode. If so, not only the existing printed matter will be replaced, but also the same data will be used to produce and provide services such as electronic information content.