Payment app fingerprint security authentication, joint account withdrawal encryption fingerprint authentication... Many fingerprint identification behaviors are expected to be realized in a way of higher security and convenience through under LCD screen (internal) fingerprint identification technology.Due to the opaque characteristics of LCD screen, it is difficult to realize this technology. Nevertheless, many panel and mobile phone manufacturers have challenged LCD off screen fingerprint technology, which is evolving towards high integration, full screen fingerprint multipoint identification and high screen share.Evolution from "off screen" to "on screen"
At present, the off-screen fingerprint identification technology applied to OLED mobile phones has been very mature. Due to the high cost, the selling price of mobile phones is generally high. Although the cost of LCD screen is low, the LCD screen itself cannot transmit light, so it is difficult to realize the fingerprint technology under the LCD screen. Nevertheless, in recent years, many panel and mobile phone manufacturers have challenged the fingerprint technology under the LCD screen and achieved certain results.In May 2019, AU Optronics displayed a full screen optical fingerprint identification LCD screen.In June 2019, BOE revealed that the optical fingerprint sensing technology under LCD screen has been successfully developed. In August 2019, Huawei glory demonstrated the LCD mobile phone prototype equipped with off-screen fingerprint unlocking. It is reported that this prototype is the result of joint development between glory and BOE.
In March 2020, Lu Weibing, vice president of Xiaomi group and general manager of Hongmi brand, announced that Hongmi team had overcome the problem of screen fingerprint, realized screen fingerprint on LCD screen and had mass production.In June 2020, TCL Huaxing announced that it had developed fixed single point on-screen fingerprint technology. It is expected to launch full screen single point on-screen fingerprint technology this year and Full Screen multi-point on-screen fingerprint technology in 2021.In July 2020, the world's first LCD on-screen multi-point fingerprint solution (Ted finger print) developed by Tianma was officially released. The scheme embeds the fingerprint image collector in the TFT display substrate, realizing the integration of touch, display and fingerprint identification.
What is the evolution process from "off screen" to "on screen"?
It is understood that the development of off screen fingerprint is mainly divided into off screen fingerprint (fixed single point), on-screen fingerprint (full screen single point), on-screen fingerprint (Full Screen multi-point Ted embedded), etc. Off screen fingerprint identification includes capacitive, optical and ultrasonic types. However, due to technology and cost, most of the products equipped with this technology can only realize single point fingerprint identification in a fixed area. Now, the latest R & D achievement - on-screen multi-point fingerprint solution adopts the optical fingerprint identification mode, integrates the fingerprint image collector into the display screen, and can realize "Full Screen multi-point" fingerprint identification on the full screen, which has a larger screen identification area than off screen fingerprint products.
Integration and multipoint recognition become the direction of attack"The future development direction of on-screen multi-point fingerprint solution must be high integration, full screen fingerprint multi-point identification and high screen proportion." Wu Zhen, director of marketing department of Tianma Microelectronics Co., Ltd., said in an interview with China Electronics News.
Specifically, the first is high integration. It is mainly to realize the three in one of touch, display and fingerprint identification. It is necessary to break through the limitation that the optical fingerprint in the LCD screen is difficult to match the thickness of the normal cover plate, so as to have more market competitiveness and mass production; At the same time, because the optical path modulation unit is integrated in the display screen, the thickness of the display screen is reduced by more than 50% compared with the external collimating optical path design scheme, making the design of terminal products lighter and thinner. The second is full screen fingerprint multipoint identification. To support full Screen multi-point fingerprint identification in any display area, it can be applied to full screen blind unlocking, APP encryption unlocking and user-defined fingerprint control to achieve high security and high privacy. The third is the proportion of high screen. The fingerprint identification function is built into the display screen to effectively improve the screen proportion of terminal products and bring users a more ultimate visual experience.
In addition, the development and improvement of fingerprint under (in) LCD screen is inseparable from the dimensions of high brightness, high fingerprint recognition rate and improvement of unlocking experience. High brightness requires the brightness of the module to be more than 450 nits. To ensure that more image details are displayed, it can effectively solve the problem of serious brightness loss and bring a smooth viewing and game experience; The ultra-high fingerprint recognition rate refers to the FRR of 3%, which can reach the OLED level; in terms of unlocking experience, the use of unlocking or consumption functions is more intuitive, avoiding accidental touch, simplifying the buttons of mobile phone accessories and improving the overall beauty.
It is understood that in the process of tackling the key problems of LCD off screen fingerprint technology, TCL Huaxing has solved the problems such as the development of Blu films, the improvement of TPM brightness and the improvement of infrared sensor recognition accuracy through continuous transformation and attempt of LCD backlight. Finally, TCL Huaxing has launched the LCD panel off screen fingerprint that can clearly see the fingerprint image, and realized the rapid identification function of LCD off screen fingerprint.Optimize cost and find the way of differentiated competitionThe advantage of fingerprint in LCD screen is that it can do large-area and multi fingerprint identification, and can improve the diversified space of human-computer interaction experience of intelligent terminal. For example, it can deeply encrypt app, ensure wealth security and improve vehicle driving experience; it can also provide higher-level guarantee for the information security of smart factory, smart city, smart home, smart transportation and intelligent medical treatment.
According to Wu Zhen, in the future, the fingerprint on the LCD screen can encrypt any app. When users click the app icon, they need to complete fingerprint verification before they can further open and run the app. Compared with the encryption method that the existing mobile phone app needs to press the finger at the specified position for fingerprint verification, it is more convenient. The fingerprint on the LCD screen can even realize that when using a joint account on the ATM, two people need to use it at the same time The operation function of transfer can only be realized by inputting fingerprint.
Since the release of full screen optical fingerprint identification LCD screen by Youda optoelectronics, Tianma's latest LCD multi touch in screen fingerprint scheme has met the conditions for mass production, and is sending samples to terminals of world-famous brands. The off screen (in) fingerprint scheme has been launched for a long time, but it has not been commercialized on a large scale. What step has the overall off screen fingerprint taken in the process of mass production application?Liu Yushi, senior analyst of cinno research, said in an interview that the under screen (inner) fingerprint of LCD has been opened up technically. Compared with the rigid OLED with optical under screen fingerprint, it has no advantage in mass production cost, so there is little practical application at present. At present, the under screen (inner) fingerprint of LCD is actively optimizing the cost and looking for a way to compete with the off screen fingerprint of OLED.Xu Jingjing, senior analyst of semiconductor device research at sigaintell, said in an interview with China Electronics News that the fingerprint scheme under the LCD screen (inside) is still in the research and development stage. From the perspective of application field, compared with mobile phone terminals, it is expected to be promoted in the vehicle display and door lock Market in the future, and mass production is expected to be realized in the second half of 2021.
One of the evolution trends of touch display is to help the touch display module continuously add value by adding more functions from the device structure level. Although the latest LCD on-screen fingerprint solution still has some details to be optimized, the release of this technology has revived the confidence of practitioners in LCD fingerprint solution.