How does double-click wake-up work on smartphones?

There are many ways to wake up the screen, and the most common way is to press the power button to light up the screen. However, as mobile phone screens become larger and larger, the position of the power button is becoming more and more difficult to touch due to the size of the phone and the feel of the hand. Therefore, new unlocking methods such as double-clicking the screen to unlock, unlocking with a watch or bracelet, unlocking with fingerprints, and NFC have emerged.

However, due to various hardware and external conditions, fingerprint unlocking and bracelet unlocking are not convenient for the phone itself, and require a built-in fingerprint recognition module or the help of external devices to unlock. Therefore, double-clicking to unlock and wake up the screen has become one of the most convenient and lowest-cost unlocking methods on smartphones.

LG is one of the first Android phones to support double-click wake-up. The double-click wake-up on the LG G2 is very convenient, sensitive and accurate. With the development of LG G3, LG has launched a unique KnockCode unlocking, which has taken the security and experience of knocking to unlocking to a higher level.

HTC One M8 also supports double-click wake-up, and also supports wake-up by sliding when the screen is dark, which is very convenient for entering specific application programs.

The newly released Nexus 9 also supports double-click wake-up, and Nexus 6 will also have this feature in the future. This shows that double-click wake-up has been adopted by Google and integrated into the Android system.

In addition, some domestic mobile phone manufacturers' Android phones also support double-click wake-up, such as Huawei's Honor 3C series, OPPO Find series, Nubia phones, Meizu MX4, etc.

In fact, the double-click wake-up function was first used by Nokia, and was later adopted by various mobile phone manufacturers. The principle of double-click wake-up is very simple. In fact, the display screen and touch screen of the mobile phone are actually two separate components, but the touch screen is almost transparent and cannot be seen by users when it is attached to the display screen. The touch screen recognizes the gesture signal and transmits it to the processor, and the display screen is only responsible for displaying the corresponding image.

When the display of a traditional mobile phone is turned off, the touch screen is also turned off, and neither of them works. Mobile phones with wake-up functions, such as LG G3 and HTC One M8, turn off the display, but the touch screen is still powered on. Users can slide and input at any time in the black screen state. When you make a specific gesture, it is equivalent to giving a signal of a power button. After the processor recognizes it, the screen turns on and double-click wake-up is realized.

As a winner of Toutiao's Qingyun Plan and Baijiahao's Bai+ Plan, the 2019 Baidu Digital Author of the Year, the Baijiahao's Most Popular Author in the Technology Field, the 2019 Sogou Technology and Culture Author, and the 2021 Baijiahao Quarterly Influential Creator, he has won many awards, including the 2013 Sohu Best Industry Media Person, the 2015 China New Media Entrepreneurship Competition Beijing Third Place, the 2015 Guangmang Experience Award, the 2015 China New Media Entrepreneurship Competition Finals Third Place, and the 2018 Baidu Dynamic Annual Powerful Celebrity.