Fingerprint Recognition under Optical Screen: Fully Manual Solution for the Full-screen Concept

Once the full-screen concept was introduced, it quickly occupied the mobile phone market. At present, the traditional ‘HOME’ key capacitive fingerprint unlocking is a rare design for new mobile phones. The full screen provides a more complete vision, which enhances the appearance of the phone. At the same time, a larger screen provides more scientific and reasonable split of the screen, bringing a better experience. The reason for the popularity of full-screen concept is that the demand of users has suggested the research and production direction for mobile phone manufacturers.

 

Full-screen concept spawns fingerprint unlocking scheme under screen

The full screen is the display area on the front side, and there are three solutions to unlock the mobile phone without using ‘HOME’ key: face recognition, backside fingerprint unlocking and under-screen fingerprint unlocking.

In these three schemes, the backside recognition will influence the beauty of backside, and it is not a comfortable unlocking way for those ‘HOME’ key unlocking scheme users. Based on these reasons, it is expected to be used only by low-end mobile phones and may be gradually eliminated.

About face recognition, users need to consider about many things like light, holding angle and occlusion. Since the technology of face recognition still needs development, it is not convenient enough to use it now.

As for the under-screen fingerprint unlocking scheme, it can cancel the ‘HOME' button and conform to the user's operating habits, so under-screen fingerprint unlocking scheme is expected to become the mainstream solution for the current full-screen mobiles.

The full-screen mobile phone was first launched by Sharp in 2013, but it was not until the emergence of Xiaomi MIX in 2016 that the full-screen was noticed by most consumers. Although being popular among consumers, this phone is not actually mass-produced. However, the full screen has become an important selling point in the mobile phone industry, and Vivo X20Plus released in 2018 is the first mass produced mobile phone equipped with the under-screen fingerprint unlocking scheme.

 

Optical scheme is the mainstream choice for fingerprint recognition under the screen

Among the three schemes for implementing the fingerprint recognition under the screen, the ultrasonic performances best. However, the ultrasonic penetration is insufficient and can only be applied to flexible OLED screens. And each flexible OLED screen is 60 USD more than the average hard screen, making the ultrasonic solution difficult to become the mainstream choice in the future, and it is expected to be applied only on some high-end full-screen smart phones.

 

As for the glass-based capacitor scheme, it has insurmountable difficulties in the actual use. Glass-based capacitor scheme is predicted to only be applied to the low-end LCD full-screen mobile phone in the future.

The optical solution is based on the optical system. Although it has a slight deficiency in unlocking speed, power consumption and anti-interference ability, its industrial chain is more mature than the other two for its long application. In addition, due to the higher economic benefits of mass production, major manufacturers already have solutions for those slight deficiency. It is expected that the optical solution will become the main solution for under-screen fingerprint in the future.

 

Optical solution industry chain

Since the mass production of under-screen fingerprint unlocking mobile phone in 2018, the market penetration of it has become higher and higher. It is estimated that the shipment of under-screen fingerprint unlocking mobile phones will reach 200 million sets in 2019, which is about 6 times that of 2018.

 

Principle of fingerprint recognition under optical screen

 

According to the principle of fingerprint recognition under the optical screen, the important components of the whole identification module are algorithm chip, filter and sensor, and the most technologically advanced one are algorithm chip. The leading manufacturers of it are the US Synopsys and China's Goodix.

Industry chain and leading enterprises

According to several under-screen fingerprint unlocking mobile phones released this year, the price of the fingerprint module under the screen is constantly falling. In March of this year, vivo released X21, and its fingerprint solution was supplied by Synopsys and Goodix. At that time, the cost of the fingerprint module under the screen was about 15 US dollars; while the Meizu released 16th, its fingerprint chip was provided by Synopsys, and the price is around $17.

However, when OPPO released its R17 series, the fingerprint module cost has been reduced to 8-9 US dollars; and the X23 of Vivo which released in September, its fingerprint model has also dropped to 8-9 dollars.

The price falling will be a serious blow to fingerprint module manufacturers, especially in the follow-up market. Because with the vicious competition going on, the price may be as low as 2 US dollars. However, this has less impact on the companies that provide solutions, like Synopsys and Goodix.

 

Goodix

Based in Shenzhen, China, Goodix is a solution provider on chip design and software development.

It currently provides semiconductor hardware and software solutions for smart terminals, Internet of Things and automotive electronics. Goodix's products and solutions have been widely used in Huawei, OPPO, vivo, Xiaomi, Google, Amazon, Samsung, Nokia, Dell, HP, LG, ASUS and other international famous brands. And as a biometric solution provider, its products are most widely used in the Android camp.

Most mobile enterprises cooperate with GOODIX

 

Since 2019, dozens of mobile phones have been released by various brands. Most of the flagship models use optical fingerprinting solutions. Goodix has a monopoly advantage among China’s mobile phone manufacturers, and the most iconic event of the year was its cooperation with Huawei. The newly released 5G mobile phone – Huawei Mate20 X 5G was designed with the contribution of Goodix, because the latter provides the innovative fingerprint and touch solutions.

Since the under-screen fingerprint recognition mobile phone became a hot sale, the total revenue of Goodix has kept rising in 2018. However, in 2019, Goodix's revenue and gross margin both experienced negative growths.

GOODIX experienced a decrease in 2019Q1

Part of the reason is another bio-unlocking solution, that is, the more automated face unlocking scheme is constantly improving with the advancement of technology. If the delay of face recognition technology is improved, and the cost of it can be reduced by mass production, the market share of the under-screen fingerprint unlocking scheme will be greatly reduced.

Another reason is the development of under-screen ultrasound fingerprint unlocking scheme. This solution is better than the fingerprint unlocking scheme under the optical screen, and Samsung is equipped with an ultrasonic unlocking scheme. If the flagship products of the mobile phone brands all tend to apply ultrasonic solution, it is expected that the market share of the fingerprint unlocking scheme under the optical screen will drop significantly. At that time, if Goodix has no optical solution that can match the use of the ultrasonic solution nor ultrasonic solution, the company's position in the market will be shaken.

Compared with the last quarter of 2018, the research and development expense of Goodix decreased by 35.6% in the first quarter of 2019. And the decrease of R&D expense is a dangerous signal in the ever-changing technology industry.

R&D expense only takes 25.4% of 2019Q1’ costs