JDI's Finger Sensor: Too Little Too Late?

　　In search of a new market beyond smartphones, Japan Display Inc. (JDI) unveiled a transparent glass-based capacitive fingerprint sensor.

　　For JDI, a Sony-Toshiba-Hitachi collaboration that has been mired in the red, sensors represent a whole new market. Although its TFT-based fingerprint sensors have certain advantages over silicon-based solutions, JDI might be arriving too late with too little, observed industry analysts.

　　Katsuhisa Yuda, executive officer and president of JDI's Display Solutions Company, explained during a media briefing here that the new sensors were developed as an extension of the company’s LCD module, known as in-cell Pixel Eyes.

　　With Pixel Eyes, JDI had already integrated a basic touch function into the glass substrate of the TFT display. Pixel Eyes eliminates the need to add an external touch-panel module.

　　But with the new technology, “We have gone a step further,” explained Yuda. The glass substrate can now not only identify where a finger touches, but also "read" the changes in capacitance caused by the recesses and ridges of an individual fingerprints.

　　The end result is a capacitive fingerprint sensor on a pane of glass. JDI is hopeful that the high transparency of the glass substrate will open the door to a broad range of new applications not possible on widely available silicon-based fingerprint sensors. The goal is to go beyond smartphone displays to credit cards, door locks and elsewhere. “We can combine it with a backlight, or use it on a flexible surface,” Yuda said.

　　There are two approaches to TFT-based circuitry for fingerprint solutions. The first replaces the silicon but still offers a stand-alone fingerprint module. The other integrates sensor circuitry into the display’s TFT backplane for an in-display solution. What JDI is offering here is the former. The company provides a sensor module with an effective sensor measuring 8.0mm x 8.0mm. With 508 dpi pixel density, it offers 256 gradation and 160 x 160 resolution.

　　The winter for fingerprint sensor suppliers?

　　Had this innovation come a year ago, when the industry was worried about the emerging trend of removing the home button from smartphones, this might be a different story. Then, OEMs, controller IC makers and panel makers were frantic for display-based fingerprint sensors with a variable sensing area for greater flexibility, as well as multi-finger input assigned through the OS for more convenience.

　　IHS Markit then argued the advantages of display-based fingerprint sensors as being “invisible and not affecting the appearance of the set.” The firm also argued that display-based sensors might be cheaper than their silicon-based counterparts.

　　A year later, though, the market research firm’s latest “Fingerprint Sensors Overview Report," issued earlier this month, introduces a fresh plot twist.

　　Jamie Fox, principal analyst for LEDs and lighting at IHS Markit, wrote: “The fingerprint sensors market is facing a major disruption following the introduction of Face ID, a facial recognition system designed and developed by Apple Inc. for its iPhone X, along with the forthcoming arrival of in-display sensors and Chinese vendors winning market share from Western vendors.”

　　He noted, “Overall, Apple’s decision to replace Touch ID with Face ID will lead to 1.1 billion fewer fingerprint sensors produced by the end of 2021 than if Apple had maintained Touch ID in iPhones.”

　　During the press briefing, Yuda was asked if JDI plans to test the smartphone market with its new fingerprint sensor. He said JDI is “undecided,” an indication of its reluctance to engage an already brutally price-competitive market.

　　The lay of the lan

　　Calvin Hsieh, director of touch and user interface at IHS Markit, doesn’t believe JDI has much chance in the smartphone fingerprint market. He told EE Times this week, “JDI cannot get into the smartphone fingerprint sensor market, because of the falling ASP (average selling price) trend.”

　　He explained that silicon- and display-based fingerprint solutions are positioned differently. With silicon, he said that capacitive type is mainstream, mostly made of silicon and mature for all product segments. Its ASP is $1.20 to 3.

　　In the display-based segment, he noted, “So far, CIS under-display solution is mainstream, only for AMOLED (cannot be applied to LCD), and high-level. Its ASP is $10-$12.”

　　Qualcomm Sense ID — ultrasonic fingerprint solution — is display-based, he said, but won’t be ready until the end of the first quarter this year. Hsieh said its ASP is not yet known. “Its advantage [over CIS] is live-body detection,” he added.

　　In short, with or without JDI’s glass-based capacitive sensor, the smartphone market has enough related technologies.

　　Silicon-based vs. TFT-based

　　So, what are the pros and cons of silicon-based vs. TF-based fingerprint solutions?

　　TFT-based (on glass or plastic) solutions — JDI’s fingerprint sensor among them — “can make use of lower-cost TFT process,” Hsieh said. “It also can digest panel markets’ smaller gen sized fabs.” He added, “To lower ASP, IC maker is the key — 508 ppi (no display circuits) is not difficult to panel makers but they need read-out IC.”

　　Silicon-based solutions are “very mature and affordable now,” Hsieh said.

　　Hsieh’s bottom line is that TFT-based fingerprint sensor is “one year late to enter the smartphone market.” For JDI, commercial (highlighting low cost and flexible endurance) market is the way to go, he concluded.

　　JDI’s Yuda believes that in the growing world of the Internet of Things (IoT), high security devices are paramount. “Individual certification systems also require even higher security systems, and use fingerprint sensors,” he predicted. “Transparent fingerprint sensors should improve the degrees of design freedom to enable such sensors to be installed in nearly every device to make security enhancement much easier.”

　　Yuda predicts that TFT-based fingerprint solutions will replace silicon. Silicon, he noted is brittle. “It can break.” Hsieh agreed. “If it can be TFT-based and flexible, endurance can be the winning factor,” he said.

　　JDI will start commercial shipments of its new fingerprint sensors during its 2018 fiscal year, which ends in March of 2019.

　　JDI’s non-smartphone business

　　Yuda became the head of JDI’s Display Solutions Company last fall. His charter is to cultivate new markets other than smartphones. “Although my company has ‘display’ in its name, our business is not constrained to displays,” he said.

　　Among Display Solutions Company’s product portfolio, existing products are screens for high-end digital cameras, reflective LCDs for wearable devices and displays for VR headsets and high-end notebook PCs. By fiscal 2020, the goal for Yuda’s group is to generate revenue of 100 billion yen. The group is already halfway there based on current product lines, according to Yuda. A range of products currently gestating at JDI’s Display Solutions Company include fingerprint sensors and reflective displays for in-store tags — designed under a partnership with E-Ink.

　　JDI’s current financial woes stem largely from its late entry into OLED technology. JDI, whose business was traditionally dependent on Apple’s iPhones, suffered a hit from Apple’s recent decision to switch to OLED panels for iPhone X.

　　JDI will begin making smartphone OLED panels in 2019. However, by then, several rivals who began OLED investment earlier are widely expected to have started production.