Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > EDA/IP

Biometric sensors add a glamorous touch

Posted: 21 Oct 2002 ?? ?Print Version ?Bookmark and Share

Keywords:Loreal? STMicroelectronics? biometrics technology? SkinChip? silicon fingerprint sensors?

Cosmetics maker L'Oral and chipmaker STMicroelectronics have announced a joint development agreement that brings biometrics technology to the skin-care business.

The companies rolled out the SkinChip, a rectangular piece of silicon that enables beauty-conscious users to check the moisture content of their skin. L'Oral said it plans to deploy the device at department store cosmetics counters to help customers select the right moisturizers for their skin type.

The product layers on yet another opportunity for the multibillion-dollar cosmetics industry and again shows that technology devised for fingerprint recognition may prove applicable to a host of untapped markets. In the past year, makers of biometric fingerprint recognition systems have said that they are working on applying the technology to safes, cellphones, drivers' licenses, frequent-flier cards, automotive ignition systems, and even handguns.

In the next five years or so, this is going to become a very big market," said Naeem Zafar, CEO at Veridicom Inc., which makes silicon fingerprint sensors that compete with those of STMicroelectronics. "Ultimately, fingerprint sensors are going to become ubiquitous household devices, and the market for them will grow to anywhere from $2 billion to $10 billion a year."

Fingerprint foundation

STMicroelectronics engineers said that L'Oral approached them approximately two years ago with the idea for the SkinChip.

"They told us they had seen new fingerprint sensors in very compact form factors and said that had triggered an unusual idea," said Alan Kramer, director of STMicroelectronics' Touch Chip Business Unit.

Indeed, L'Oral's idea was to place a touch chip in a wandlike device that could be pressed against a person's face to measure the moisture content of his or her skin. The companies spent the last two years developing the hardware and software for the application.

L'Oral said it intends to use the technology at cosmetics counters, to help customers choose the right grade of moisturizer for their skin. The company's researchers also want to use it internally, to help develop new cosmetic compounds.

The system's software, which will reside in a laptop PC, is endowed with image-processing algorithms that enable it to find wrinkles and measure the hydrophobicity, or moisture content, of the skin. By knowing the moisture content, L'Oral said, cosmetics experts can treat wrinkles and apply moisturizer in a way that doesn't leave the skin too dry or too greasy.

The key to L'Oral's system is a penlike wand about the diameter of a quarter. The wand, which links to a laptop PC via a cable, employs the SkinChip, which is based on STMicroelectronics' TouchChip technology.

The TouchChip, originally developed for fingerprint recognition applications, is important for L'Oral's system because it reportedly offers greater sensitivity to detail than conventional fingerprint recognition technologies. The silicon chip, which measures 13-by-18mm, contains an array of 256-by-360 pixels. The pixels, each measuring 50-by-505, contain two side-by-side capacitor plates with an amplifier and a so-called "fringing field."

Together, the amplifier and the fringing field create an active charge-to-voltage conversion circuit that enables the chip to make capacitive measurements, but in a way that differs from conventional capacitive techniques. Unlike conventional techniques, the TouchChip's capacitive measurements are made as a function of interference. As a result, when an object comes close to the silicon, it interferes with the fringing field lines and reduces the capacitance. So, unlike conventional techniques, capacitance decreases when skin is near the silicon and increases when skin is farther away.

"Using that method, we get a much better signal-to-noise ratio, which means we are able to measure distances to a greater level of detail," Kramer said.

For the L'Oral application, that sensitivity is said to be key because it is linked to conductance, which translates to an ability to measure moisture.

In addition to the TouchChip sensor, STMicroelectronics' solution includes an A/D converter, which translates the analog signal from the chip to a digital signal. It also incorporates an analog conditioning stage, control logic, and an 8-bit microcontroller that does USB conversion.

The entire solution costs in the "low-$30 range," while the capacitive TouchChip sensor by itself runs in the $20 range, STMicroelectronics engineers said.

Application base growing

Solutions like the one used by L'Oral are reaching a growing number of applications. STMicroelectronics said that it has shipped more than 250,000 fingerprint sensors, with approximately 50,000 of those going into notebook computers as a means of preventing unauthorized people from booting up the devices and looking at their hard drives. The company said its sensors are incorporated in Samsung's GT9000 Series laptops and in other notebook computers.

Makers of fingerprint technology also said their sensors are being employed in a variety of other applications, including national identification cards, government cards and corporate access systems, as well as in proposed frequent flyer cards, which were pitched last year as a means of tightening airport security. Sensor manufacturers even said that the technology is being implemented in smart locks on handguns that prevent children from gaining access to firearms, as well as in future cell phones.

Authentec Inc. said that it has already talked with four unnamed cellphone makers to develop its ultra-small (6.5-by-6.5mm) biometric fingerprint sensor for use with upcoming 3G cellphones.

"A lot of companies are talking to us about integrating our technology into the wireless area," said Steve Mansfield, vice president of marketing for Authentec. "But if you are coming into the market with a high-data-rate phone that offers e-mail and serious corporate network access, you might want fingerprint technology to keep it secure."

Mansfield said that the company has two design wins with cellphone makers and is currently working with "three or four" service providers on providing biometric access techniques.

"People know that cellphones are lost and left in places where anyone could gain access," Mansfield said. "And with cellphones now having access to some very important data, security is becoming a bigger issue."

Authentec is also working with Delphi Automotive Systems on a dashboard sensor that would prevent unauthorized drivers from starting a vehicle. While such systems would still use a key to unlock the steering column, they would also examine fingerprint sensor data before enabling the ignition switch.

Industry members said, however, that biometric sensors need to come down in cost before they become common household items. Zafar of Veridicom said that the market is currently at a $100 million to $200 million per year level, and is growing at a rate of 50 percent to 60 percent yearly, but will dramatically jump in size when the devices reach the common household product stage.

"The market will take off sometime in the next three to eight years," Zafar said. "But these devices have to be ubiquitous for that to happen. And to be ubiquitous in your PC, the sensors need to come down to the $15 level. And to be ubiquitous in cellphones, they are going to have to reach the $5 level."

- Charles J. Murray

EE Times

Article Comments - Biometric sensors add a glamorous to...
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top