We have taken huge steps in improving the design, size, and material of our sensors, and this has led to many new ways of placing them in a device. Power consumption in our solutions is down to almost nothing, and with our FPC OneTouch® technology the sensor is always ready for human interaction.
Fingerprints offers a complete range of technology for working with fingerprint biometrics that can be used separately or in combination, including sensors, biometric processors, and modules. The competitive advantages offered by Fingerprints’ technology include unique image quality, extreme robustness, low power consumption, and complete biometric systems.
Fingerprints’ area sensor and swipe sensor are both based on patented proprietary technology, which offers several strong advantages such as high image quality, programmable pixel elements, and 256 gray-scale values from every single pixel element. The sensors contain small capacitive plates, each with their own electrical circuit embedded in the chip. The sensors use Fingerprints’ proprietary HSPA (High Sensitive Pixel Amplifier) that allows each pixel element in the sensor to detect very weak signals, which improves image quality for all types of fingers.
Extremely weak electrical charges, sent via the finger, are created, building a pattern between the finger’s ridges or valleys and the sensor’s plates. Using these charges, the sensor measures the capacitance pattern across the surface.
Fingerprints’ HSPA method also allows the use of a patented protective coating that is 25 to 30 times thicker than other suppliers and helps Fingerprints’ sensors to withstand values well above the European Community Standard Class 4 requirement of 15 kV for static electricity (ESD) and to withstand wear and tear.
Capacitance is the ability to hold an electrical charge. Fingerprints’ sensors contain tens of thousands of small capacitive plates, each with their own electrical circuit embedded in the chip. When the finger is placed on the sensor, extremely weak electrical charges are created, building a pattern between the finger’s ridges or valleys and the sensor’s plates. Using these charges, the sensor measures the capacitance pattern across the surface. The measured values are digitized by the sensor and sent to the neighboring microprocessor.
The surface of a capacitive sensor is a neat array of plates that are able to measure the capacitance between these plates and thus the fingerprint contour. This can be done directly by applying an electrical charge to the plate.
The latter method is called the active measurement method, sometimes referred to as reflective or inductive capacitive measurement, and it brings several advantages. The programmable logic internal to the capacitive sensor configuration makes it possible to read off and adjust the sensor reception to different skin types and conditions. Another important benefit is that the strengthened signal between the fingerprint surface and the sensor plates allows for the introduction of a strong, protective coating layer – up to 25-30 times thicker than other suppliers – on the sensor surface. This enables Fingerprints, as one of the very few sensor vendors, to produce devices that withstand values well above the requirement for 15 kV electrostatic discharge (ESD) and that withstand wear cycle tests of more than one million touches to the sensor.