Under-Display Fingerprint Sensing With Air-Gap Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electronic devices with fingerprint verification functions face difficulties in accurate fingerprint authentication due to the placement of fingerprint sensors at the device's lower end or rear surface, making it challenging for users to position their fingers correctly while gripping the device, leading to errors in the authentication process.
Innovation Solution
An electronic device design featuring a fingerprint sensor integrated under the display, utilizing light radiated from the display pixels to capture fingerprint images, with a processor controlling the sensor and a printed circuit board for electronic connection, allowing for accurate fingerprint recognition without the need for specific finger placement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the fingerprint sensor is disposed at a lower end or rear surface of the case, then the device structure is simple and manufacturing is easier, but the user must position the finger at a specified point which is difficult to achieve while gripping the device, leading to authentication errors
Solution Approach 1:
The fingerprint sensor is moved from the traditional peripheral location (lower end or rear surface) to a new spatial dimension - integrated within the display area itself. This dimensional relocation allows the sensor to be positioned at multiple locations across the display surface, enabling users to place their fingers naturally while gripping the device without requiring precise positioning at a single specified point.
Solution Approach 2:
The display area serves dual functions: it displays visual information and simultaneously houses the fingerprint sensor for authentication. This multi-functionality allows the same surface area to provide both user interface and biometric verification capabilities, eliminating the need for separate dedicated sensor locations that require precise finger placement.
2Device complexity
If the fingerprint sensor is disposed at a lower end of the case, then the device structure is simplified, but it is difficult for the user to position a finger at a specified point while continuing to grip the electronic device
Solution Approach 1:
The fingerprint sensor is merged with the display structure, combining two previously separate components (display and authentication sensor) into a single integrated unit. This merging eliminates the need for separate sensor housings and complex mounting structures at the device periphery, simplifying overall device complexity while enabling natural finger placement across the display surface during normal gripping operations.
3Area of stationary object
If the fingerprint sensor is disposed on a rear surface of the case, then the front display area is maximized, but errors frequently occur in the fingerprint authenticating process because the user must use their senses to position the finger on the sensor
Solution Approach 1:
The sensor is relocated from the rear surface (z-dimension) to the front display area (x-y plane), changing its spatial dimension. This allows the sensor to be positioned within the visible display area where users can naturally place their fingers without relying on tactile sensing or visual alignment, thereby improving authentication accuracy while maintaining maximum display area.
Solution Approach 2:
The display area itself serves the dual purpose of showing information and guiding finger placement for authentication. Users can visually see the display content and simultaneously position their fingers on the appropriate area of the display for fingerprint capture, eliminating the need for separate tactile or visual guidance mechanisms.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enhances the accuracy and ease of fingerprint authentication by allowing the sensor to capture images through the display, reducing errors and improving user experience by eliminating the need for precise finger positioning.
Implementation Method 1
acquire image information to be used for authentication of a fingerprint corresponding to an object that approaches the fingerprint recognition area using, at least partially, light radiated from the display pixel layer and reflected by the object
Data Source
AI summary
An electronic device is provided that includes a display in which a fingerprint recognition area is formed and which includes a display pixel layer, and a rear panel, formed under the display, having a first hole. The electronic device also includes a bracket, disposed under the rear panel, having a sensor accommodating area corresponding to a fingerprint sensor. The electronic device additionally includes the fingerprint sensor disposed under the display pixel layer and adapted to acquire image information to be used for authentication of a fingerprint using at least partially light radiated from the display pixel layer and reflected by the object. The sensor accommodating area has a second hole passing through the bracket, and the fingerprint sensor is disposed in the sensor accommodating area such that an air gap between the display and the fingerprint sensor is formed at least by a portion of the second hole.