Fingerprint Identification Voltage Dividing Unit Resists Ambient Light
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current optical fingerprint identification devices face difficulties in extracting weak fingerprint signals due to ambient light interference, making fingerprint identification challenging.
Innovation Solution
A fingerprint identification device with a voltage dividing unit comprising a pressure sensitive member and an equivalent resistor, connected in series, is used to control a thin film transistor, ensuring it remains in an OFF state unless pressed, thereby resisting ambient light interference and allowing for effective fingerprint signal detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If an optical fingerprint identification device is used, then fingerprint identification can be performed, but ambient light interference makes it difficult to extract weak fingerprint signals
Solution Approach 1:
The patent extracts and separates the control function from the detection function by introducing a pressure-sensitive member that independently controls the thin film transistor state. This allows the detection system to ignore ambient light when the transistor is OFF and only process signals when pressure is applied, effectively extracting the fingerprint signal from the ambient light interference.
Solution Approach 2:
The patent applies preliminary anti-action by using the pressure-sensitive member to preemptively control the thin film transistor to remain in an OFF state before fingerprint detection. This preliminary control action prevents ambient light from generating false signals in the first place, rather than trying to filter or remove interference after it has affected the detection.
2Measurement precision
If the thin film transistor is kept in OFF state to resist ambient light interference, then fingerprint signal detection is improved, but the device cannot detect signals when not pressed
Solution Approach 1:
The patent applies dynamics by making the thin film transistor state changeable based on pressure input. The transistor dynamically switches between OFF state (when no pressure is applied, resisting ambient light interference) and ON state (when pressure is applied, enabling fingerprint signal detection). This dynamic adaptation allows the device to optimize its detection capability for different operational conditions.
Solution Approach 2:
The pressure-sensitive member acts as an intermediary that mediates between the ambient light environment and the detection system. It controls the thin film transistor state based on pressure input, allowing the system to adapt to different conditions - blocking ambient light interference when idle and enabling signal detection when a fingerprint is pressed.
3Measurement precision
If a voltage dividing unit with pressure sensitive member is added, then ambient light interference is reduced and fingerprint detection is improved, but device complexity increases
Solution Approach 1:
The patent applies multi-functionality by designing the voltage dividing unit where the pressure-sensitive member serves multiple purposes: it controls the thin film transistor state to resist ambient light interference, enables fingerprint signal detection when pressed, and provides pressure information for additional verification. This single component performs multiple functions that would otherwise require separate systems.
Solution Approach 2:
The patent merges the control function and detection function into a single integrated circuit structure. The voltage dividing unit combines the pressure-sensitive member with the thin film transistor control, allowing one component to simultaneously manage both the resistance to ambient light interference and the enabling of fingerprint signal detection, thereby reducing overall device complexity despite the added functionality.
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
This solution enhances fingerprint identification accuracy by preventing ambient light interference and allowing for precise detection of fingerprint signals, even under intense light conditions, while also providing pressure information for additional user experience and safety features.
Implementation Method 1
the voltage dividing unit includes a pressure sensitive member and an equivalent resistor connected in series
Implementation Method 2
a photosensitive member and a thin film transistor; the first gate line is connected with the voltage dividing unit, the voltage dividing unit includes a pressure sensitive member and an equivalent resistor connected in series
Data Source
Figure 1
Figure 2~3
Figure 4~6
AI summary
Embodiments of the present disclosure provide a fingerprint identification device, an array substrate, a display device and a fingerprint identification method. The fingerprint identification device includes: a first gate line (Gate1, Gate2, Gate3), a second gate line (Gate'1,Gate'2,Gate'3), a read signal line (S1,S2,S3,S4,S5,S6,S7)and a voltage dividing unit, wherein, a plurality of fingerprint identification units (A) are defined by the second gate line (Gate'1,Gate'2,Gate'3) and the read signal line(S1,S2,S3,S4,S5,S6,S7) intersecting with each other, and the fingerprint identification unit (A) includes a photosensitive member (VD) and a thin film transistor (T); the first gate line (Gate1, Gate2, Gate3) is connected with the voltage dividing unit, the voltage dividing unit includes a pressure sensitive member and an equivalent resistor connected in series, and the second gate line (Gate'1,Gate'2,Gate'3) is connected between the pressure sensitive member and the equivalent resistor. The pressure sensitive member and the equivalent resistor are connected in series to form the voltage dividing unit, so that a switching signal which originally controls the fingerprint identification unit is subjected to voltage division by the voltage dividing unit and then is applied to the gate electrode of the thin film transistor, to change the ON-OFF state of the thin film transistor with a change in a finger pressure, which may resist interference of stray light in the environment, and reduce difficulty in fingerprint identification; and at a same time, pressure information of the finger may be obtained, which may be used as auxiliary information for safety identification, to achieve richer user experience.