Electro-Optical Device Driving Circuit for Signal Voltage Accuracy
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electro-optical devices using OLEDs, signal voltages written to data lines can deviate from desired values due to capacitive coupling with adjacent lines, leading to non-uniform luminance and potential changes.
Innovation Solution
The electro-optical device includes a driving circuit that operates in selection and writing periods to control data potentials and set currents, ensuring accurate data potential writing and mobility compensation across pixel circuits, thereby minimizing potential deviations and ensuring consistent luminance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If signal voltages are sequentially supplied to multiple data lines in a multiplexer driving scheme, then the writing speed and productivity are improved, but capacitive coupling between adjacent data lines causes signal voltage deviation and reduces manufacturing precision
Solution Approach 1:
A selection transistor is introduced as an intermediary component between the data line and the pixel circuit. This transistor acts as a switch that isolates the data line from the pixel circuit during the writing process, preventing capacitive coupling effects from adjacent data lines while enabling sequential writing to multiple data lines. The selection transistor is turned on only when writing to its corresponding data line, thereby maintaining signal voltage accuracy while preserving high writing speed.
2Manufacturing precision
If the selection transistor is kept in the off state before the signal writing period, then the signal voltage accuracy is improved by preventing capacitive coupling, but the adjustment time for gate-source voltage increases
Solution Approach 1:
The selection transistor is pre-configured in the off state before the signal writing period begins, which preliminarily prevents capacitive coupling effects. This preliminary action ensures that when signal voltages are sequentially written to multiple data lines, adjacent data lines remain isolated and do not cause potential deviations. The transistor is then activated only when needed for the specific writing operation, minimizing the overall adjustment time while maintaining signal voltage accuracy.
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 approach effectively suppresses potential deviations and ensures consistent data potential writing, improving luminance uniformity and reducing the time required for gate-source voltage adjustment, leading to enhanced display performance.
Implementation Method 1
a light emitting element (E) that emits light with luminance in accordance with the written data potential
Implementation Method 2
a parasitic capacitance is present between the adjacent data lines, so that capacitive coupling is performed therebetween
Data Source
AI summary
An electro-optical device includes a first pixel circuit which is disposed so as to correspond to each intersection between a scanning line and a first data line, a second pixel circuit which is disposed so as to correspond to each intersection between a scanning line and a second data line, a signal line, a selection section, a driving circuit. In a first selection period, the selection section is operated such that the first data line and the second data line are electrically connected to the signal line. In the second selection period, the selection section is operated such that the second data line is electrically connected to the signal line. In a writing period, the first data potential is supplied to the first pixel circuit and the second data potential is supplied to the second pixel circuit.