Gate Pulse Modulation Circuit for LCD Sub-Pixel Charging Uniformity
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Solution Overview
Problem
Existing liquid crystal display (LCD) devices with half source driver designs face issues of non-uniform charging of sub-pixels, leading to dark-bright lines and flicker phenomena, which compromise display quality due to inadequate gate pulse modulation circuits.
Innovation Solution
A gate pulse modulation (GPM) circuit is introduced, comprising a low dropout regulator, resistors, capacitors, switches, a comparator, logic control unit, and level shifter, which generates modulated clock signals with controlled falling slopes to ensure uniform charging of pixel elements, minimizing dark-bright lines and flicker.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a half source driver (HSD) design is used to reduce power consumption, then power consumption is reduced, but non-uniform charging of sub-pixels occurs leading to dark-bright lines and flicker phenomena
Solution Approach 1:
The patent applies periodic action by introducing modulated gate pulses with different widths for odd and even sub-pixels. The gate pulse width is periodically varied based on the sub-pixel type, creating a rhythmic charging pattern that compensates for the non-uniform charging inherent in HSD design. This periodic modulation ensures that both odd and even sub-pixels receive appropriate charging durations, eliminating dark-bright lines while maintaining the power savings of HSD architecture.
Solution Approach 2:
The patent implements local quality by applying different gate pulse widths to different sub-pixel groups. Specifically, odd sub-pixels receive gate pulses with one width while even sub-pixels receive gate pulses with a different width. This localized differentiation addresses the specific charging needs of each sub-pixel group, ensuring uniform display quality across the entire screen while preserving the overall power consumption benefits of the HSD design.
2Device complexity
If conventional gate pulse signals are used in HSD design, then circuit complexity is reduced, but non-uniform charging occurs causing display defects
Solution Approach 1:
The patent applies dynamics by making the gate pulse width variable rather than fixed. The gate driving circuit dynamically adjusts the pulse width based on the sub-pixel type (odd or even), creating a flexible charging mechanism. This dynamic adaptation allows the circuit to compensate for charging non-uniformity without requiring a complete redesign of the HSD architecture, thus improving charging uniformity while maintaining relatively simple circuit implementation.
3Reliability
If uniform charging of sub-pixels is achieved through gate pulse modulation, then display quality is improved, but additional circuit components are required
Solution Approach 1:
The patent implements merging by integrating the gate pulse modulation function directly into the existing gate driving circuit of the HSD design. Rather than adding separate modulation circuits for each sub-pixel, the invention combines the modulation capability with the gate driver itself, using shared components and a unified control approach. This integration achieves uniform sub-pixel charging while minimizing the increase in overall circuit complexity.
Data Source
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AI summary
The present invention relates to a gate pulse modulation (GPM) circuit and the application of same in a liquid crystal display for improving the display performance thereof. The gate pulse modulation circuit is configured to modulate multi-phase clock pulse signals so as to correspondingly generate odd gate pulse waveforms and even gate pulse waveforms that are different from one another.