Inkjet Printhead Element Substrate Voltage Drop Compensation

The patent applies local quality by making transistor sizes non-uniform across the element substrate. Specifically, transistors are designed with different sizes depending on their position: those closer to the power supply electrode pad have smaller sizes, while those farther away have larger sizes to compensate for higher wiring resistance. This localized variation in transistor dimensions ensures that each print element receives an appropriate drive current despite position-dependent resistance differences, thereby maintaining consistent discharge characteristics across the staggered arrangement of element substrates.

The patent implements local quality by varying transistor sizes only in the direction along the power supply wiring, rather than uniformly increasing all transistor sizes. This selective sizing approach compensates for wiring resistance differences while minimizing the overall substrate area increase. The transistor size gradient is optimized to achieve voltage equalization with minimal area penalty.

The patent applies universality by designing a standardized element substrate structure that can be repeatedly arranged in staggered patterns to form full-line printheads. The power supply wiring and transistor sizing scheme is designed to work consistently across multiple substrates, allowing the same design principles to be applied universally regardless of the number of substrates used. This modular approach simplifies the overall wiring complexity while maintaining high printing speed capability.