Print Element Substrate Layout for End-Area Temperature Detection

Solution Overview

Problem

Existing print element substrates face challenges in accurately detecting temperature distribution and performing high-precision temperature control due to uneven temperature gradients, particularly at the ends and corners, leading to image quality deterioration.

Innovation Solution

The substrate design includes a configuration where temperature detection elements are strategically positioned near the ends and corners, with varying distances from the center, allowing for accurate temperature detection and control across the entire substrate.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If temperature detection elements are arranged at identical positions in all heating areas, then the device structure is simple and easy to manufacture, but temperature distribution at end portions cannot be accurately detected

Engineering Contradiction:

Improveease of manufactureVSAvoidtemperature detection accuracy

Core Design Contradiction:

Ease of manufactureVSMeasurement precision

Solution Approach 1:

The patent applies local quality by varying the position of temperature detection elements according to their location within the print element substrate. Detection elements in end portions are positioned differently from those in central portions, optimizing each location's measurement capability according to its specific thermal characteristics and heat loss patterns.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent implements asymmetry by breaking the uniform arrangement pattern of temperature detection elements. Instead of placing all detection elements at identical relative positions within their respective heating areas, the arrangement is made asymmetric with respect to the substrate's geometry, particularly adapting end portion detection element positions to compensate for greater heat loss at those locations.

Inventive Principle:

Principle #4Asymmetry

2Measurement precision

If temperature detection elements are positioned to detect average temperature in central areas, then central temperature control is accurate, but end portion temperature gradients are not properly detected

Engineering Contradiction:

Improveaverage temperature detection accuracyVSAvoidtemperature distribution information

Core Design Contradiction:

Measurement precisionVSLoss of information

Solution Approach 1:

The patent applies local quality by varying the position of temperature detection elements according to their location within the print element substrate. Detection elements in end portions are positioned differently from those in central portions, optimizing each location's measurement capability according to its specific thermal characteristics and heat loss patterns.

Inventive Principle:

Principle #3Local quality

3Device complexity

If all heating areas use identical element arrangements, then manufacturing is simplified, but temperature control precision deteriorates at end portions

Engineering Contradiction:

Improveelement arrangement complexityVSAvoidtemperature control precision

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The patent applies local quality by varying the position of temperature detection elements according to their location within the print element substrate. Detection elements in end portions are positioned differently from those in central portions, optimizing each location's measurement capability according to its specific thermal characteristics and heat loss patterns.

Inventive Principle:

Principle #3Local quality

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 configuration enables precise temperature detection and control, enhancing image quality by minimizing temperature unevenness and improving landing accuracy of ejected droplets.

Implementation Method 1

an energy generating element array configured with a plurality of energy generating elements arranged along a first direction to generate energy for ejecting the liquid

Methodology Applied

Scientific EffectEnergy generation for liquid ejection:

Implementation Method 2

a temperature detection element array configured with a plurality of temperature detection elements arranged along the first direction to detect a temperature of the print element substrate

Methodology Applied

Scientific EffectTemperature detection:

Implementation Method 3

a heating element array configured with a plurality of heating elements arranged along the first direction to heat the print element substrate

Methodology Applied

Scientific EffectHeating: Heating

Data Source

PatentUS20260027826A1Print element substrate, liquid ejection head, and liquid ejection apparatus

Publication Date: 2026.01.29 CANON KK

AI summary

The purpose of the present disclosure is to provide a print element substrate capable of accurately detecting temperature over the entire area and performing high-precision temperature control. The print element substrate includes an energy generating element array, a temperature detection element array, a heating element array, and a plurality of unit areas each including an energy generating element, a temperature detection element, and a heating element. Among the plurality of unit areas, compared to a first unit area arranged in a near of a center of the print element substrate, in a second unit area arranged at a position near a first end portion of the print element substrate, the temperature detection element is arranged at a position close to the first end portion.