Thermally Expandable Sheet 3D Image Density Control

Solution Overview

Problem

The existing methods for forming three-dimensional images using thermally expandable sheets suffer from color display issues due to surface stretching and area increase when the thermally expandable layer expands, leading to pale and non-uniform color development.

Innovation Solution

A method and apparatus that form a mirror image on the back of the thermally expandable sheet with a photothermal conversion material, allowing for controlled expansion and maintaining the original density of the display color by adjusting the density of the surface image in anticipation of the expansion, using a printer and light source to generate thermal energy and create the three-dimensional image.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Volume of moving object

If the thermally expandable layer is heated and expanded to form a three-dimensional image, then the volume and shape of the image are improved, but the surface area increases causing color density to decrease and color uniformity to deteriorate

Engineering Contradiction:

Improvevolume of three-dimensional imageVSAvoidcolor density uniformity

Core Design Contradiction:

Volume of moving objectVSManufacturing precision

Solution Approach 1:

The patent applies preliminary action by pre-adjusting the ink density distribution before thermal expansion. The controller increases ink density in regions that will undergo greater expansion and decreases ink density in regions with lesser expansion. This anticipatory adjustment ensures that after the thermally expandable layer expands and surface area increases, the color density remains uniform across the entire image.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements parameter changes by dynamically adjusting the ink density parameter based on the expansion characteristics of different regions. The controller calculates the relationship between ink density and expansion rate, then modifies the ink density parameter accordingly. This allows the color density to be maintained at a constant level despite variations in surface area caused by differential expansion.

Inventive Principle:

Principle #35Parameter changes

2Shape

If the thermally expandable layer is expanded by heating, then the three-dimensional shape is achieved, but the surface stretching causes color development to become non-uniform and pale

Engineering Contradiction:

Improvethree-dimensional shapeVSAvoidcolor development uniformity

Core Design Contradiction:

ShapeVSManufacturing precision

Solution Approach 1:

The patent applies preliminary action by pre-adjusting the ink density distribution before thermal expansion. The controller increases ink density in regions that will undergo greater expansion and decreases ink density in regions with lesser expansion. This anticipatory adjustment ensures that after the thermally expandable layer expands and surface area increases, the color density remains uniform across the entire image.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements parameter changes by dynamically adjusting the ink density parameter based on the expansion characteristics of different regions. The controller calculates the relationship between ink density and expansion rate, then modifies the ink density parameter accordingly. This allows the color density to be maintained at a constant level despite variations in surface area caused by differential expansion.

Inventive Principle:

Principle #35Parameter changes

3Use of energy by moving object

If light is used to heat and expand the thermally expandable layer, then energy efficiency is improved compared to direct heating, but control precision of expansion uniformity becomes more difficult

Engineering Contradiction:

Improveenergy efficiency of heatingVSAvoidexpansion uniformity control

Core Design Contradiction:

Use of energy by moving objectVSManufacturing precision

Solution Approach 1:

The patent applies feedback by implementing a control system that monitors and adjusts ink density based on expansion characteristics. The controller calculates the relationship between ink density and expansion rate, then modifies the ink density parameter to compensate for non-uniform expansion. This feedback mechanism ensures that despite using light heating which may cause differential expansion, the final color density remains uniform across the image.

Inventive Principle:

Principle #23Feedback

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 ensures that the three-dimensional image maintains intended color density and development quality despite the expansion of the thermally expandable layer, preventing color pale and non-uniformity issues.

Implementation Method 1

forming a second print image on a region of the other surface of the thermally expandable sheet with a photothermal conversion material, the second print image being to be a mirror image of the first print image

Methodology Applied

Scientific EffectPhotothermal conversion: Photoacoustic Effect

Implementation Method 2

forming a three-dimensional image of the first print image by selectively expanding the thermally expandable layer with thermal energy that is generated in the second print image

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentUS9522490B2Method and apparatus for forming three-dimensional image

Publication Date: 2016.12.20 CASIO COMPUTER CO LTD

AI summary

There are provided a method and apparatus for forming a three-dimensional image. The method and apparatus adjust the density in consideration of the influence of the expansion of a thermally expandable layer on the density of a display color or a color development state so that the originally planned density of the display color can be achieved, on the surface of a thermally expandable sheet. The method and apparatus form a mirror image of a colored image, of which the density of a black component is adjusted so as to correspond to the bulge height of the thermally expandable layer, on the back of the thermally expandable sheet. The method and apparatus expand the thermally expandable layer when irradiating the thermally expandable layer with light, which includes infrared wavelengths, from the back of the thermally expandable sheet.