Fresnel Lens Film Stack for 3D Decorative Patterns

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing decorative films fail to produce visually distinctive and three-dimensional patterns using Fresnel lenses effectively, as they lack innovative configurations that combine differently oriented Fresnel lens films with diffusers and indicia to create aesthetically pleasing effects.

Innovation Solution

A film stack comprising two optical films with structured surfaces featuring Fresnel lenses oriented non-parallel to each other, combined with a diffuser and indicia, produces a 3-dimensional appearance by alternating focusing and defocusing lenses, and incorporating a sinusoidal slope sequence for the facets to create unique visual effects.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If Fresnel lenses are used in decorative films, then optical functionality is improved, but visual distinctiveness and three-dimensional appearance are not achieved

Engineering Contradiction:
Improveoptical functionalityVSAvoidthree-dimensional appearance
Core Design Contradiction:
Illumination intensityVSShape

Solution Approach 1:

The patent combines multiple optical films with Fresnel lenses oriented at different angles into a single stack, merging their optical effects to produce three-dimensional appearance and visual distinctiveness that individual films cannot achieve alone

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent introduces angular orientation as a new dimension for configuring Fresnel lenses, arranging them at different angles relative to each other in the stack, which transforms the flat two-dimensional optical effect into a three-dimensional visual appearance

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Shape

If multiple optical films with Fresnel lenses are stacked, then three-dimensional appearance is improved, but device complexity increases

Engineering Contradiction:
Improvethree-dimensional appearanceVSAvoidstack configuration
Core Design Contradiction:
ShapeVSDevice complexity

Solution Approach 1:

The patent divides the optical system into multiple discrete film layers, each containing Fresnel lenses with specific orientations, allowing independent design and manufacturing of each layer while achieving complex overall optical effects when stacked

Inventive Principle:
Principle #1Segmentation

3Illumination intensity

If diffusers are added to scatter light, then soft appearance is improved, but light transmission is reduced

Engineering Contradiction:
Improvesoft appearanceVSAvoidlight transmission
Core Design Contradiction:
Illumination intensityVSLoss of energy

Solution Approach 1:

The patent applies diffusers selectively within the film stack rather than uniformly across all films, creating localized light scattering in specific regions while maintaining higher light transmission in other areas, thus achieving soft appearance without excessive light loss

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

The solution achieves visually distinctive and aesthetically pleasing patterns by scattering light and altering the focal points of Fresnel lenses, providing a soft and multicolored appearance that enhances the decorative value of the films.

Implementation Method 1

each film having a structured surface with facets that define a plurality of Fresnel lenses

Methodology Applied
Scientific EffectFresnel lens: Fresnel Lens

Implementation Method 2

At least some of the first Fresnel lenses, and at least some of the second Fresnel lenses, may be configured to focus incident parallel light

Methodology Applied
Scientific EffectFocusing: Focusing

Implementation Method 3

a diffuser disposed to scatter light transmitted by the first and/or second Fresnel lenses

Methodology Applied
Scientific EffectLight scattering: Scattering

Implementation Method 4

The structured surface defining the Fresnel lenses may have transmissive facets arranged in a cyclic (for example, sinusoidal) slope sequence from substantially zero to a maximum positive slope to substantially zero to a maximum negative slope and back to substantially zero

Methodology Applied
Scientific EffectRefraction: Refraction

Data Source

PatentEP2870494B1Decorative film articles utilizing fresnel lens films
Publication Date: 2019.09.25 3M INNOVATIVE PROPERTIES CO
  • EP2870494B1 patent drawingFigure 1
  • EP2870494B1 patent drawingFigure 2
  • EP2870494B1 patent drawingFigure 3

AI summary

First and second optical films in a stack each have a structured surface defining extended Fresnel lenses. First and second Fresnel lenses of the respective first and second films extend generally parallel to different first and second in-plane axes respectively. The films may be attached together such that light transmitted by one film is intercepted by the other. The film stack may also include a diffuser disposed to scatter light transmitted by the optical film(s). Other disclosed decorative articles include an individual optical film having a structured surface with transmissive facets arranged in a cyclic slope sequence from substantially zero to a maximum positive slope to substantially zero to a maximum negative slope and back to substantially zero, the sequence repeating over some or all of the structured surface. The slope sequence may define alternating focusing and defocusing Fresnel lenses, and the Fresnel lenses may be extended and linear.