Multifocus Meta-Lens Using Liquid Crystal and Nanostructures

Solution Overview

Problem

Conventional lenses for implementing multifocality in holograms and augmented/virtual reality displays are bulky and heavy, limiting their application due to difficulties in achieving multiple focal points within the visible light range.

Innovation Solution

A multifocus meta-lens comprising a liquid crystal layer and a meta-lens with nanostructures on its surface, allowing for the formation of two or more multifocal points by adjusting the polarization state of incident light, utilizing a hydrogenated amorphous silicon (a-Si:H) nanostructure and a fused silica glass substrate for high transmission efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a conventional lens is used to implement multifocality, then multiple focal points can be achieved, but the system becomes heavy and occupies large volume

Engineering Contradiction:

ImprovemultifocalityVSAvoidsystem weight

Core Design Contradiction:

Adaptability or versatilityVSWeight of moving object

Solution Approach 1:

The patent replaces the mechanical system of moving bulky glass-based optical devices with a meta-lens system that uses nanostructures on a flat substrate. The meta-lens achieves multifocality through nanoscale structural design rather than mechanical movement, dramatically reducing weight and volume while maintaining the ability to form multiple focal points.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the physical parameters of the lens by using nanostructures with specific geometric characteristics (size, shape, orientation) to control light focusing. By adjusting these nanoscale parameters rather than relying on bulk material properties, the system achieves multifocality in an ultra-thin configuration, resolving the contradiction between multifocality and compact size.

Inventive Principle:

Principle #35Parameter changes

2Adaptability or versatility

If a conventional lens is used to implement multifocality, then multiple focal points can be achieved, but the system occupies large volume

Engineering Contradiction:

ImprovemultifocalityVSAvoidsystem volume

Core Design Contradiction:

Adaptability or versatilityVSVolume of moving object

Solution Approach 1:

The patent replaces the mechanical system of moving bulky glass-based optical devices with a meta-lens system that uses nanostructures on a flat substrate. The meta-lens achieves multifocality through nanoscale structural design rather than mechanical movement, dramatically reducing weight and volume while maintaining the ability to form multiple focal points.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent transitions from three-dimensional bulk optical components to two-dimensional nanostructure arrays on a flat surface. By encoding focusing functionality in the nanoscale geometry rather than relying on thick lens materials, the system achieves multifocality with minimal volume, effectively solving the space occupation problem.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Weight of moving object

If a light and thin meta-lens is used, then weight and volume are reduced, but multifocality in the visible light range becomes difficult to achieve

Engineering Contradiction:

Improvelens weightVSAvoidmultifocality

Core Design Contradiction:

Weight of moving objectVSAdaptability or versatility

Solution Approach 1:

The patent changes the physical parameters of the lens by using nanostructures with specific geometric characteristics (size, shape, orientation) to control light focusing. By adjusting these nanoscale parameters rather than relying on bulk material properties, the system achieves multifocality in an ultra-thin configuration, resolving the contradiction between multifocality and compact size.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs composite structural design combining meta-lens nanostructures with liquid crystal layers. This composite approach enables the system to achieve multifocality in the visible light range while maintaining ultra-thin profile and low weight, overcoming the limitations of single-material approaches.

Inventive Principle:

Principle #40Composite materials

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 provides a lightweight, ultra-thin lens capable of forming multiple focal points, enabling real-time focus adjustment and application in hologram devices, augmented/virtual reality displays, and variable beam steering with high transmission efficiency.

Implementation Method 1

a liquid crystal layer

Methodology Applied

Scientific EffectLiquid crystal: Liquid Crystals

Implementation Method 2

a meta-lens coupled to one or both surfaces of the liquid crystal layer, wherein a nanostructure is formed on a surface of the meta-lens

Methodology Applied

Scientific EffectRefraction: Refraction

Data Source

PatentUS20240027823A1Multi-focusing meta lens

Publication Date: 2024.01.25 POSCO HLDG INC

AI summary

The present disclosure relates to a lens that can be used for a hologram, an augmented/virtual reality display, and the like, and more particularly, to a meta-lens using a meta surface.