Tunable Acoustic Gradient Index Lens for High-Speed Beam Modulation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current adaptive optical technologies, such as digital mirror arrays and spatial light modulators, face limitations in speed, energy throughput, and cost, making them unsuitable for high-energy/high-power laser processing and large-scale applications, where rapid control over beam properties is necessary.

Innovation Solution

A tunable acoustic gradient index of refraction (TAG) lens is developed, utilizing a casing with a piezoelectric element to alter the refractive index of a fluid within, allowing for rapid modulation of light beams through acoustic waves, enabling dynamic focusing and imaging.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If digital mirror arrays or spatial light modulators are used for adaptive optical control, then beam property modulation capability is improved, but switching speed and energy throughput are limited

Engineering Contradiction:

Improvebeam property modulation capabilityVSAvoidswitching speed

Core Design Contradiction:

Adaptability or versatilityVSSpeed

Solution Approach 1:

The patent replaces mechanical mirror arrays and liquid crystal spatial light modulators with a purely acoustic system. Acoustic waves are used to create dynamic refractive index gradients in a fluid medium, eliminating mechanical moving parts and enabling faster response times in the megahertz range while maintaining adaptive beam control capabilities

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The invention changes the fundamental operating parameter from mechanical/electrical switching to acoustic wave frequency modulation. By controlling the frequency and amplitude of acoustic waves, the refractive index distribution is dynamically adjusted, enabling rapid beam property modulation without the speed limitations of conventional devices

Inventive Principle:

Principle #35Parameter changes

2Adaptability or versatility

If digital mirror arrays or spatial light modulators are used, then adaptive optical control is achieved, but cost increases and energy throughput decreases

Engineering Contradiction:

Improveadaptive optical controlVSAvoidenergy throughput

Core Design Contradiction:

Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The patent replaces energy-intensive mechanical and electro-optical systems with an acoustic field-based system. Acoustic waves require significantly less energy to generate the necessary refractive index changes, enabling high energy throughput while maintaining adaptive optical control functionality

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The invention utilizes phase changes in the acoustic field (sound wave propagation) to induce refractive index variations in the fluid medium. This acoustic-to-optical coupling mechanism is highly energy-efficient compared to mechanical actuation or liquid crystal switching, allowing sustained adaptive control with lower energy consumption

Inventive Principle:

Principle #36Phase transitions

3Device complexity

If fixed lenses are used, then simplicity is maintained, but ability to rapidly change beam properties is lost

Engineering Contradiction:

Improvesystem simplicityVSAvoidbeam property change capability

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent transforms a static fixed lens system into a dynamic system by introducing acoustic waves that continuously modulate the refractive index distribution. This creates a time-varying lens effect where beam properties such as focus, shape, and direction can be rapidly changed without mechanical movement, maintaining simplicity while adding adaptability

Inventive Principle:

Principle #15Dynamics

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 TAG lens provides fast and efficient control over light beam properties, overcoming the limitations of existing technologies by enabling rapid and precise modulation of light intensity and wavefront, suitable for high-energy applications and large-scale processing.

Implementation Method 1

A piezoelectric element may be provided within the casing in acoustic communication with the cavity for delivering an acoustic wave to the cavity to alter the refractive index of the refractive material

Methodology Applied

Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

a tunable acoustic gradient index of refraction (TAG) lens... capable of changing its refractive index in response to application of an acoustic wave thereto

Methodology Applied

Scientific EffectAcousto-optic effect: Acousto-optic Effect

Data Source

PatentUS9256009B2Tunable acoustic gradient index of refraction lens and system

Publication Date: 2016.02.09 MITUTOYO CORP

AI summary

A microscope, comprising a stage onto which is placed an item, a lens having a tunable acoustic gradient index of refraction (TAG lens) sufficiently proximate to said stage to magnify an image of the item, a viewing point for providing for viewing of the magnified image, and a pulsed illuminator capable of illuminating the stage and synchronously pulsed with an operating frequency of the TAG lens.