MEMS Light Deflection with Angle-Expanding Diffraction Optics

Solution Overview

Problem

Existing laser light deflection techniques, such as those using gimbal mirrors or rotary stages, are not suitable for systems requiring reduced size, weight, or low power consumption due to their mechanical complexity.

Innovation Solution

A light deflection device incorporating a MEMS light deflection element with a diffraction element having varying periodic structure pitches, combined with an angle increasing optical element like a liquid crystal diffraction element, to enhance deflection angles without increasing size or weight.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a gimbal mirror or rotary stage is used for laser light deflection, then the deflection control is direct and simple, but the size and weight of the system increase

Engineering Contradiction:

Improvedeflection control simplicityVSAvoidsystem weight

Core Design Contradiction:

Ease of operationVSWeight of moving object

Solution Approach 1:

The patent replaces the mechanical gimbal mirror or rotary stage system with a MEMS (Micro-Electro-Mechanical Systems) light deflection element. This substitution eliminates the need for large mechanical moving parts while maintaining the light deflection function, thereby significantly reducing system weight and size while keeping the deflection control simple through electrical actuation of the MEMS device.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces an angle increasing optical element that modifies the angular parameter of the deflected light. By placing this element downstream of the MEMS deflection element, the system achieves enhanced deflection angles without requiring larger mechanical components, thus maintaining compact size while improving deflection capability.

Inventive Principle:

Principle #35Parameter changes

2Ease of operation

If a gimbal mirror or rotary stage is used for laser light deflection, then the deflection control is direct and simple, but the power consumption increases

Engineering Contradiction:

Improvedeflection control simplicityVSAvoidpower consumption

Core Design Contradiction:

Ease of operationVSUse of energy by moving object

Solution Approach 1:

The patent replaces the mechanical gimbal mirror or rotary stage system with a MEMS (Micro-Electro-Mechanical Systems) light deflection element. This substitution eliminates the need for large mechanical moving parts while maintaining the light deflection function, thereby significantly reducing system weight and size while keeping the deflection control simple through electrical actuation of the MEMS device.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces an angle increasing optical element that modifies the angular parameter of the deflected light. By placing this element downstream of the MEMS deflection element, the system achieves enhanced deflection angles without requiring larger mechanical components, thus maintaining compact size while improving deflection capability.

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If the MEMS light deflection element has both light collecting and emitting functions, then the device structure is simplified, but the optical element design becomes more complex

Engineering Contradiction:

Improvedevice structureVSAvoidoptical element design

Core Design Contradiction:

Device complexityVSEase of manufacture

Solution Approach 1:

The patent combines the light collecting function and light emitting function into a single MEMS light deflection element. This merging of functions reduces the overall device structure by eliminating the need for separate collecting and emitting optical components, thereby simplifying the device while the specialized design of the integrated element addresses the manufacturing complexity through unified optimization.

Inventive Principle:

Principle #5Merging (Combining)

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 device achieves increased deflection angles while maintaining a compact structure, suitable for applications requiring reduced size and weight, and low power consumption.

Implementation Method 1

a diffraction element having different periodic structure pitches in a plane

Methodology Applied

Scientific EffectDiffraction: Diffraction

Implementation Method 2

the diffraction element in the MEMS light deflection element is a liquid crystal diffraction element

Methodology Applied

Scientific EffectLiquid crystal optical modulation: Liquid Crystals

Implementation Method 3

a liquid crystal diffraction element

Methodology Applied

Scientific EffectDiffraction: Diffraction

Implementation Method 4

the liquid crystal diffraction element includes a cholesteric liquid crystal layer, the cholesteric liquid crystal layer has a liquid crystal alignment pattern in which a direction of an optical axis derived from a liquid crystal compound changes while continuously rotating

Methodology Applied

Scientific EffectCholesteric liquid crystal helical structure: Cholesteric Liquid Crystal

Implementation Method 5

a MEMS light deflection element that deflects incident light to be emitted; and an angle increasing optical element

Methodology Applied

Scientific EffectLight reflection: Reflection

Data Source

PatentUS12449652B2Light deflection device and optical device

Publication Date: 2025.10.21 FUJIFILM CORP

AI summary

A light deflection device having a simple structure suitable for reducing the size and weight where a deflection angle can be increased, and an optical device including the light deflection device. The light deflection device includes: a MEMS light deflection element that deflects incident light to be emitted; and an angle increasing optical element that is disposed downstream of the light deflection element in a light traveling direction and increases an angle range of a deflection angle of light emitted from the light deflection element, in which the MEMS light deflection element has a function of collecting and emitting incident light.