Multi-Axis Microscanner Frequency Control for Stable Lissajous Scanning

Solution Overview

Problem

Existing Lissajous micro-scanners experience fluctuations in frequency ratio due to detuning of drive frequencies, leading to image disturbances such as flickering and poor coverage, especially under temperature fluctuations.

Innovation Solution

A method to control the drive frequencies of a multi-axis micro-scanner system by varying them in a way that counteracts changes in the frequency ratio, maintaining a stable frequency ratio even under detuning conditions, ensuring a uniform and high-quality projection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If drive frequencies are varied to compensate for detuning, then adaptability to temperature fluctuations is improved, but frequency ratio stability deteriorates

Engineering Contradiction:

Improveadaptability to temperature fluctuationsVSAvoidfrequency ratio stability

Core Design Contradiction:

Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The control device continuously monitors the actual frequency ratio between the two oscillation axes and compares it to a reference value. Based on this feedback, the controller dynamically adjusts the drive frequencies to maintain the correct Lissajous figure, compensating for temperature-induced detuning while preserving frequency ratio stability.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system dynamically changes the drive frequency parameters in response to detected frequency ratio deviations. By adjusting the drive frequencies as control parameters, the system adapts to temperature fluctuations while maintaining the stability of the frequency ratio through closed-loop control.

Inventive Principle:

Principle #35Parameter changes

2Stability of the object's composition

If drive frequencies are kept constant, then frequency ratio stability is improved, but adaptability to detuning conditions deteriorates

Engineering Contradiction:

Improvefrequency ratio stabilityVSAvoidadaptability to detuning conditions

Core Design Contradiction:

Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The control device continuously monitors the actual frequency ratio between the two oscillation axes and compares it to a reference value. Based on this feedback, the controller dynamically adjusts the drive frequencies to maintain the correct Lissajous figure, compensating for temperature-induced detuning while preserving frequency ratio stability.

Inventive Principle:

Principle #23Feedback

3Ease of operation

If drive frequencies are independently controlled, then ease of operation is improved, but image quality deteriorates due to frequency ratio fluctuations

Engineering Contradiction:

Improveindependent drive controlVSAvoidimage quality

Core Design Contradiction:

Ease of operationVSManufacturing precision

Solution Approach 1:

The control device continuously monitors the actual frequency ratio between the two oscillation axes and compares it to a reference value. Based on this feedback, the controller dynamically adjusts the drive frequencies to maintain the correct Lissajous figure, compensating for temperature-induced detuning while preserving frequency ratio stability.

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 stabilizes the Lissajous figure, achieving low-flicker and stable image quality over time by maintaining the frequency ratio, thus enhancing projection quality.

Implementation Method 1

a micro-scanner system for deflecting an electromagnetic beam can thus in particular have a two-axis micro-scanner, i.e. a micro-scanner with two different, non parallel, in particular mutually orthogonal, oscillation axes

Methodology Applied

Scientific EffectElastic deformation: Elasticity

Implementation Method 2

a mirror plate (deflection plate) that is suspended laterally on elastically stretchable springs

Methodology Applied

Scientific EffectReflection: Reflection

Data Source

PatentUS20260050156A1Multi-axis microscanner system, and method and apparatus for controlling the drive thereof

Publication Date: 2026.02.19 OQMENTED GMBH

AI summary

A method for controlling a drive for a multi-axis, in particular two-axis, micro-scanner system. As part of the method, a drive device for the micro-scanner system is controlled in such a way that the micro-scanner system is thereby caused to perform a first rotational oscillation of a deflection element of the micro-scanner system about a first oscillation axis by means of excitation at a first drive frequency and, simultaneously with the first oscillation, a second rotational oscillation of a deflection element of the micro-scanner system about a second oscillation axis which is not parallel to the first oscillation axis, in particular orthogonal thereto, by means of excitation at a second drive frequency, wherein these drive frequencies are respectively varied in time. The drive frequencies are varied over time in such a way that a change in the frequency ratio between the two drive frequencies is counteracted at the same time. While the drive frequencies themselves change, a change in the frequency ratio is counteracted.