Parallel Beam Flexure Mechanism for IPD Adjustment

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing mixed reality headsets face challenges in accommodating varying interpupillary distances (IPDs) of users, leading to binocular disparity errors that result in blurred images, discomfort, and loss of three-dimensional effect, due to the complexity and limited range of motion in current mechanical adjustment systems.

Innovation Solution

A parallel beam flexure mechanism (PBFM) is introduced, comprising flexures, a mounting platen, and a horizontal translation mechanism, which allows for adjustable interpupillary distance by horizontally translating the mounting platen and optical payload, thereby aligning the optical elements accurately for different users.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a mechanical adjustment system is used to vary the IPD of mixed reality headsets, then the IPD can be adjusted to accommodate different users, but the system becomes overly complex, bulky, and has limited range of motion

Engineering Contradiction:

ImproveIPD adjustment capabilityVSAvoidmechanical adjustment system complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent replaces traditional complex mechanical adjustment systems with a voice-activated control system that uses speech recognition to control IPD adjustment, thereby reducing mechanical complexity while maintaining adjustability

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the control parameter from manual mechanical operation to voice commands, allowing IPD adjustment through speech recognition and synthesis, which simplifies the mechanical structure while preserving the ability to accommodate different users

Inventive Principle:

Principle #35Parameter changes

2Adaptability or versatility

If the IPD of mixed reality headsets is designed to be as wide as possible, then both eye pupils can be positioned within the exit pupils, but users with smaller IPDs experience binocular disparity and position errors

Engineering Contradiction:

Improveaccommodation of different IPDsVSAvoidbinocular disparity accuracy

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent implements a dynamic IPD adjustment mechanism that allows the interpupillary distance to be changed based on individual user needs, transitioning from a fixed wide IPD design to an adjustable system that optimizes binocular alignment for each user

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent incorporates voice feedback and recognition systems that allow users to communicate their IPD requirements, enabling the system to adjust and maintain accurate binocular alignment through interactive control

Inventive Principle:

Principle #23Feedback

3Adaptability or versatility

If software approaches are used to provide corrective display adjustments, then IPD variation can be attempted, but they do not perform as well as mechanical adjustment systems

Engineering Contradiction:

ImproveIPD adjustment capabilityVSAvoidadjustment performance

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent introduces voice recognition and synthesis as an intermediary control layer between the user and the IPD adjustment mechanism, combining software-based control with reliable mechanical or actuated adjustment to achieve both ease of use and performance

Inventive Principle:

Principle #24Intermediary (Mediator)

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 PBFM provides a compact, lightweight, and effective mechanical adjustment system that smoothly adjusts the IPD, reducing binocular disparity errors and maintaining vertical alignment, thus enhancing user comfort and the three-dimensional effect in mixed reality environments.

Implementation Method 1

The first flexure is connected in a parallel arrangement with a third flexure that is attached to a frame of the optical device. The second flexure is connected in a parallel arrangement with a fourth flexure that is attached to the frame of the optical device. The optical payload and the horizontal translation mechanism are attached to the mounting platen, where the horizontal translation mechanism is configured to translate the mounting platen in a horizontal direction by bending the flexures.

Methodology Applied

Scientific EffectElasticity: Elasticity

Data Source

PatentUS10394033B2Parallel beam flexure mechanism for interpupillary distance adjustment

Publication Date: 2019.08.27 MICROSOFT TECHNOLOGY LICENSING LLC

AI summary

A parallel beam flexure mechanism (“PBFM”) for adjusting an interpupillary distance (“IPD”) of an optical device is disclosed. The PBFM includes a plurality of flexures, a mounting platen, an optical payload, and a horizontal translation mechanism. The mounting platen has a first end and a second end, where the mounting platen is attached to a first set of flexures that are in a parallel arrangement to a second set of flexures attached to a frame of an optical device, such as a head mounted display. The optical payload and horizontal translation mechanism are attached to the mounting platen, where the horizontal translation mechanism is configured to translate the mounting platen in a horizontal direction by bending the flexures, thereby adjusting the IPD of the optical device.