Electrically Adjustable Lens for Fundus Camera Astigmatism Compensation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional fundus cameras require expensive and prone-to-wear mechanical components, making it difficult to obtain focused images of the ocular fundus for a wide range of patients due to the need for precise mechanical adjustments.

Innovation Solution

An electrically adjustable lens with liquid crystal layers or two fluids separated by a phase boundary surface, allowing for adjustable refractive power and axis positioning, which simplifies the astigmatism compensation process and eliminates the need for precise mechanical displacement of optical components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If mechanical displacement of optical components is used to adjust focusing, then the device can accommodate different patient needs, but the device complexity and cost increase due to precise mechanical components

Engineering Contradiction:

Improveaccommodation of different patient needsVSAvoidmechanical components complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical displacement system with an electrically controllable lens system. The lens refractive power is adjusted by applying voltages to liquid crystal layers or deforming a phase boundary surface between two fluids, eliminating the need for mechanical displacement of optical components along the optical axis while maintaining the ability to accommodate different patient needs.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the physical state of the lens by using liquid crystal layers or a phase boundary surface between two fluids. By applying voltages, the refractive power of the lens is electrically adjusted, allowing focusing adaptation to different patient needs without mechanical component displacement.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If mechanical displacement components are used for focusing adjustment, then the focusing range can be achieved, but the reliability decreases due to wear and precision requirements

Engineering Contradiction:

Improvedurability of componentsVSAvoidprecision of mechanical components

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The patent replaces mechanical displacement components with an electrically controllable lens system. The lens refractive power is adjusted by applying voltages to liquid crystal layers or deforming a phase boundary surface, eliminating mechanical wear and the need for high-precision mechanical components while maintaining reliable focusing adjustment.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Adaptability or versatility

If the optical system is displaced along the optical axis, then focused images can be obtained for different patients, but the device complexity and cost increase

Engineering Contradiction:

Improvefocusing range for different patientsVSAvoidmanufacturing simplicity

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent replaces the mechanical displacement of the optical system with an electrically controllable lens. The lens refractive power is adjusted by applying voltages to liquid crystal layers or deforming a phase boundary surface between two fluids, simplifying the device structure and manufacturing while maintaining the ability to obtain focused images for different patients.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the refractive power parameter of the lens electrically through voltage application to liquid crystal layers or phase boundary deformation, replacing the need for mechanical displacement of the optical system. This simplifies manufacturing while maintaining adaptability for different patients.

Inventive Principle:

Principle #35Parameter changes

4Adaptability or versatility

If the image recorder is displaced along the optical axis, then focused images can be obtained, but the device complexity and cost increase

Engineering Contradiction:

Improvefocusing capabilityVSAvoidmechanical displacement mechanism

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical displacement of the image recorder with an electrically controllable lens. The lens refractive power is adjusted by applying voltages to liquid crystal layers or deforming a phase boundary surface, eliminating the need for mechanical displacement mechanisms while maintaining focusing capability for different patients.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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

Enables focused imaging of the ocular fundus for a greater majority of patients with simpler and more durable optical components, reducing the complexity and cost of the imaging process while allowing for rapid focusing and automatic adjustment.

Implementation Method 1

The electrically adjustable lens can have liquid crystal layers

Methodology Applied

Scientific EffectLiquid crystal effect: Liquid Crystals

Implementation Method 2

two fluids contained in a container, between which fluids a phase boundary surface is embodied that can be deformed by applying a voltage

Methodology Applied

Scientific EffectElectrowetting effect: Electrowetting

Data Source

PatentUS7726815B2Focusing and astigmatism compensation device for a fundus camera

Publication Date: 2010.06.01 CARL ZEISS MEDITEC AG

AI summary

The invention relates to a device for observing the ocular fundus, in particular to a fundus camera. Said device comprises a light source (1b) for the provision of illumination radiation, an illumination optical path for directing the illumination radiation onto the ocular fundus and observation optics for reproducing the illuminated ocular fundus, the observation optics comprising a module (16b), whose refractive power can be electrically adjusted.