Wavefront Sensor for Ophthalmic Lens Metrology
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for measuring ophthalmic lenses, especially those formed using free-form techniques, face challenges in obtaining accurate and efficient non-contact optical measurements due to the complexity of injection molding processes and the need for customized lenses specific to individual patients or applications.
Innovation Solution
The use of an optical digital wavefront sensor apparatus that employs a digital wavefront camera and a three-lens mandrel cancellation system to obtain simultaneous measurements of intensity and phase without physical contact, allowing for real-time, high-resolution, and vibration-insensitive wavefront analysis of ophthalmic devices, including dry contact lenses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional optical metrology methods are used to measure ophthalmic lenses, then measurement capability is provided, but measurement accuracy and efficiency are insufficient for free-form lenses and customized lenses
Solution Approach 1:
The patent replaces conventional mechanical/optical metrology systems with a digital wavefront sensor system that uses wavefront analysis to measure lens characteristics. The wavefront sensor captures phase and amplitude information of light passing through the lens, enabling non-contact, high-precision measurement of free-form surfaces without mechanical contact or complex alignment procedures.
Solution Approach 2:
The patent creates a digital copy of the lens wavefront characteristics by capturing the optical wavefront information and processing it into measurable parameters. This digital representation allows for accurate analysis of lens properties including spherical equivalent, cylinder, and axis without physical manipulation of the lens.
2Productivity
If injection molding processes are used to form lenses, then mass production capability is achieved, but customization capability for individual patients is lost
Solution Approach 1:
The patent enables lens customization by allowing modification of optical parameters such as spherical equivalent, cylinder, and axis based on individual patient measurements. The wavefront sensor system captures patient-specific optical characteristics, and these parameters are adjusted to create customized lens prescriptions while maintaining the efficiency of the measurement process.
3Adaptability or versatility
If free-form techniques are used to create customized lenses, then customization capability is improved, but measurement complexity increases
Solution Approach 1:
The patent simplifies measurement of complex free-form lenses by replacing traditional mechanical measurement methods with wavefront analysis. The digital wavefront sensor automatically captures and processes the optical information, eliminating the need for complex mechanical alignment and manual measurement procedures.
Solution Approach 2:
The wavefront sensor system performs self-alignment and automatic measurement of free-form lens surfaces. The system independently captures the wavefront information and processes it to extract lens parameters, reducing the need for operator intervention and complex setup procedures.
4Stability of the object's composition
If contact-based measurement methods are used, then measurement stability is achieved, but risk of lens contamination and damage increases
Solution Approach 1:
The patent eliminates mechanical contact between measurement devices and the lens by using optical wavefront analysis. Light passes through the lens and the wavefront sensor captures the transmitted wavefront information, providing stable measurements without physical contact that could cause contamination or damage to the lens surface.
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 fast, accurate, and cost-efficient measurement of ophthalmic devices with high dynamic range and spatial resolution, facilitating the production of customized lenses by providing direct visualization of intensity and wavefront data.
Implementation Method 1
uses an optical digital wavefront sensor... to obtain simultaneous measurements of intensity and phase of the transmitted wavefront
Implementation Method 2
a three-lens mandrel cancellation system to obtain simultaneous measurements of intensity and phase
Data Source
Figure 1
Figure 2
Figure 3~3A
AI summary
This invention provides for a method and a wavefront measuring apparatus used to measure, in one or continuous measurements, one or more ophthalmic devices directly on a forming mandrel, in non-hydrated state and in a much faster way with high spatial resolution.