Compact Eyeglass Measurement Device Using Image Processing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for measuring morpho-geometrical parameters of eyeglasses, such as pupillary distance and pantoscopic angle, are either bulky and inflexible or require complex and constraining positioning of the wearer, making them inefficient and difficult to use.

Innovation Solution

A compact, flexible measurement device comprising a tablet with a high-resolution camera, inclinometer, and touch screen, allowing for accurate and comfortable measurement of morpho-geometrical parameters without the need for specific positioning or equipment, using a target and flash for improved lighting and image processing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a vertical measurement column of large size is used, then measurement accuracy is improved, but the device becomes bulky and requires large premises

Engineering Contradiction:
Improvemeasurement accuracyVSAvoiddevice size
Core Design Contradiction:
Measurement precisionVSArea of stationary object

Solution Approach 1:

The measurement system is divided into separate functional components: a portable measurement device with camera and illuminator that can be positioned independently, and a display device that can be placed on standard tables or countertops. This segmentation allows accurate measurements to be taken in smaller spaces without requiring a single large integrated structure.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention transitions from a vertically-oriented large measurement column to a horizontally-oriented compact setup where the camera and illuminator are positioned at table level. By changing the spatial arrangement from vertical to horizontal configuration, the system achieves similar measurement capabilities in a much smaller footprint.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Adaptability or versatility

If a compact measurement device is used, then flexibility and ease of movement are improved, but measurement precision may be compromised

Engineering Contradiction:
ImproveflexibilityVSAvoidmeasurement accuracy
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The invention replaces complex mechanical positioning systems with digital image processing and computational methods. The camera captures images of the wearer's face and eyeglasses, and software algorithms automatically calculate pupillary distance, lens height, and pantoscopic angle from these images, eliminating the need for bulky mechanical measurement mechanisms while maintaining precision.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The invention introduces an intermediary computational layer that processes images captured by the compact camera. Specialized software acts as a mediator between the simple image capture function and the complex measurement requirements, extracting precise morpho-geometrical parameters through image analysis and geometric calculations.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Measurement precision

If complex positioning equipment is used, then measurement accuracy is improved, but the ease of operation and user comfort are reduced

Engineering Contradiction:
Improvemeasurement accuracyVSAvoiduser comfort
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The measurement system performs measurements automatically without requiring the wearer to adopt specific positions or manipulate measurement tools. The wearer simply looks at the camera, and the system's image processing algorithms automatically detect facial features, eyeglass positions, and calculate all required parameters, making the process comfortable and effortless for the user.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

Instead of requiring the measurement device to adapt to complex wearer positions, the invention inverts the approach by having the wearer maintain a natural, comfortable position while the device captures images from which all measurements are computationally derived. The system adapts to the wearer's natural posture rather than requiring the wearer to adapt to the system.

Inventive Principle:
Principle #13The other way round (Inversion)

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 quick, accurate, and reliable measurement of morpho-geometrical parameters with minimal user constraint, providing instant results and adaptability for various situations.

Implementation Method 1

the person wearing the eyeglasses looking at their own reflection in a mirror

Methodology Applied
Scientific EffectLight reflection: Reflection

Implementation Method 2

a flash, both to obtain better control over lighting conditions and to make the corneal reflections of each eye visible

Methodology Applied
Scientific EffectLight emission: Light

Data Source

PatentEP2761365B1MEASUREMENT apparatus OF MORPHO-GEOMETERICAL PARAMETERS OF A PERSON WEARING EYEGLASSES
Publication Date: 2018.12.05 ESSILOR INTERNATIONAL(COMPAGNIE GENERALE D OPTIQUE)
  • EP2761365B1 patent drawingFigure 1~2
  • EP2761365B1 patent drawingFigure 3~4
  • EP2761365B1 patent drawingFigure 5~6

AI summary

The invention relates to a method of measuring morpho-geometrical parameters of a person wearing eyeglasses (21), fitted with position-identification means (22), the method making use of an independent computer device (1, 10) comprising a screen, a target (8, 18), a compact image acquisition system (7, 17) having means for determining its angle of inclination, and a computer. The main characteristic of a method of the invention is that it comprises the following steps: . causing the person to observe a point situated in front at infinity while holding the head naturally on a direction (24) that is substantially horizontal; · acquiring a first image of the position of the frame (21) in this first posture; . causing the person to observe the target (8, 18) placed in a known position relative to the image acquisition system, by adopting a position that is natural and comfortable and that involves at least a tilting movement of the head; . acquiring a second image of the position of the frame (21) in this second posture; . determining the positions of the eyes (27) from one of the two images; . computer processing of the two images obtained in order to determine the morpho-geometrical parameters of the person; and . delivering the results of the measurements.