Automated Reading Acuity Calibration with Infrared Distance Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current visual acuity tests, such as the Snellen chart, are inadequate for precise measurements, especially in cases like diabetic retinopathy, as they require manual calibration of distance measurements and do not account for randomized sentence presentation or reading speed adjustments for misread words.
Innovation Solution
A computer-based system that displays sentences with variable font sizes on a monitor, allows for real-time distance measurement using infrared cameras, and adjusts reading speed calculations based on misread words, providing automated calibration and randomized sentence presentation to improve accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If manual calibration is used to measure distance between patient and presentation surface, then measurement can be performed, but the process is tedious and time-consuming
Solution Approach 1:
The system performs automatic calibration without requiring manual intervention. The computer-controlled presentation surface automatically adjusts and calibrates the display based on pre-programmed parameters, eliminating the need for operators to manually measure and adjust distance settings.
Solution Approach 2:
The patent replaces manual mechanical calibration processes with an automated computer-controlled system. The presentation surface is controlled by a computer that automatically adjusts display parameters based on calculated distances, substituting manual measurement and adjustment with automated electronic control.
2Reliability
If sentences are presented in a fixed sequence on the screen, then the test procedure is simple, but patients can familiarize themselves with previously presented sentences
Solution Approach 1:
The system dynamically randomizes the presentation sequence of sentences on the display screen. Instead of a fixed sequence, sentences are presented in randomized order determined by a computer algorithm, preventing patients from anticipating or remembering previous sentences while maintaining systematic test progression.
3Measurement precision
If reading speed is calculated without adjusting for misread words, then calculation is simpler, but reading acuity measurement is less accurate
Solution Approach 1:
The system incorporates feedback mechanisms where the computer monitors and records which words are misread by the patient. This feedback information is then used to adjust the reading speed calculation, ensuring that misread words are accounted for in the final reading acuity measurement.
Solution Approach 2:
The system pre-programs the complete set of sentences and their correct word sequences before the test begins. This preliminary preparation allows the computer to automatically compare patient responses against the predetermined correct answers and adjust calculations accordingly.
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 system enables precise and efficient measurement of reading acuity by automatically calibrating distance and adjusting for reading speed, reducing test duration and operator error, while preventing familiarization with previously presented sentences.
Implementation Method 1
The cameras are manually calibrated to detect how far the sensor on the reader's face is from the text/graphics using a ruler. This manual process is tedious and time consuming.
Data Source
AI summary
A method and apparatus for calculating a log MAR value for a reading acuity test, including the steps of displaying words on a first computer monitor, where the words will be read aloud by a person taking the test; displaying the words on a second computer monitor, where words will be observable by a person administering the test, where the administrator can select words which are incorrectly read using a pointing device; measuring the amount of time the first person takes to read the words; calculating the reading rate based upon both the words correctly and those read incorrectly; measuring the distance between the first person and the monitor; and, calculating the log MAR value based upon the distance, the font size and the reading rate.