Variable Optical Power Refraction Apparatus for High-Precision Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for measuring subjective ocular refraction are limited by discontinuous variations in optical power, leading to imprecise measurements due to the step size of trial lenses and the subject's ability to detect differences in optotypes, with existing complex systems suffering from chromatic aberrations and low effectiveness.
Innovation Solution
An apparatus with a viewing device and refractive optical system that varies cylindrical and spherical optical power in smaller steps, using a two-dimensional array of pixels and micro-lenses or micro-apertures, along with additional means such as complementary refractive optical components, to generate images with continuous or incremental power variations, allowing for precise refraction measurement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional trial lenses with fixed step sizes are used, then the device complexity is low, but the measurement precision is limited by the minimum step size of 0.25 diopters
Solution Approach 1:
The optical system is segmented into multiple independent lens elements (first lens, second lens, third lens) with different optical powers. By selectively combining these segmented lens elements, the system achieves variable optical power in small increments without requiring a completely new apparatus design.
Solution Approach 2:
The system transitions from static fixed-power trial lenses to a dynamic configuration where lens elements can be selectively added or removed. This allows the total optical power to be dynamically adjusted in small steps by changing the combination of active lens elements rather than using a single fixed-power lens.
2Measurement precision
If trial lenses with smaller step sizes are used, then the measurement precision improves, but the device complexity increases due to needing multiple lenses and lens changes
Solution Approach 1:
Multiple lens elements with different optical powers are merged into a single optical path. The first lens, second lens, and third lens can be combined in various configurations to achieve the desired optical power, eliminating the need for physical lens changes while maintaining measurement precision.
Solution Approach 2:
The system enables continuous adjustment of optical power by selectively activating different lens element combinations. This eliminates the discontinuous lens changes required in conventional systems, allowing smooth transitions between different optical power levels for more accurate measurements.
3Measurement precision
If complex apparatus with continuous power variation are used, then the measurement precision improves, but the device complexity and chromatic aberrations increase
Solution Approach 1:
Instead of using a single complex continuous-power lens, the system creates multiple discrete lens elements that approximate continuous power variation. Each lens element can be optimized individually, and their combinations replicate the effect of continuous adjustment without the chromatic aberrations inherent in complex continuous-power systems.
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 precise measurement of subjective ocular refraction with smaller step sizes or continuous variations, improving measurement accuracy beyond conventional methods without the need for complex equipment, by generating optical power differences smaller than the minimum step size of traditional trial lenses.
Implementation Method 1
a refractive optical system placed between an eye of an observer and the viewing device, the refractive optical system having a cylindrical and/or spherical optical power that may be varied
Implementation Method 2
a two-dimensional array of pixels and a two-dimensional array of micro-lenses or of micro-apertures that is placed between the electronic screen and the refractive optical system
Data Source
AI summary
Disclosed is an apparatus for measuring subjective ocular refraction including a display device configured to display a least one optotype and a refractive optical system arranged between an eye of a viewer and the display device, the refractive optical system having an optical power that can be varied according to a determined minimum step. The display device further includes a unit for varying optical power designed to generate a variation in the spherical and/or cylindrical optical power, such that the display device and the refractive optical system form a first image of the optotype with a first total optical power and, respectively, a second image of the optotype with a second total optical power, the variation in optical power between the first total optical power and the second total optical power being less than the determined minimum step.