Optometry Apparatus Diopter Adjustment Minimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optometry apparatuses face challenges in minimizing the movement range of diopter adjustment mechanisms while preventing aberrations caused by astigmatism correction, which affects the clarity of the target presented to the examinee's eye.
Innovation Solution
An optometry apparatus with a target projecting optical system that includes an objective lens, a relay lens with its front focal point aligned with the anterior segment's approximate conjugate point, a plus-power lens with refractive power set for the fundus, and astigmatism correction elements between the relay and plus-power lenses to minimize diopter movement and correct astigmatism, ensuring a clear and high-resolution target presentation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the moving amount of diopter movement means is reduced, then the apparatus size is minimized, but the target may become affected by aberration of astigmatism correction means
Solution Approach 1:
The patent introduces a specific optical configuration with relay lenses positioned at conjugate points as intermediary elements between the objective lens and astigmatism correction means. This intermediary optical system transfers images while maintaining minimal movement requirements and reducing aberration effects on the target presentation.
Solution Approach 2:
The patent optimizes specific optical parameters including positioning relay lenses at approximate conjugate points of the anterior segment and fundus, and setting the refractive power of the plus-power lens so that its front focal point coincides with the approximate conjugate point of the fundus. These parameter optimizations enable minimal diopter movement while preventing aberration.
2Measurement precision
If the target is presented clearly to the examinee's eye, then image quality is improved, but the moving amount of diopter movement means increases
Solution Approach 1:
The patent replaces a mechanically complex diopter adjustment system with an optimized optical configuration using relay lenses at conjugate points. This substitution maintains high image quality for clear target presentation while significantly reducing the required mechanical movement distance of the diopter adjustment mechanism.
3Measurement precision
If astigmatism correction is performed, then visual accuracy is improved, but the target becomes affected by aberration
Solution Approach 1:
The relay lens system positioned at conjugate points acts as an intermediary that transfers the target image through the astigmatism correction means to the fundus. This intermediary configuration allows astigmatism correction to be performed while the target image itself remains unaffected by the aberrations generated during the correction process.
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 solution allows for reduced diopter movement range and minimizes aberrations, enabling clear and high-resolution target presentation to the examinee's eye by optimizing the alignment and refractive powers of the lenses, maintaining image clarity and resolution during diopter adjustments and astigmatism corrections.
Implementation Method 1
a relay lens arranged so that a front focal point of the relay lens coincides with an approximate conjugate point of an anterior segment of the examinee's eye
Implementation Method 2
a plus-power lens arranged at the approximate conjugate point of the anterior segment with respect to the positioned objective lens, the plus-power lens having refractive power determined so that a front focal point of the plus-power lens coincides with an approximate conjugate point of the fundus
Implementation Method 3
an astigmatism correction optical element arranged between the relay lens and the plus-power lens, for correcting astigmatism of the examinee's eye
Data Source
Figure 1
Figure 2
AI summary
An optometry apparatus comprising: a target projecting optical system (10) adapted for diopter movement, for projecting a target (1) onto a fundus of an examinee's eye (E) to form an image of the target on the fundus, wherein the target projecting optical system including: an objective lens (2) to be positioned at the front of the examinee's eye; a relay lens (6) arranged so that a front focal point of the relay lens coincides with an approximate conjugate point of an anterior segment of the examinee's eye with respect to the objective lens positioned at the front of the examinee's eye; a plus-power lens (3) arranged at the approximate conjugate point of the anterior segment with respect to the positioned objective lens, the plus-power lens having refractive power determined so that a front focal point of the plus-power lens coincides with an approximate conjugate point of the fundus with respect to the positioned objective lens; and an astigmatism correction optical element (4, 5) arranged between the relay lens and the plus-power lens, for correcting astigmatism of the examinee's eye.