Optical Lens Surface Angle Measurement Using Vignetting Field Stop
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for measuring optical lens surfaces, particularly aspherical lenses, require complex imaging optics and are not efficient for rapid measurement of multiple lens surfaces.
Innovation Solution
A method using an extended light source and a vignetting field stop to generate an optical measuring beam, which is reflected off multiple lens surfaces and detected as separate light spots on a spatially resolving optical detector, allowing for simultaneous measurement of at least two lens surfaces without complex optics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If complex imaging optics are used to measure multiple lens surfaces, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent segments the measurement of multiple lens surfaces by using separate aperture stops for each surface, allowing independent optimization of the measurement beam path for each surface while using a single detector. This segmentation enables precise measurement of multiple surfaces without requiring complex imaging optics for each surface individually.
Solution Approach 2:
The patent creates a universal measurement system where a single optical detector serves multiple functions by detecting light spots from different lens surfaces simultaneously. The system uses one detector to measure multiple lens surfaces by varying the aperture stop positions and sizes, eliminating the need for separate imaging optics for each surface.
2Measurement precision
If separate imaging optics are used for each lens surface, then measurement precision is improved, but productivity decreases
Solution Approach 1:
The patent merges the measurement of multiple lens surfaces into a single simultaneous operation. By using different aperture stops that can be positioned and sized independently, the system captures light spots from multiple lens surfaces at the same time on a single detector, dramatically improving productivity compared to sequential measurement with separate imaging optics.
Solution Approach 2:
The patent employs preliminary action by pre-positioning and pre-sizing the aperture stops before measurement. The aperture stops are configured in advance with specific positions and diameters optimized for each lens surface, allowing the measurement system to immediately capture multiple surfaces without requiring real-time optical adjustment during the measurement process.
3Device complexity
If a single aperture stop is used for all lens surfaces, then device complexity is reduced, but measurement precision deteriorates
Solution Approach 1:
The patent introduces dynamics by making the aperture stop parameters (position and diameter) variable rather than fixed. The system can dynamically adjust the aperture stop configuration for each lens surface measurement, allowing optimal measurement conditions for each specific surface while maintaining the simplicity of a single stop mechanism. This dynamic adjustment preserves measurement precision without requiring complex multi-stop 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 and rapid measurement of the angles of multiple lens surfaces relative to the optical axis, facilitating the detection of vertex offsets and axis tilts in aspherical lenses, with improved accuracy and reduced complexity compared to prior methods.
Implementation Method 1
an optical measuring beam is generated with an extended light source, collimated via an optical arrangement, directed onto a first lens surface of an optical lens arrangement that is to be measured and detected using at least one spatially resolving optical detector after reflection on the first lens surface to be measured
Data Source
AI summary
In a method for measuring optical lens surfaces, a measuring beam is generated by an extended light source, collimated via an optical arrangement, and detected using an optical detector after reflection on a lens surface to be measured. An aperture delimiting the measuring beam is inserted between the light source and the optical detector and acts as a vignetting field stop. The field stop is imaged onto the optical detector out of focus as a first light spot by the measuring beam after reflection on a first lens surface. The optical detector simultaneously also detects at least a second light spot obtained by reflection of the measuring beam on a second lens surface. An angle of each lens surface with respect to the optical axis of the measuring beam can be simultaneously determined for both lens surfaces from the intensity distribution of the two light spots.