Object Positioning via Dual Illumination Parallax
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining the position of an object parallel to the optical axis of an optical device are either inaccurate or require complex and expensive interferometric techniques.
Innovation Solution
A method involving illumination of the object from two different directions, acquiring images, and determining the distance between imaging locations to calculate the object's position relative to the optical axis, allowing for rapid and accurate positioning without mechanical displacement of the object.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If sharpness-based positioning techniques are used to determine z position, then the method is simple to implement, but the measurement precision is limited and inaccurate
Solution Approach 1:
The patent replaces the mechanical/physical sharpness assessment method with an optical measurement system. By using illumination from multiple directions and measuring imaging location displacements, the system achieves accurate z-position determination without relying on subjective or limited sharpness evaluation, thus substituting a mechanical assessment approach with a more precise optical measurement system.
Solution Approach 2:
The patent introduces an intermediary measurement approach by using imaging location displacement as an intermediate parameter to determine z position. Instead of directly measuring sharpness, the system uses the displacement of imaging locations under different illumination directions as an intermediary indicator, which can be measured with high precision and then correlated to z-position through calibration or calculation.
2Measurement precision
If interferometric techniques are used to determine z position, then the measurement precision is high, but the device complexity and cost increase
Solution Approach 1:
The patent extracts and utilizes only the necessary functional elements for z-position measurement without requiring the full interferometric system. By taking out the essential measurement principle (optical path difference detection) and implementing it through simpler illumination and imaging location detection, the system achieves interferometric-level precision without the complexity of complete interferometric instrumentation.
Solution Approach 2:
The patent creates a simplified optical measurement model that copies the essential measurement principle of interferometry without replicating its full complexity. By using multiple illumination directions and measuring imaging location displacements, the system replicates the interference-based measurement capability through a different but functionally equivalent optical arrangement, achieving similar precision with simpler components.
3Measurement precision
If multiple images at different reference positions are acquired to determine position, then the position can be determined, but the time required for position determination increases
Solution Approach 1:
The patent transitions from measuring position in one dimension (acquiring multiple images at different z-positions) to measuring position by exploiting another dimension (illumination direction angles). By illuminating from multiple directions and measuring displacements in the image plane, the system determines z-position without needing to physically move the object through multiple reference positions, thus saving time while maintaining accuracy.
Solution Approach 2:
The patent performs preliminary calibration or establishes predetermined relationships between imaging location displacements and z-position. This preliminary action allows the system to determine z-position rapidly during operation by simply measuring displacements under different illumination directions, without needing to acquire multiple images at different reference positions each time, thus reducing measurement time while preserving accuracy.
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 efficient determination of the object's position, facilitating high-quality imaging by focusing the object quickly and reliably within the focal plane.
Implementation Method 1
illumination of the object from a first illumination direction and acquisition of a first image of the object during the illumination
Implementation Method 2
the imaging location of the object in a corresponding image may be displaced if the object does not lie in the focal plane of the optical device
Implementation Method 3
this effect may be interpreted by modified parallax in relation to the illumination direction
Data Source
AI summary
To determine a position of an object (100) parallel to the optical axis (120) of an optical device (1), the object (100) is illumined from a first illumination direction (210-1) and from a second illumination direction (210-2) and an image (230-1, 230-2) is acquired in each case. The position of the object (100) is determined based on a distance (250) between imaging locations of the object (220-1, 220-2) in the images (230-1, 230-2).