Sample Stage Positioning With Imaging Feedback During Translation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing characterization tools face inefficiencies in inspecting targets across a sample due to time-consuming stage settling, image acquisition, and image processing, leading to substantial positioning errors based on single image calculations.
Innovation Solution
A sample positioning system and method using a sample as a large-scale encoder, employing closed-loop feedback with imaging detectors to adjust sample stage positioning in real-time, allowing for faster navigation and higher accuracy by relying on imaging detector resolution rather than external calibrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional alignment methods using physical fixtures and manual measurement are used, then setup time and labor costs are high, but positioning precision and repeatability are insufficient
Solution Approach 1:
The patent replaces manual mechanical alignment methods with an automated optical measurement system. The system uses a laser tracker to automatically capture coordinate data of workpiece features, eliminating the need for physical alignment fixtures and manual measurement tools. This substitution enables high-precision positioning (micrometer-level accuracy) while dramatically reducing setup time, as the laser tracker can rapidly collect data points without human intervention for each measurement.
Solution Approach 2:
The patent creates a digital copy (point cloud model) of the workpiece geometry by capturing numerous coordinate points with the laser tracker. This digital replica allows for precise virtual measurement and alignment calculations to be performed on the computer, replacing time-consuming physical measurement and adjustment processes. The point cloud model serves as a faithful copy that preserves all geometric features needed for positioning while enabling faster, more accurate analysis.
2Measurement precision
If complex alignment procedures with multiple measurement steps are used, then positioning accuracy may be improved, but process complexity and potential for error increase
Solution Approach 1:
The system performs self-alignment through automated coordinate data processing. The laser tracker automatically captures points on reference features and workpiece features, and the computer executes algorithms that automatically calculate optimal positioning parameters without requiring operator intervention for each measurement step. This self-service capability reduces procedural complexity while maintaining high accuracy, as the system autonomously handles the complex calculations and decision-making that would otherwise require skilled operators following complex procedures.
Solution Approach 2:
The system incorporates feedback loops where the laser tracker continuously monitors workpiece position and orientation, and the computer adjusts alignment parameters based on measured deviations from target positions. This closed-loop feedback mechanism automatically compensates for positioning errors and ensures high alignment accuracy without requiring complex manual adjustment procedures. The real-time feedback enables the system to self-correct and verify alignment precision throughout the positioning process.
Data Source
Figure 1A
Figure 1B
Figure 1C
AI summary
A sample positioning system is disclosed. The system may include an imaging detector. The system may further include a controller communicatively coupled to the imaging detector and a sample stage, the controller including one or more processors configured to execute program instructions causing the one or more processors to: receive a current position of a field of view of the imaging detector; receive a target position of the sample; receive locations of reference features along a path; direct the sample stage to translate the sample along the path; direct the imaging detector to capture images of the reference features along the path; determine positioning errors of the sample stage along the path based on the images of the reference features; and adjust at least one of a velocity of the sample stage or the path to the target location based on the positioning errors during translation.