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Measuring the lens focal length by laser reflection-confocal technology
Jiamiao Yang1, Lirong Qiu, Weiqian Zhao
1Key Laboratory of Photoelectronic Imaging Technology and System, Ministry of Education of China, Opto-Electronic College, Beijing Institute of Technology, Beijing, China.
Applied Optics
|June 6, 2013
Summary
A new laser reflection-confocal focal-length measurement (LRCFM) method precisely determines lens focal length. This technique achieves high accuracy with minimal uncertainty, offering a superior alternative for optical metrology.
Area of Science:
- Optical Engineering
- Metrology
- Lens Measurement
Background:
- Accurate focal length measurement is critical in optical system design and manufacturing.
- Existing methods often face limitations in precision and susceptibility to environmental factors.
Purpose of the Study:
- To introduce a novel, high-accuracy method for measuring lens focal length.
- To demonstrate the enhanced precision and robustness of the proposed technique.
Main Methods:
- Utilizes laser reflection-confocal principles to identify lens focus and surface vertex.
- Employs peak points of confocal response curves for precise positioning.
- Incorporates conic fitting to mitigate environmental disturbances and system noise.
Main Results:
- Achieved a relative expanded uncertainty of less than 0.0015%.
- Demonstrated significantly enhanced measurement accuracy compared to existing methods.
- The method exhibits a concise structure and high precision.
Conclusions:
- Laser reflection-confocal focal-length measurement (LRCFM) is a feasible and highly accurate technique.
- LRCFM offers a robust solution for precise focal length determination in optical applications.
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