Phase calculation of smooth surface with multi-reflectivity based on phase measurement deflectometry.

Area of Science:

• Optical Metrology
• Precision Engineering
• Surface Inspection

Background:

• Complex objects with high reflectivity are increasingly common due to advancements in precision machining.
• Phase Measurement Deflectometry (PMD) is a non-contact technique for inspecting reflective surfaces, offering high accuracy and speed.
• Existing PMD methods struggle with surfaces of varying reflectivity, leading to errors caused by fringe contrast differences.

Purpose of the Study:

• To develop an adaptive fringe generation method for Phase Measurement Deflectometry (PMD).
• To enable accurate simultaneous detection of multiple objects with varying reflectivity.
• To overcome limitations of traditional PMD in handling heterogeneous reflective surfaces.

Main Methods:

• Proposed an adaptive fringe generation technique for PMD systems.
• Developed methods to adjust fringe intensity based on surface reflectivity.
• Implemented light compensation at reflectivity boundaries to improve fringe visibility.

Main Results:

• Successfully achieved accurate phase calculation for multiple reflective surfaces.
• Demonstrated improved fringe contrast across areas with significant reflectivity variations.
• Validated the adaptive method's capability to maintain accuracy with heterogeneous surfaces.

Conclusions:

• The proposed adaptive fringe generation method enhances PMD for complex, multi-reflective objects.
• This technique overcomes the challenge of varying fringe contrast in traditional PMD.
• Enables robust and accurate non-contact inspection of diverse reflective surfaces.