Parasitic reflection elimination based on adaptive fringes via multi-scale parallel single-pixel imaging in phase...

Area of Science:

• Optical Engineering
• Metrology

Background:

• Deflectometry optical testing often suffers from ghost fringes, which are spurious signals that degrade measurement accuracy.
• These ghost fringes arise from reflections on both front and rear surfaces of optical components, complicating analysis.

Purpose of the Study:

• To introduce a novel method for adaptively modifying screen displays to eliminate ghost fringes in deflectometry.
• To enhance the accuracy and reliability of optical surface testing.

Main Methods:

• Multi-scale Fourier parallel single-pixel imaging (MS-PSI) is used to precisely label reflection areas on the screen.
• Fringe patterns are selectively cast onto labeled regions, avoiding the entire screen for improved front surface data acquisition.
• Classic spatial filtering is applied to remove residual mixed signals from the central region.

Main Results:

• The proposed method successfully eliminates ghost fringes observed in deflectometry.
• Experimental verification using plano-convex and plano-concave lenses demonstrates the method's effectiveness.
• The final surface reconstruction accuracy achieved is in the sub-micron range.

Conclusions:

• Adaptive screen display modification offers a robust solution for ghost fringe suppression in deflectometry.
• The method significantly enhances the precision of optical surface metrology.
• This technique is validated for its high accuracy in characterizing optical components.