Electronic speckle pattern interferometry and digital holographic interferometry with microbolometer arrays at 10.6...

Area of Science:

• Optics and Photonics
• Metrology
• Experimental Physics

Background:

• Traditional interferometry techniques face limitations in measurement range and sensitivity to environmental noise.
• Infrared wavelengths offer potential advantages for extending interferometric capabilities.

Purpose of the Study:

• To investigate the application of long infrared wavelengths in electronic speckle pattern interferometry (ESPI) and digital holographic interferometry (DHI).
• To explore the benefits of extended measurement range and reduced sensitivity to perturbations.
• To analyze the impact of long wavelengths on object surface reflection characteristics.

Main Methods:

• Utilized a CO(2) laser emitting at 10.6 μm for infrared interferometry.
• Employed microbolometer arrays for infrared detection.
• Developed experimental configurations for phase-shifting ESPI (in-plane and out-of-plane) and lensless DHI.
• Performed rotation measurements on a solid object.

Main Results:

• Demonstrated the feasibility of ESPI and DHI at long infrared wavelengths (10.6 μm).
• Showcased phase-shifting ESPI for both in-plane and out-of-plane measurements.
• Successfully implemented lensless DHI for rotation measurements.
• Observed and discussed the altered reflection behavior of object surfaces at these wavelengths.

Conclusions:

• Long infrared wavelengths are effective for enhancing ESPI and DHI.
• These long-wavelength interferometric techniques offer extended measurement ranges and improved robustness against external perturbations.
• The study validates the use of 10.6 μm CO(2) laser-based interferometry for precise metrology applications.