Optical Tomography of Polymeric Microsphere Layers Using Confocal Raman Microscopy.

Area of Science:

• Materials Science
• Optical Microscopy
• Spectroscopy

Background:

• Confocal Raman microscopy enables 3D structural and chemical analysis of transparent objects.
• Depth profiling accuracy in Raman microscopy is challenged by sample size and environmental optical effects.
• Quantitative tomography of 3D objects requires precise dimension determination.

Purpose of the Study:

• To investigate optical effects at the interface between polymer spheres and substrates in Raman depth profiling.
• To develop a method for improving the accuracy of 3D object dimension measurements obtained via Raman depth profiling.
• To provide a deeper understanding of factors influencing Raman depth profile interpretation.

Main Methods:

• Utilized ray- and wave-optical simulations to model optical effects.
• Performed experimental studies on polymer spheres and various substrates.
• Derived a correction factor for Raman depth profile measurements.

Main Results:

• Demonstrated that sample size and surrounding objects significantly impact Raman depth profile interpretation.
• Validated simulation results with experimental data.
• Developed a correction factor to enhance the accuracy of 3D object dimension determination.

Conclusions:

• Accurate quantitative tomography using confocal Raman microscopy requires accounting for optical interface effects.
• The derived correction factor improves the precision of 3D object dimension measurements.
• Careful consideration of instrumental configuration and sample environment is crucial for reliable Raman depth profiling.