Diffractive Refractometer Based on Scalar Theory

Area of Science:

• Materials Science
• Optics
• Photonics

Background:

• Optical ellipsometry is a standard method for refractive index measurement but is highly sensitive to sample structure and requires specialized expertise.
• Existing methods for refractive index determination often demand complex equipment and theoretical modeling, limiting accessibility.

Purpose of the Study:

• To develop a simple and accessible diffractive method for measuring the refractive index of homogenous solid thin films.
• To provide a cost-effective and user-friendly alternative to traditional optical characterization techniques.

Main Methods:

• Structuring the material surface with a diffraction grating profile.
• Utilizing a scalar theory-based diffraction model incorporating measured topography and diffraction efficiency.
• Estimating the refractive index by analyzing the diffraction pattern.

Main Results:

• Successfully estimated the refractive index of a soft-moldable material over a wide wavelength range.
• Demonstrated the method's effectiveness without requiring specialized expertise or equipment.
• Validated the simplicity and accessibility of the proposed diffractive technique.

Conclusions:

• The proposed diffractive method offers a straightforward and widely accessible approach for optical characterization of thin films.
• This technique has significant potential for applications in material science and photonics where ease of use and cost-effectiveness are crucial.