Compact grating interferometer for producing photoresist gratings with incoherent light

Area of Science:

• Optics and Photonics
• Materials Science

Background:

• High-efficiency gratings are crucial for optical systems.
• Previous methods faced challenges in precision and stability.

Purpose of the Study:

• To develop a stable, compact achromatic interferometer.
• To produce high-quality 1200-lines/mm crossed-line photoresist gratings.
• To achieve high diffraction efficiency.

Main Methods:

• Utilized a mercury arc light source and a compact reflection system.
• Developed precise alignment procedures, including coplanar grating alignment using a Twyman-Green interferometer.
• Employed photoresist grating fabrication techniques.

Main Results:

• Successfully produced 1200-lines/mm crossed-line photoresist gratings.
• Achieved outstanding system stability.
• Attained first-order diffraction efficiency exceeding 20%.

Conclusions:

• The developed achromatic interferometer is effective for fabricating high-performance gratings.
• The system's stability and precision enable efficient grating production.
• The achieved diffraction efficiency meets demanding optical application requirements.