Super achromatic wide-angle quarter-wave plates using multi-twist retarders

Area of Science:

• Optics and Photonics
• Materials Science
• Display Technology

Background:

• Quarter-wave plates (QWPs) are essential for color uniformity and image resolution in virtual reality (VR) and augmented reality (AR) displays.
• Existing achromatic wide-angle QWPs are often complex and have limited performance.
• Previous multi-twist retarder (MTR) QWPs showed promise but struggled with polarization control in blue-violet light for LED-based systems.

Purpose of the Study:

• To theoretically investigate a new type of MTR QWP with enhanced achromaticity and wide-angle performance.
• To address the limitations of previous MTR QWPs in blue-violet light spectrum.
• To enable precise polarization control for next-generation AR/VR headsets.

Main Methods:

• Theoretical investigation of a novel MTR QWP design.
• Analysis of achromaticity across the violet to red spectrum.
• Evaluation of viewing angle performance up to ±45°.
• Assessment of reflection luminance leakage.

Main Results:

• Achieved super achromaticity from violet to red with an average ellipticity of 43°.
• Maintained a wide viewing angle up to ±45° for precise polarization control.
• Reported low average reflection luminance leakage of 0.15% and maximum leakage of 0.23%.

Conclusions:

• The proposed MTR QWP offers significant improvements in achromaticity and wide-angle performance for AR/VR displays.
• This design enables precise polarization control within the field-of-view of current headsets.
• The low leakage characteristics make it a promising component for reducing polarization issues and enhancing image resolution in future displays.