Comparative analysis of doublets versus single-layer diffractive optical elements in eyepiece or magnifier design

Area of Science:

• Optical Engineering
• Optics and Photonics

Background:

• Eyepiece design is critical for optical system performance.
• Eye clearance significantly impacts optical element usability and performance.
• Traditional doublet designs face limitations with increasing eye clearance requirements.

Purpose of the Study:

• To quantify the impact of eye clearance on eyepiece performance.
• To compare doublets and diffractive optical elements (DOEs) on aspheric substrates.
• To determine the optimal eye clearance for different eyepiece technologies.

Main Methods:

• Designed and optimized cemented on-axis doublets and single-layer DOEs.
• Evaluated performance across four eye clearance values (17-26 mm).
• Compared key optical aberrations including axial/lateral color, spherical aberration, coma, astigmatism, field curvature, and distortion.

Main Results:

• Single-layer DOEs supported approximately 80% of effective focal length in eye clearance.
• Doublets met desired specifications at approximately 65% of effective focal length.
• Performance metrics were evaluated for photopic wavelengths (513-608 nm) and a 40-degree field of view.

Conclusions:

• Diffractive optical elements demonstrate superior eye clearance capabilities over doublets.
• DOEs provide a viable solution for eyepieces requiring extended eye relief.
• Design choices in eyepiece technology directly influence performance under varying eye clearance conditions.