Arbitrarily high focal depth with finite apertures

Area of Science:

• Optical Engineering
• Superresolution Imaging
• Diffractive Optics

Background:

• Achieving extended focal depth in optical systems with finite apertures is a significant challenge.
• Superresolution techniques typically focus on improving lateral resolution, not axial depth of field.
• Sensitivity to aberrations like spherical aberration limits the performance of conventional optical designs.

Purpose of the Study:

• To modify the concept of superresolution for extending focal depth.
• To design a novel apodizer capable of producing arbitrarily high depth of focus.
• To investigate the apodizer's ability to reduce sensitivity to spherical aberration and provide a method for evaluating light throughput.

Main Methods:

• Utilized Legendre polynomials for the design of a novel apodizer.
• The apodizer was designed to manipulate the optical field for extended focal depth.
• Developed a formula to quantify the light throughput of the designed apodizer.

Main Results:

• Demonstrated the design of an apodizer that provides arbitrarily extended depth of focus with a finite aperture.
• Showcased the apodizer's capability to arbitrarily reduce sensitivity to spherical aberration.
• Derived a formula for evaluating the light throughput, a key performance metric affected by the apodizer.

Conclusions:

• The proposed apodizer design offers a powerful method for enhancing depth of field in optical systems.
• This approach provides a trade-off between extended focal depth/reduced aberration sensitivity and light throughput.
• The derived formula is crucial for practical implementation, enabling the assessment of light efficiency for specific applications.