Ultra-compact 3D-printed wide-angle cameras realized by multi-aperture freeform optical design

Area of Science:

• Optics and Photonics
• Advanced Manufacturing
• Imaging Systems

Background:

• Achieving ultra-large fields of view (FOV), large image sizes, and compact form factors simultaneously presents significant challenges in optical lens design.
• Integrating advanced imaging capabilities into limited spaces requires innovative solutions for lens fabrication and design.

Purpose of the Study:

• To present concepts, correction methods, and realizations for freeform multi-aperture wide-angle cameras.
• To demonstrate the fabrication of 180° x 360° cameras with a flat, micrometer-scale form factor using femtosecond direct laser writing (fsDLW).

Main Methods:

• Utilizing femtosecond direct laser writing (fsDLW) for 3D printing of freeform multi-aperture camera designs.
• Employing highly tilted and decentered non-rotational lens shapes and catadioptric elements for FOV mapping.
• Implementing confocal measurements and iterative fsDLW for precise freeform surface correction.
• Developing digital distortion correction and image stitching algorithms.

Main Results:

• Successful fabrication of freeform multi-aperture wide-angle cameras with a 180° x 360° FOV and a flat form factor.
• Demonstrated ability to map the extensive FOV onto a flat sensor using Scheimpflug principles with freeform and catadioptric elements.
• Validated methods for measuring and correcting freeform surfaces with extreme normal angles.

Conclusions:

• Freeform multi-aperture designs fabricated by fsDLW offer a viable solution for compact, ultra-wide-angle imaging.
• The presented fabrication and correction techniques enable the realization of advanced wide-angle camera systems.
• This technology facilitates extensive information capture in space-limited environments.