Lens-Free Wide-Field Super-Resolution Imaging (Case No. 2010-598)

Summary

Researchers at UCLA have developed a lens-free, wide-field super-resolution imaging platform that uses a scanned illumination aperture and computational reconstruction to overcome the pixel size limit and achieve high-resolution imaging across large fields of view. The system captures multiple low-resolution holograms under shifted illumination and uses sub-pixel registration and algorithmic reconstruction to produce a high-resolution final image.

Background

Traditional optical microscopy systems often face a trade-off between field of view (FOV) and spatial resolution. When placing the sample very close to the sensor (on-chip holography), pixel size of the image sensor becomes a limiting factor, preventing resolution enhancement. At the same time, using magnification optics reduces the FOV and introduces complexity. To bring super-resolution imaging to compact, wide-area, lens-free systems, novel approaches are needed to circumvent the pixel-size constraint computationally, while maintaining large fields of view.

Innovation

  • The system uses a scannable illumination aperture (e.g. a LED or laser source through a small aperture) that is raster scanned over multiple positions relative to the sample.

  • Each scan position yields a lower-resolution hologram captured directly on the sensor, without lenses.

  • Because the illumination shift corresponds to sub-pixel shifts at the sensor plane, the method recovers high spatial frequency information by combining these multiple holograms (i.e. a super-resolution reconstruction algorithm) to surpass the native sensor pixel limit.

  • The algorithm includes self-calibration: the system does not require external knowledge of the scanning step. The shifts are inferred during reconstruction from raw holograms, simplifying hardware alignment and making the system robust.

  • Because the illumination is partially coherent and from a relatively large aperture, the system suppresses speckle noise and interference artifacts compared to coherent-holography approaches.

  • The reconstruction yields a numerical aperture ~0.5, enabling ~0.6 μm spatial resolution at visible wavelengths, while retaining a large imaging FOV (e.g. ~24 mm²) corresponding to the full detector area. 

Advantages

  • Achieves high spatial resolution (sub-micron) even when limited by sensor pixel size.

  • Maintains large field of view: FOV is equal to the active area of the detector, rather than reduced by magnification optics.

  • Hardware simplicity: no refractive optics, lenses, or complex alignments required.

  • Self-calibrating shift estimation reduces mechanical complexity and calibration burden.

  • Reduced noise artifacts due to partially coherent illumination and large aperture usage.

  • Scalable: larger sensor chips yield proportionally larger FOV at high resolution.

Potential Applications

  • On-chip microscopy for cell biology: imaging live cells, pathogens, or microstructures over large fields.

  • Portable diagnostic imaging systems, e.g. point-of-care microscopy.

  • High-throughput screening platforms requiring wide-area imaging with sub-micron details.

  • Environmental imaging (microplastics, particulates, organisms) in situ.

  • Lab-on-chip devices combining imaging and microfluidics.

  • Low-cost imaging devices for resource-limited settings (e.g. in field diagnostics).

Patent / Application

US 8,866,063 B2 — Lens-Free Wide-Field Super-Resolution Imaging Device
Lens-Free Wide-Field Super-Resolution Imaging Device (US8866063B2) Google Patents

Publications by the Inventors (Related Work)

  • Bishara, W.; Rotella, C.; Ozcan, A. “Lens-free, pixel super-resolution, wide-field on-chip microscopy via self-assembled masks.” Optics Express 18(11): 11181-11191 (2010). DOI: 10.1364/OE.18.011181 — describes foundational techniques in mask scanning and computational super-resolution for lens-free imaging.

Patent Information:
For More Information:
Nikolaus Traitler
Business Development Officer (BDO)
nick.traitler@tdg.ucla.edu
Inventors:
Aydogan Ozcan
Waheb Bishara