Volumetric HiLo microscopy employing an electrically tunable lens

Area of Science:

• Microscopy and Imaging Technologies
• Optical Physics
• Biomedical Engineering

Background:

• Electrically tunable lenses offer fast axial scanning in microscopy but introduce aberrations and resolution loss.
• Nonlinear voltage-to-displacement response complicates frame acquisition and depth-of-field management.

Purpose of the Study:

• To develop an adaptive microscope system overcoming the limitations of electrically tunable lenses for high-resolution volumetric imaging.
• To enable motion-free axial scanning with improved resolution and flexible depth-of-field control.

Main Methods:

• Implementation of an Adaptive-Lens-High-and-Low-frequency (AL-HiLo) microscope utilizing an electrically tunable lens.
• Employing speckle-patterned illumination to stabilize against lens-induced aberrations.
• Developing a posteriori depth-of-field adjustment for flexible scan compensation.

Main Results:

• Achieved an axial scanning range of 1 mm with an axial resolution of approximately 4 μm.
• Maintained sub-micron lateral resolution across the entire scanning range.
• Demonstrated proof-of-concept imaging in custom specimens and zebrafish embryos.

Conclusions:

• The AL-HiLo microscope effectively compensates for aberrations and nonlinearities of electrically tunable lenses.
• This adaptive approach enables precise volumetric measurements with high resolution and flexible scanning capabilities.
• The system shows promise for advanced biological imaging applications, such as studying gene expression in developing organisms.