Fig. 1

Fig. 1

a Schematic of AO 2PFM with Gaussian (yellow path) or Bessel (red path) focus scanning. Bessel path has an additional lens (L1) and transmissive annular mask (Mask) placed after the first spatial light modulator (SLM1). Lens pairs (L2–L3, L4–L5, L6–L7) conjugate Mask, X and Y galvanometers (Galvos), another SLM (SLM2), and microscope objective back pupil plane (dashed blue lines). In the Bessel path, SLM1 is conjugated to the objective focal plane (dashed black lines). SLM1: generation and focal-plane aberration correction of Bessel focus; SLM2: indirect wavefront measurement and aberration correction of Gaussian focus. b Axial images and c signal profiles of a 0.1-µm-diameter fluorescent bead before and after system aberration correction of Gaussian focus. Inset in c: pupil-plane corrective wavefront on SLM2. d Axial images and e signal profiles of a 0.1-µm-diameter fluorescent bead imaged by a Bessel focus without AO (binary phase mask on SLM1 only), with pupil-plane AO (binary phase mask on SLM1, pupil corrective pattern on SLM2), and with focal-plane AO (focal corrective pattern on SLM1 only), respectively. Insets in e: phase patterns on SLM1 and SLM2. Dashed circles in Pupil AO inset: footprint of annular illumination on SLM2. f Flowchart showing (top) the computation procedure and (bottom) numerical validation of the focal-plane wavefront pattern for aberration-corrected Bessel focus. Top: Pupil-plane corrective pattern within the annular mask is propagated to focal plane via Fourier transform. The resulting phase pattern serves as the aberration-correcting focal-plane phase pattern on SLM1. Bottom: Inverse Fourier transform of the focal-plane phase pattern replicates the annular amplitude and corrective phase patterns on the pupil plane. Concentric dashed circles: annular mask footprints. AU arbitrary unit. Source data are available as a source data file.