Optimal model-based sensorless adaptive optics for epifluorescence microscopy

Abstract

We report on a universal sample-independent sensorless adaptive optics method, based on modal optimization of the second moment of the fluorescence emission from a point-like excitation. Our method employs a sample-independent precalibration, performed only once for the particular system, to establish the direct relation between the image quality and the aberration. The method is potentially applicable to any form of microscopy with epifluorescence detection, including the practically important case of incoherent fluorescence emission from a three dimensional object, through minor hardware modifications. We have applied the technique successfully to a widefield epifluorescence microscope and to a multiaperture confocal microscope.

Anisoplanatic adaptive optics in parallelized laser scanning microscopy

“…Isoplanatic adaptive optics was performed on a set of 24 gradient orthogonal [12] mirror modes. Correction time for a single image was approximately 5s.…”

“…A second telescope (7,8) conjugates the DM to the back aperture of the objective (9). Fluorescence light propagates the opposite direction, is descanned by the DM, filtered by a dichroic and emission filter set (10) and focused by a short focal tube lens (11) on the camera detector (12). A 1.5× telescope of two achromatic doublets of focal lengths 100 and 150mm respectively was used to conjugate the surface of the SLM to the surface of the DM.…”

“…For the results presented in this paper, we use the optimal model based method previously developed by the authors It is crucial to notice that all correction patterns are defined over the full size of the pupil, therefore exploiting the full resolution of the corrector. [12]. For this specific optimization procedure, the second moment of the average spatial distribution of the camera images of spots is used as a metric.…”

“…A second telescope(7,8) conjugates the DM to the back aperture of the objective(9). Fluorescence light propagates the opposite direction, is descanned by the DM, filtered by a dichroic and emission filter set(10) and focused by a short focal tube lens(11) on the camera detector(12).…”

Scattering Compensation for Deep Brain Microscopy: The Long Road to Get Proper Images

“…Sensorless methods have the main advantage that it is not necessary to introduce neither additional optical components in the detection part of the microscope, nor guide star sources in the sample. On the contrary, these methods typically suffer from longer optimization times compared to wavefront sensing [19], requiring the acquisition of a minimum of N + 1 images in order to achieve optimal correction with an adaptive element with N actuators [6,39,40], small volumes of proper correction [26], the introduction of fluorescent beads in the scattering medium [27] and may require serial images acquisition [28]. Interestingly, to speed up the optimization process, Galwaduge et al [7] iteratively determined the correction across the whole pupil instead of working on a subset of pixels.…”