Reduction of spherical-aberration impact in microscopy by wavefront coding

Abstract

In modern high-NA optical scanning instruments, like scanning microscopes, the refractive-index mismatch between the sample and the immersion medium introduces a significant amount of spherical aberration when imaging deep inside the specimen, spreading out the impulse response. Since such aberration depends on the focalization depth, it is not possible to achieve a static global compensation for the whole 3D sample in scanning microscopy. Therefore a depth-variant impulse response is generated. Consequently, the design of pupil elements that increase the tolerance to this aberration is of great interest. In this paper we report a hybrid technique that provides a focal spot that remains almost invariant in the depth-scanning processing of thick samples. This invariance allows the application of 3D deconvolution techniques to that provide an improved recovery of the specimen structure when imaging thick samples.

A wide-FoV athermalized infrared imaging system with a two-element lens

“…This technique firstly was used to extend field depth of a microscope [20] and then researchers explored this technique to athermalize infrared imaging systems [5,15]. This technique mainly includes two stages of optical coding and digital decoding.…”

A Wide-FoV Athermalized Infrared Imaging System with a Two-Piece Lens

“…This technique firstly was used to extend field depth of a microscope [8] and then researchers explored this technique athermalized an infrared imaging systems [5] . This technique mainly includes two stages of optical coding and digital decoding.…”

Spherical Aberration of Point Spread Function with Asymmetric Pupil Mask

“…The spherical aberration can also be explained by saying that the deviation of the principal surface from its ideal shape causes the focal length to slightly vary with the radius of zone of the aperture. There has been a significant number of studies involving diffractive monochromatic aberrations with different aperture systems and techniques [11][12][13].…”