limiting factor to achieve highest resolution and large superresolved fields of view at the same time” [10]. The Gaussian envelope of STED intensity makes the resolution position dependent
that varies according to square root law. This particular application
highlights the need for high input power and uniform illumination. Given the above constraints, it is therefore necessary to have
an efficient photon management system that reshapes light by
utilizing as much photons from available laser sources.
In this work, we propose to uniformly illuminate and match the
profile of beam shaping elements and yet maintain high light efficiency by using the GPC method to create an efficient static input
beam shaping prior to intended dynamic beam modulation applications. The GPC method provides a straightforward phase to
intensity mapping using a simple 4f imaging setup and can be
considered as a generalization of Zernike's phase contrast microscopy technique applied to beam shaping and optical information
processing [11]. GPC has been used to generate speckle-free extended light patterns and has recently been combined with temporal focusing in rapidly reconfigurable two-photon optogenetics
to create neuron-shaped excitations [12]. Prior theoretical and
numerical predictions has been carried out to optimize and match
GPC light shaping for Gaussian laser profiles [13,14]. Although GPC
can be directly used for beam shaping in various applications it
can also help researchers that use other beam shaping methods by
improving light efficiency in their applications. The current work
examines this hybrid implementation where the GPC method is
used to pre-shape the input beam for optimal illumination of any
type of dynamic modulation element. For illustration, we demonstrate illumination of a spatial light modulator (SLM) encoded
with dynamic computer generated holograms. The SLM has been
chosen for this experiment due to its wide range of use in optical
trapping, microfabrication and photo-excitation. The performance
of the GPC-enhanced approach is compared to the traditional case
of a hard-truncated input beam for the same input laser power.
Reconfigurable spot arrays and extended light patterns serve as
intensity targets.