applications. However, the high intensity gain from the GPC-enhanced beam has major advantage for many applications. Fig. 4
clearly shows a significant increase in the intensity of the generated spot arrays when using GPC-enhanced readout. The 3
gain means that three times more intense spots can be holographically generated with a GPC-enhanced readout using the
same incident laser power. Alternatively, this enables a user to
generate an array with 3 more spots having the same intensities
as the fewer spots when reading out by a hard-truncated beam.
For example, the 40 spots created by GPC-enhanced readout in
Fig. 4 are still brighter than the 20 spots in the hard-truncated
case. This new functionality could have a large impact for various
applications, e.g. requiring multiple optical tweezers [3], multi-site
two-photon photolysis [6] and in parallel two-photon polymerization [8].
Another typical holographic application is the generation of
arbitrary extended intensity patterns. However, the inherent presence of speckles is one major drawback of this beam shaping
technique. A major cause of speckles in diffractively-generated
extended light patterns is the “randomly” oscillating phase distribution at the far-field reconstruction plane mainly caused by
cross-talk between adjacent output resolution elements due to the
optical convolution process with the point spread function (PSF) of
the system [19,20]. Considering that we get 4:3 rectangular output
with both GPC LS and hard truncation, the PSF for both will have a
2D sinc profile matching the 4:3 aspect ratio and the difference