Prolate (Pupil) Apodized Lyot Coronagraphs (PPALC) are known to offer optimal performances for a Lyot-type
Coronagraph configuration, i.e. with an opaque occulting focal mask. One additional benefit of PPALC is its possible
use in a multi-stage configuration. In theory, the coronagraphic performance can be QN, where Q is the energy rejection
factor of one stage (the first one), and N the number of stages. Several ground-based telescopes are considering PPALC
as an option for their high-contrast instrumentation (e.g. Gemini/GPI, EELT/EPICS, Subaru HiCIAO). Although the
PPALC suffers from several limitations, several works are currently focused on fabricating entrance pupil apodizers and
trying to find ways to overcome chromatism issues. In this work, we present the first experimental results from Multi-Stage PPALC (MS-PPALC) that was done in the context of the Japanese space telescope SPICA coronagraph project.
Our entrance pupil apodizers use small diameter High Energy Beam Sensitive glass (HEBS-glass) from Canyon
Materials Inc. The current results show modest coronagraphic performance due to uncompensated phase aberrations
inherent to HEBS-glass material. In addition, and due to these uncompensated phase aberrations, the present optical
configuration is an altered version of the originally planned set-up. However, we can demonstrate the validity the MS-PPALC
concept and compare it to numerical simulations.