Table 1: Main properties of the PIAA configuration and 3 CPA configurations. IWD stands for Inner Working Distance, and is the smallest angular distance at which a 10⁹ contrast is reached in the PSF. The Discovery space is the fraction of the field of view usable for faint companion detection.
Transmission IWD Discovery Space

PIAA 1.00 $\approx$ $1.5 \lambda/d$ 1.00

Jacquinot 0.285 $\approx$ $5 \lambda/d$ $\approx$ 0.25

Spergel 0.273 $\approx$ $4 \lambda/d$ $\approx$ 0.5

ASA 0.107 $\approx$ $4 \lambda/d$ $\approx$ 0.5

(increases

with distance)

**Table 1:** Main properties of the PIAA configuration and 3 CPA configurations. IWD stands for Inner Working Distance, and is the smallest angular distance at which a 10⁹ contrast is reached in the PSF. The Discovery space is the fraction of the field of view usable for faint companion detection.
	Transmission	IWD	Discovery Space
PIAA	1.00	$\approx$ $1.5 \lambda/d$	1.00
Jacquinot	0.285	$\approx$ $5 \lambda/d$	$\approx$ 0.25
Spergel	0.273	$\approx$ $4 \lambda/d$	$\approx$ 0.5
ASA	0.107	$\approx$ $4 \lambda/d$	$\approx$ 0.5
			(increases
			with distance)

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