  To assess the impact of clutter on egocentric distance perception, we
performed a mixed-design study with 60 participants in four different virtual
environments (VEs) with three levels of clutter. Additionally, we compared the
indoor/outdoor VE characteristics and the HMD's FOV. The participants wore a
backpack computer and a wide FOV head-mounted display (HMD) as they
blind-walked towards three distinct targets at distances of 3m, 4.5m, and 6m.
The HMD's field of view (FOV) was programmatically limited to
165{\deg}$\times$110{\deg}, 110{\deg}$\times$110{\deg}, or
45{\deg}$\times$35{\deg}. The results showed that increased clutter in the
environment led to more precise distance judgment and less underestimation,
independent of the FOV. In comparison to outdoor VEs, indoor VEs showed more
accurate distance judgment. Additionally, participants made more accurate
judgements while looking at the VEs through wider FOVs.
