Akiyama, Kunihiko
Watanabe, Ken
Fukui, Masaki
Higuchi, Hiroshi
Noda, Toru
Article History
Received: 1 May 2019
Accepted: 18 October 2019
First Online: 4 November 2019
Competing interests
: Hiroshi Higuchi is an employee of Sony Corporation (Tokyo, Japan). Toru Noda has received lecture fees from Topcon Corporation (Tokyo, Japan) and Leica Microsystems (Heerbrugg, Switzerland).