I will be flying at the start of 2018 to Japan and I’m, for various privacy reasons, not comfortable with officials taking a retina scan. Fingerprints ought to be enough!
Therefore: Which airports in Japan do not take retina scans? (I know that all of them take fingerprints of all 10 fingers.)
I’d be especially interested in personal experiences going through the airports in Tokyo and/or Osaka.
As far as I’m aware, and this is from personal experience since I visit Japan several times a year, these are no airports in Japan that do retina scans. You will be fingerprinted (index fingers only, not 10 digits) and photographed, but the camera used for the latter is akin to a consumer webcam (see photo here) and not sufficient to extract retinal information. Retinal scans also require aligning your eyes with the scanner at close range, which is not done at Japanese airports.
Also, the facial recognition gates are currently for Japanese citizens only, compare your face against the biometric image in your passport, and do indeed work with a single shot (although they may allow a second attempt if they can’t match the first time around).