Imaging in the 21st century.

Methods which are likely to become increasingly common in the next century for producing images of the eye and related structures are briefly reviewed. Although techniques based on reflected visible light will continue to be of importance, improved versions of methods based on other physical principles will come into increasingly widespread use. Digital image recording will probably play a dominant role and it is concluded that a key feature that will be common to almost all the methods will be their capacity to provide quantitative data on the state of the eye.