Table 1.

Techniques employed for corneal topography in some of the currently used devices.

Technology	Details	Example Topographers
Placido disc	Large-cone topography	CSO Antares, CSO Sirius+ *, CSO MS-39 * Oculus Keratograph 5 M Topcon KR-1W Zeiss Atlas Ziemer Galilei *
Placido disc	Small-cone topography	Medmont E300 Optikon Keratotron
Color light-emitting diode	Point-to-point reconstruction of specular reflections	i-Optics Cassini i-Optics Cassini Ambient

* Devices that enable both corneal topography and tomography images to be obtained.