ALCON HAND HELD AUTO-KERATOMETER

Controls

2. Handle or Ground reference setting.  If set 
to ground it will automatically compensate for 
the axis measurement if you turn the handle 
away from vertical.  For example if you are 
doing keratometry on a bedridden patient.







                                                            3.  The setting can be set to read 
                                                                 either - cylinder or + cylinder.