When a polarised monitor is used, three additional buttons are added to the Secondary toolbar when in Refraction mode.


These tests may also be selected by pressing 5, 6 or 7 on the keyboard or the IR remote.




Binocular Balancing


The Binocular Balancing test is designed to assist with fine tuning a final spectacle prescription at the end of a refraction.



The top row of letters is seen by the Right eye, the middle by Both eyes and the bottom by the Left eye. The patient is simply asked to confirm that the letters on each row are clear. +/- 0.25 lenses may be offered monocularly to check each eye individually and binocularly to check the overall binocular add.  The natural viewing conditions encourage the patient's accommodation to adopt its natural state providing a reliable endpoint to the refraction.


The letter size may be changed to match the patient's visual acuity using the vertical scroll bar or the up/down cursor keys on the keyboard or remote control.  Different Optotypes may be selected from the pull-down list or by pressing PgUp or PgDn on the keyboard or remote control.


A default set of letters is shown by selecting the O icon or pressing O on the keyboard or remote control.  A random set of letters is shown by selecting the R icon or pressing R on the keyboard or remote control.


A duochrome split can be added by selecting the U icon or pressing U on the keyboard or the remote control.




Monocular LogMAR


The Monocular LogMAR test is designed to provide a stimulus for performing a binocular refraction.  A LogMAR chart is drawn on odd or even rows only meaning that one eye will see the chart while the other sees a blank screen. This avoids occluding one eye during refraction thus allowing more natural viewing conditions.



The Right and Left eye charts are selected by selecting 6 or 7 one the Secondary Toolbar or using the keyboard or remote control.





The controls are the same as for the LogMAR chart where O rotates around the predefined sets and R randomises the letters.  The Vertical cursor control keys and the Vertical scroll bar on the Control Screen change the current LogMAR row and SHIFT+Horizontal cursor control keys rotates around the optotypes.