We recommend using the external light shield when testing mesopic vision or glare sensitivity. To obtain the most accurate results with these tests the examinee must be allowed to adapt to the dark for a few minutes. In case your Binoptometer® 4P is set up in a room that cannot be darkened sufficiently, you can use it with the external light shield. This shields the examinee’s eye completely from outside light, allowing the eyes to adapt to the dark.
The external light shield can also help in situations where distracting light reflexes or glare cannot be avoided due to ambient conditions in the examination room.
