36 | CHAPTER 4 – USING AND MAINTAINING YOUR SMART BOARD INTERACTIVE
WHITEBOARD
Pen Tray LEDs and Sensors
When you turn on or reset your interactive whiteboard, the indicator lights
on the pen tray cycle twice. When the system is running, the lights come on only
when you remove a tool. Only one illuminates at a time, indicating the last tool
removed from the pen tray. The pen tray detects the removal of the pens and the
eraser using reflective infrared sensors similar to the ones that detect the presence
of paper in photocopiers.
NOTE
The pen tray tools must reflect infrared light. Old-style black SMART Board
interactive whiteboard pens might not reflect infrared light reliably.
Cleaning the Pen Tray’s Sensors
If the infrared sensors in the bottom of your pen tray’s recesses become obstructed by
dirt, the sensors don’t detect when you remove a pen or the eraser. The recessed
LED doesn’t illuminate, and the lifted tool doesn’t work.
To clean a sensor, moisten a cotton swab with a household glass cleaner, such as
Windex, and then carefully clean the infrared transmitter and receiver.
Infrared Sensors