We recommend positioning the sensor module with the black side upward, and the metal side facing down, towards the mounting area as shown in Sensor Evaluation. By having the black side up, the lasers and diodes will get a little closer to the mounting area, which makes for a better feel.
On a vertical area or display
If you want to position your sensor over a vertical area or display - We recommend positioning the sensor module at the top, facing down with the sensor module's black side positioned upward. This will minimize dust particles and makes the laser go as close to the screen as possible.
If there is no room at the top of the screen, it works just as fine below, or on the sides. Just remember to carefully remove dust periodically to avoid dust effect the touch performance. You can configure and transform the mapping by using either Workbench or our example SDK.