Datalogic Matrix 120 Product Reference Manual page 66

Installation
Matrix 120 is able to decode code labels at a variety of angles. However,
significant angular distortion may degrade reading performance.
When mounting Matrix 120, take into consideration these ideal label position
angles: Pitch or Skew 10° to 20° and Tilt 0°.
Note: Since Matrix 120 is omni-directional on the code plane, the Pitch and Skew
angles have the same significance with respect to the code plane. However, in
some advanced code reading applications performance can be improved by
modifying the Skew angle.
The Pitch, Skew and Tilt angles are represented in
suggestions below for the best orientation.
Position the reader in order to avoid the direct reflection of the light emitted by
the Matrix 120 reader; it is advised to assure at least 10° for the Skew angle.
No Pitch,
Tilt or Skew
In some cases, such as low contrast or low illumination, it can be useful to use a
Pitch or Skew angle = 0°.
The Tilt angle is also represented in
any tilt angle. Keep in mind however, that since linear barcodes are rectangular,
the reader should be aligned to fit them into the horizontal FOV.
52
Tilt
any angle
inside FOV
Pitch
Minimize
Figure 32 - Code Reading Orientation
Figure 33
Figure 32 -. Follow the
Skew
assure at least 10°
-. Matrix 120 can read labels with
Matrix 120