Waveshare Barcode Scanner Module User Manual page 8

Barcode Scanner Module User Manual
Skew
Skew will reduce the width and space of barcode (scanned), it is the threshold
dimension of high density barcode. It supports up to 65°. However, you'd better
reduce the skew for better and faster scanning.
Pitch
Pitch will decrease the height of barcode. 2° to 3° is the best scanning angle,
which could avoid the direct reflection of barcode. Barcode Scanner Module supports
up to 60° pitch angle. But you should reduce it for better and faster scanning.
8 / 57 Rev1.0 Date:180621