Siemens SIMATIC MV420, Operating Instructions Manual

Page: 37 / 424

Image processing
4.1 Reading code (1D and 2D codes)
SIMATIC MV420 / SIMATIC MV440
Operating Instructions, 04/2013, A5E02371045-06
35
4.1.2.3 Performance characteristics when reading QR codes
Note
Maximum code dimension/unsupported code types
•
Codes with a maximum code dimension of 89 x 89 can be read.
•
The following code types are not supported: Micro QR code, Macro QR code.
Note
Changing the time-saving image acquisition with half resolution
If the cells are larger than 10 pixels, change to time-saving image acquisition at half
resolution. This change is also useful at high object speeds.
The recognition processes of the reader allow reliable and fast reading of printed QR codes
of good quality.
Range of application
● The range of imaging sizes ranges from 5 to 35 pixels per cell. The range is static.
● The codes can have any alignment in the image.
● The code can be printed both dark on a light background and light on a dark background.
● The viewing angle of the reader to the surface can be between 70° and 90°.
● The diameter of the cells must be uniform over the entire code field.
● The contrast between cells and the background must be approximately the same over the
entire code field.
● The image background must have a homogeneous brightness, for example no texture
such as stripes.