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GL OBAL HE ADQUARTE R OFF ICE S
Corporate & Americas
Renton, W A USA
Tel: +1 425.226 .5700
www.microscan.com
Date: September 6, 2018
Application Note:
Configuring MicroHAWK ID-40/45 for Dynamic Applications
Summary This tech note documents the process of configuring a MicroHAWK ID-40/45 reader to read barcodes at high linear speeds using WebLink 1.3.0.
Background
One of the limiting factors in reading a fast-moving part is the minimum exposure time for the camera. The MicroHAWK ID-40/45 cameras have a minimum exposure time is 50 microseconds. New features in WebLink 1.3.0 provide options to allow the camera to be used for higher linear speed applications. This document applies to the MicroHAWK ID-40/45 cameras with WVGA (0.3MP) & SXGA (1.2MP) sensors. The QSXGA (5MP) ID-40 is not suited for moving applications due to the rolling shutter sensor.
Hardware Setup
We used a MicroHAWK ID-45, SXGA, HD, RED LEDs, High Speed and XMODE (PN: 7432-2000-1005) with the front diffuser removed and mounted perpendicular to the barcode at a standoff of 4 inches (102 mm). The position of the barcode on the rotating platter is equivalent to a movement speed of 330 inches per second (8.38 meters per second).
Figure 1
GL OBAL HE ADQUARTE R OFF ICE S
Corporate & Americas
Renton, W A USA
Tel: +1 425.226 .5700
www.microscan.com
Reader Setup While the part is stationary, the reader can be focused, trained and optimized for the barcode. In this example a Code 128 barcode label is used.
Figure 2
The reader is now optimized for a stationary part, next we can make a few changes to make this a triggered application. In the Setup screen go to the Read Cycle Sequence and set the Read Cycle to Custom as shown in Figure 3 below.
Figure 3
Train
Optimize
Focus
Custom
GL OBAL HE ADQUARTE R OFF ICE S
Corporate & Americas
Renton, W A USA
Tel: +1 425.226 .5700
www.microscan.com
For barcodes moving at fast-linear speeds, the Exposure time will need to be set to a low value (ie. 50us) to eliminate motion blur and the gain will likely need to be set high (ie. 100%) to make the image brighter to read the barcode as shown in figure 4 below.
Figure 4
Due to the fast speed of this example, “330 inches per second”, the code is not readable due to motion blur as can be seen in figure 5 below even when the Exposure was set to its minimum value of 50 µs. The barcode direction of movement is vertical in this example.
Figure 5
Gain Exposure
Motion Blur
GL OBAL HE ADQUARTE R OFF ICE S
Corporate & Americas
Renton, W A USA
Tel: +1 425.226 .5700
www.microscan.com
To correct this issue, a couple of new parameters will be used in WebLink 1.3.0. The power strobe
option must be enabled and for fast moving parts, a fixed light delay time needs to be increased. These
changes are made in WebLink 1.3.0 using the Advanced Setting page. Click the Gear icon > Advanced >
Camera Setup. Change the Illumination Brightness to Extreme as shown in figure 6 below. This will
enable power strobe when the Exposure time is less than 1000 µs.
Figure 6
If the image still has some blur and the exposure is set at 50 µs, go to the Advanced Settings page >
Camera Setup and increase the Fixed Light Delay Time. This effectively shortens the time the reader
light is active, but it will make the image darker because less light is present. Increase this delay time
until the motion blur is eliminated.
The timing diagram (Figure 7) on the next page demonstrates the effect of the Fixed Light Delay Time
setting.
GL OBAL HE ADQUARTE R OFF ICE S
Corporate & Americas
Renton, W A USA
Tel: +1 425.226 .5700
www.microscan.com
Light Delay Timing Diagram
Figure 7
Note:
• Increase the Fixed Light Delay Time in small increments until the best time is found. Increasing
this value reduces the light to the camera and will make the image darker.
• If the Fixed Light Delay Time is using a value greater than 0, a shroud may be required around
the reader to block ambient light.
GL OBAL HE ADQUARTE R OFF ICE S
Corporate & Americas
Renton, W A USA
Tel: +1 425.226 .5700
www.microscan.com
After changing the Illumination Brightness and Fixed Light Delay Time, the image blur is reduced, and
the barcode can be read, Figure 8 below.
Figure 8
GL OBAL HE ADQUARTE R OFF ICE S
Corporate & Americas
Renton, W A USA
Tel: +1 425.226 .5700
www.microscan.com
Additional tips to improve performance
• In high speed applications, mounting the reader perpendicular to the barcode will increase the
light in the image, however it will increase glare on reflective surfaces.
• An ID-45, with the diffuser removed, can be a more effective reading solution vs the ID-40 for
Linear (1D) barcodes because the ID-45 light head provides a larger illumination area.
• Define a window of interest to reduce the image size and search region. Reducing the vertical
height of the image will reduce the image capture time.
• If only reading linear barcodes in a fixed orientation, you can enable Fast Linear Mode to limit
searching in the horizontal or vertical direction. To enable, go to Gear Icon > Advanced >
Symbologies > Fast Linear Mode (at the bottom) and set the desired search direction. This
setting is shown in Figure 9 below.
Figure 9
• In high trigger rate applications, the use of WebLink takes CPU time away from the read to
display the user interface and can cause an occasional No Read. ESP can be used to monitor the
read barcodes without the additional CPU time.