Omron V460-H User Manual page 251

5 Reader Parameters
5-1-2 Focus Position
Definition:
Serial Cmd:
Default:
Options:
Disabled
The focus position is fixed and is not part of the calibration process.
Enabled (Search Method)
Focus position is calibrated to provide the best image quality and performance. This method is a simple
search algorithm that cycles through focus settings and configurates camera settings to try and locate the
desired focus as quickly as possible. This is accomplished when a symbol is decoded. Once a focus
distance that produces a successful decode has been located, the algorithm fine tunes the search to
locate the inside and outside focal distances. The final focus distance is between the inside and
outside values. This method may be time-consuming if the focus is not found on the first pass.
Quick Focus
Quick Focus is quickly locates the focus setting for an object at the center of the field of view. This is
accomplished with minimal image processing, by analyzing a histogram of the image frame. Before
performing focus calibration, a value for exposure and gain is determined. The process then steps
through the focus range of the system capturing the required number of image frames for each focal
position. Then a histogram is performed on each image frame, and the histogram results for each focal
position are averaged. When the process is finished, the data is analyzed and the optimal focus position is
determined.
Note: This method may not work for all applications. This method is not ideal for very small symbols.
5-4
The reader's focus position can be configured by entering the target
distance value, so focus position can usually be configured without calibration.
However, if it is necessary to calibrate the focus distance there are two
methods: the standard Search Method and a Quick Focus method,
both of which are defined below.
<K529,gain,exposure,focus position,symbol type,WOI framing,WOI margin,
line scan height,processing>
Quick Focus
0 = Disabled
1 = Enabled (Decode Required)
2 = Quick Focus
V460-H Industrial Handheld DPM Reader User Manual