Omron F150-3 - MANUAL 2 Operation Manual page 75

Adjusting Images
Reference Parameters
The symbol, σ, represents the error standard deviation. It is the standard deviation value of the
difference between the physical coordinates input for calibration settings and the coordinates
after conversion based on the calculated conversion values A to F. It is calculated according to
the following formula:
σ =
(RXi,RYi): Physical coordinates input for calibration settings (i=1 to N).
(X'i,Y'i): Physical coordinates after conversion according to the conversion values (i=1 to N).
N: Data number (sampling places 1 to 3)
Indicates physical width (in X direction) of screen.
"em" indicates the maximum error.
It is the largest value of the differences between the physical coordinates input for
calibration settings and the coordinates after conversion based on the calculated
conversion values A to F. It is calculated according to the following formula:
em = MAX ((RXi−X'i)
MAX: Outputs the largest value of the expression for values (i = 1 to N).
(RXi,RYi): Physical coordinates input for calibration settings (i = 1 to N).
(X'i,Y'i): Physical coordinates obtained after conversion based on the conversion values (i = 1 to N).
N: Data number (sampling places 1 to 3)
Procedure
58
This screen is used to check data settings.
N
[ Σ ((RXi−X'i) 2
+ (RYi−Y'i)
i=1
2
+ (RYi−Y'i)
1
Go to Adjust/Calibration.
Shutter speed
Filtering
BGS levels
Calibration
Light control
2
Select Reference parameters.
The parameters will be displayed.
3
Select OK to exit this screen.
2
)/N]
A to F represent the calibration
conversion values. The camera
coordinates are converted to physi-
cal units based on these calibration
conversion values. The formulae
for conversion to physical units are
as follows:
X' = A × X + B × Y + C
Y' = D × X + E × Y + F
(X,Y): measurement position
(camera coordinates),
unit: pixels
(X',Y'): conversion position
(physical coordinates),
units: mm
2
)
1
Section 3-2