Chapter 2
Description of measurement functions
2.1 Measurement functions in SpectroPlate „Start“
Dot percentage measurement %
This measurement function displays the
geometric dot area
of a raster screen in
percentage. It is the ratio between the area covered with dots and the total area.
A value of 50 % means for example, that half of the total area is covered with dots.
The right dot percentage value is an important quality control criterion, because is
determines the amount of printing ink transferred to the paper and thus influences
directly the color appearance.
Image mode:
Flashing arrow = Original image:
live image
Pause symbol = Result image:
binary image after
image processing
The device will show a realtime live image, until the green measurement button is pressed.
Then the image calculation delivers within a second the measurement values and the display
turns to the result image.The display turns back to the live image automatically after five
seconds or when the device is moved to another sample.
0°
75°
60 L/cm ( = 0,166 mm )
Dot percentage value
(geometric dot area)
Screen ruling
(= Screen frequency)
Screen angle
Battery status
Zoom factor
The 0°- reference for the screen angle display
is parallel to the front side of the device.
The zoom function
shows the image on
the LCD display with a
zoom factor of up to 4.
Setting of the screen
type.
The AM setting uses AM
calibration data and the
FM setting FM calibrati-
on data accordingly.
For hybrid screens use
AM setting.
Manual TECHKON SpectroPlate Chapter 2 - Measurement functions
Page 19
