Table of Contents
Advertisement
17-3 CCD trigger
[1] Outline
This function samples a specified part (trigger window) of an image captured by the CCD camera at
a high rate, and starts the measurement when the sampled image changes. Therefore, moving
objects can be measured without requiring an external trigger, such as a photo sensor.
To use this function, set the input/output the CCD trigger on the [I/O CONDITIONS] menu (pages 17-
1 to 17-16), and set item "1TRIG CCD START" and item "2CCD TRIG COND" on the [OBJECT
TYPE I/O] menu. - See item (2).
- There are three methods for starting the measurement when there is a change in a sampled image,
i.e. a "binary method" and an "average light level method and "gray search."
Binary
method
Average light
level method
Gray search
- The trigger window can be set in any position for each object type.
In the past, the position of an external sensor had to be adjusted every time the object type was
changed. However, since this function eliminates the necessity of physical position adjustments, the
changeover time can be reduced.
- The internal CCD trigger can be used with camera 1. (It cannot be used with camera 2.)
- An image that can be used to set the sample window conditions is obtained when the display mode
is switched from the through mode to the freeze mode.
[2] Setting procedure
On the [TYPE MEAS COND] menu, move the cursor to "I/O," and press the SET key.
[TYPE MEAS COND]
1OBJECT TYPE NO.
OPS-MENU SAVE LOCK TITLE FINAL-CALC FINAL-OUTPUT I/O SYSTEM
[OBJECT TYPE I/O]
1TRIG CCD START
1
2CCD TRIG COND
2
3SHUTTER SPEED
4SERIAL OUTPUT
5SET SERIAL BLOCK BLOCK00 MEAS0 CAM1
OPS-MENU RETURN LOCK
1. Move the cursor to item "1TRIG CCD START" with the up and down keys, and press the SET
key.
- Move the cursor to "BIN," "AVG-GRAYS" or "GRAY-SRC" with the left and right keys, and press
the SET key.
When a sampled binary image changes (the white area exceeds 50%), the
measurement is started.
- A change in a binary image means a change in a binary image from black
(background) to white (workpiece) or from white (background) to black
(workpiece).
When the average light level of a sampled image enters a specified
range, the measurement is started.
When the degree of match exceeds the specified value (threshold value), the
measurement will start after the trigger event is detected.
- This is useful when workpieces have complicated shading and cannot be
converted to binary or use a fixed brightness range.
Object type 1
Feeding direction
00(0~63) NO YES
NO YES(BIN AVG-GRAYS GRAY-SRC)
(TO NEXT SUB-MENU)
1/00060(1/30~1/10000)
ANY BLOCK-ASSIGN
17-17
Setting the Input/Output Conditions
Object type 2
Feeding direction
Trigger window
17
Advertisement
Table of Contents
