K12703 ; 9/43
- 9 -
S T RB si gn a l
( 1 1) p in o f C a me r a co n ne c to r
１００Ω
From
internal circuit
74VHCT04A
＋５Ｖ
（
or equivalent
）
6.8ZD
Fig. 4-6. Test pattern
(4-3) Strobe signal output circuit
It is able to adjust the light emitting timing of external strobe light to the exposure time of the camera.
This signal can be output in the continuous shutter mode as well as in the asynchronous shutter mode.
● Strobe signal output circuit
The signal output terminal is used both for strobe signal (STRB)
and busy (BUSY) signal.
Select any of OFF (Default: H level fixed), STRB and BUSY in
configuration setting.
→
Refer to the setting of STRBC0 and STRBC1 in (6-5) Internal flag register
and configuration register
[output voltage range]
(!) The factory default is set to OFF for this camera.
It is required to set STRBC0 flag and STRBC1 flag when outputting STRB or BUSY signal,
● Output signal switching at strobe signal terminal
The signal from this terminal is set to OFF
as a factory default value.
This can be changed to STRB (Strobe timing
signal) or BUSY state by way of rewriting the
configuration register(CR) with serial communication commands.
(CR5) and (CR6) correspond to STRBC0 and STRBC1, respectively
● Strobe signal in continuous shutter mode
This equipment is capable of outputting the strobe signal even in the continuous shutter mode as well as in the
asynchronous shutter mode when the setting is changed to output the strobe timing signal(STRB).
[Explanation] Usage of strobe signal in continuous shutter mode
In the continuous shutter mode, only the incoming light for the time matching the exposure time of the camera is valid.
Accordingly, when a lighting unit is used in the continuous lighting mode, the lighting during the time other than this exposure time
period would be wasted.
Since this equipment is capable of outputting strobe signal (STRB) even in the continuous shutter mode, this output is used as a
trigger signal to control a LED light or other lighting units that can be turned on and off at high frequencies, which helps eliminating
the lighting during the useless lighting time.
The following benefits are derived from this type of lighting control:
● The consumption of the power to a light can be saved by way of lighting only during the valid time for exposure.
● The occurrence of smear is reduced because no light enters any time other than the exposure time periods.
(Note) When the strobe signal is used in the continuous shutter mode to make ON/OFF control on a lighting source unit,
the following must be taken into consideration:
Wherever possible, use a strobe lighting unit or others that are equipped with a power source separated from that
of the camera (electrically isolated power source) and a trigger input terminal (photo coupler input, etc.). If a
lighting unit that shares a power source or a ground circuit with the camera is turned on or off by the strobe signal,
the image output from the camera may have noise due to the influence of the fluctuation of the power supply
voltage or change in the electric potential that occurs at the ON/OFF timing.
Even when the insulation aforementioned is applied, the electromagnetic induction may lead to the occurrence of
noise on the image signal if the electric current of the lighting unit to be control is large. In this case, a measure
must be introduced to reduce electromagnetic induction noise arising from the lighting unit.
(4-4) Test pattern display function
When initially connecting this camera to an image capture board, the use of the test pattern display
function of the equipment makes it easier to confirm that the output timing of the camera and the
details of the signal connection match the particulars of the capture board.
When the test pattern function is set to be ON, the image sensor outputs the test pattern in place of
pictures as shown on the right.
As for this pattern, a numerical value of 1 is simply added in an incremental manner for every
horizontal pixel, and a saw-tooth profile is shown in the range from the numerical value of 0 to 1023.
(Note) In the data, a numerical value of 1 is incrementally added for every horizontal pixel in the
range of 0 to 1023 for the case of 10 bit output, and in the range
of 0 to 255 for the case of 8 bit output.
(Note) The value does not start with 0 at the edge of the effective image area.
H level
5.0V (at 0mA) to 4.0 V (at 10mA)
L level
0.2V (at 0mA) to 0.5 V (at 10mA)
(STRBC1, STRBC0)
Signal name
Remarks
(0,0)
OFF
Always H level (Default)
(0,1)
STRB
Strobe timing
(1,0)
BUSY
Asynchronous shutter busy
0
1023
Test patte rn and hor izontal pr ofile
Shutter exposure time
Continuous lighting
STRB signal
Exposure
Exposure
Valid
Useless lighting time
Valid
Useless lighting time
