CAMERA LINK FC300ACL Instruction Manual page 11

● Recommended external sync signal
Signal polarit y
・
・ External HD /VD Input pha se Pha se d ifferen ce
(5-2) Level setting
The level setting is mostly divided into the following two groups:
● Gain setting
This is to set the gain (amplification ratio) of the
preamplifier between the CCD imaging device
and the A/D converter.
Communication command H'30
● Offset setting
This is set by the communication command in
serial communication.
Communication command H'32
● Correlation between gain setting value and observed gain value
The setting value of this equipment is controlled by giving 0 to 255. The setting value and the actual GAIN value are
approximately proportional. The approximate value is calculated by the following equation.
CDS GAIN (dB)
Communication command 30H
(Note) When the CCD element receives excessive light with the amplifier set at low gain value due to the restriction of the dynamic
range of the CCD light receiving element, the signals of the nonlinear range of the CCD element and the preamplifier may be
output at the high brightness area. In this state, unnatural image (Note below) may appear in the neighborhood of the
saturating signal area of the image due to the characteristic of the nonlinear area. This phenomenon, which is associated with
the saturation characteristic of the CCD element, is not a failure arising from the camera.
To eliminate this phenomenon, reduce the amount of light by stopping down the lens and newly set a higher gain value. Then,
the output signal from the CCD element at the saturating area will be appropriately saturated into a white level for the output.
(Note)The above described unnatural image represents the following states:
● Black and white look inverted at the saturating area.
● The outline of the saturating area is blurred.
● The saturating area slightly shifts upward and downward.
● The brightness value of the saturating area does not reach 1023.
(Note) The sensitivity correction is sometimes conducted at the factory before shipment using Digital gain function for the purpose of
maintaining sensitivity of the camera. As the output of AD converter are digitally multiplied, the data of some gray levels may be
absent depending output level of AD converter and setting value of digital gain Set the setting value of Digital gain (Control
register: H'31) at "0" to turn the sensitivity correction OFF. The analog gain is employable as per normal.
： Negative log ic
ＨＤ：３．２±１μｓ（Low level）
P ulse w idt h
ＶＤ：１ ～ １３Ｈ （Low level
f ps ±
： ３０
f ps ±
：６ ０
f ps ± 2.6 µ
：９ ０
ＨＤ
ＶＤ
HD Permissible frequen cy de viation
3.64 + 0.132 × ( Setting value + GOFS [ 7..0 ] )
=
Fixed value
）
８ µ ｓ
µ
４ ｓ
ｓ
f ps
３ ０ ： ８ μｓ
f ps
６０ ：４ μ ｓ
f ps .
９ ０ ： ２ ６ μｓ
３０ １５.７３４ＫＨｚ±１％
f ps :
６０ f ps : ３１.４６８ＫＨｚ±１％
９０ f ps : ４７．６７４ＫＨｚ±１％
１０ ２ ３
Signal level
１ ０ ２ ３
０
GAIN OFFSET
Communication command 32H
- 11 -
８ μｓ
４ μｓ
.
２ ６ μｓ
Signal level
Im age signal （
Before setting adjustment
０
ncrease in OFFSET
I
Increase in GAIN
Signal level
１ ０ ２ ３
０
Time
dB
N10316;11/36
）
Time
Time