Functions And Operations; Basic Construction; Main Functions; Partial Scan (Sc) - JAI AT-200CL User Manual

7. Functions and Operations

7.1. Basic construction

A 32-bit micro processor controls all functions in the AT-200CL camera. The CCD sensor
output is normalized in CDS and preamplifiers. The signals are then digitized to 14 bits.
Digital gain control, color matrix, look-up tables and setup can do signal processing in 14 bits
before the signal is converted to a 12-, 10- or 8-bit Camera Link signal.
CCD
Light

7.2. Main functions

7.2.1 Partial scan (SC)

The partial scanning function uses the middle of the image vertically to achieve faster frame
rates. This is very useful when capturing and inspecting an image which does not require the
full height. The AT-200CL has 4 types of pre-set partial scan modes: 2/3, 1/2, 1/4 and 1/8.
Fig.13 Partial scan (pre-set)
In addition to pre-set partial scan modes, the AT-200CL has a variable partial scan mode. The
start line can be set from the 1st line to 1236th line and the end line can also be set from the
1st line to the 1236th line. In actual use, the start line should always be set smaller than the
end line and the end line should be larger than the start line. For instance, if the end line is
set at 1236, the start line should be 1235 or smaller. If the start line is set at 1, the end line
should be set at 2 or larger.
AT-200CL
CCD
CCD
Fig. 12. Principle diagram for signal processing
Fast Dump
Normal Scan
Fast Dump
4
0
50
450 550 600 650 700 750 nm
0
0
4
0
50
450 550 600 650 700 750 nm
0
0
4
0
50
450 550 600 650 700 750 nm
0
0
Mode Start line
2/3 206
1/2 308
1/4 463
1/8 541
- 15 -
R ch
A/D & process circuit
Blemish compensation
Shading compensation
Color matrix
LUT/Gamma/Knee
G ch
A/D & process circuit
Blemish compensation
Shading compensation
Color matrix
LUT/Gamma/Knee
B ch
A/D & process circuit
Blemish compensation
Shading compensation
Color matrix
LUT/Gamma/Knee
End line Frame Rate
1030 28.42 fps
35.27 fps
928
773 55.89 fps
695 79.23 fps