JAI TM-6740GE, Operation Manual

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Page 37
Operation
TM-6740GE Hardware
8 Operation
This chapter contains information about performing operational procedures. It contains the following
sections:
• “Progressive Scanning” on page 37
•
“Bayer Color Filter (Color Versions)” on page 40
• “Electronic Shutter” on page 44
• “External Sync” on page 45
• “Asynchronous Reset” on page 45
•
“Programmable Look-Up Table (LUT) and Knee Control” on page 50
• “Camera Timing Charts” on page 51
•
“Video Output” on page 53
• “External HD Locking and External VD Reset” on page 57
•
“Asynchronous Reset” on page 45
8.1 Progressive Scanning
Standard TV-system scanning is 525 lines interlace scanning as specified in the RS-170 protocol. Every
other horizontal line (odd lines and even lines) is scanned at a 60Hz rate per field, and the scanning is
completed with two fields (one frame) at 30Hz rate. Because of the interlace scanning, the vertical
resolution of CCD cameras is limited at 350 TV lines, regardless of the horizontal resolution. When
electronic shutter is applied, the CCD can hold only one field of charge at each exposure. This means
that the vertical resolution of the electronic shutter camera is only 244 TV lines. The situation is the
same for an HDTV-format camera, since it has interlaced scanning and the vertical resolution of the
shuttered image is 500 lines.
The TM-6740GE uses a state-of-the-art progressive scanning interline transfer CCD which scans all
lines sequentially from top to bottom at one frame rate. Like a non-interlace computer screen, it
generates a stable, crisp image without alternating lines and provides full vertical TV resolution of 480
lines. Due to the TM-6740GE’s extremely high frame rate, however, it will not synchronize to most
monitors.
The interline transfer architecture is also important to generate simultaneous shuttering. This is different
from full frame transfer architecture, which requires a mechanical shutter or strobe light in order to
freeze the object motion.
The TM-6740GE outputs the progressive scanned image with an electronic shutter in thirty-six
different formats. See Table 7 on page 39 for more information.
1.
Progressive scanning digital and analog output
The CCD signal goes through A/D converters 10-bit in, 10-bit/8-bit out. The digital
output is available via the Gigabit Ethernet connector.
The analog output is the same as 75 ohms, 714mV format available from BNC and
12-pin connector.