JAI Pulnix TS-2030EN Series, Руководство пользователя

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TS-2030EN/TS-2076EN Series Progressive Scan Cameras
Camera Features
6 Camera Features
6.1 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 TS-2030EN 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 resolution of 512
lines. The TS-2076EN provides a full vertical resolution of 768 lines.
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 TS-2030EN model enables the 30Hz frame rate by scanning 512 lines out of the entire 1080 lines.
This technique significantly reduces smear and blooming, which tend to be significant problems in
daylight outdoor applications such as intelligent transportation systems (ITS).
The TS-2076EN model enables the 21Hz frame rate by scanning 768 lines. The TS-2076EN has higher
smear and blooming incidents than the TS-2030EN. However, for those applications that require more
vertical resolution, users will find that the slightly higher smear and blooming levels of the TS-2076EN
are a good trade-off and make it an excellent choice for red light violation or speed enforcement use.
6.2 Asynchronous Reset
The video signal starts with internal VD. When the external VINIT pulse is applied, internal VD is
latched to HD and the internal VD is delayed to set up the shutter speed period. The shutter speed is
controlled by the dial switch from “0” to “F.” Video output timing starts right after the internal VD and
single shots, FDV is output at the internal VD timing.