VIS-CAM System

1.3.3Illumination

1.3.3 (a) TNF-31 Flash

The TNF-31 Flash generates light in wavelengths that are invisible to the human eye, but visible to the camera. This makes the flash suitable for illuminating both oncoming and receding views of traffic. Unlike near-infrared illuminators, the TNF-31 yields high contrast images of license plates even if they have red characters on white or yellow backgrounds.

The TNF-31 Flash is automatically enabled whenever the TLS-300 Light Sensor determines that ambient light is insufficient to produce a picture of usable quality. When the TNF-31 is enabled, it fires every time the vehicle detector triggers the camera.

1.3.3 (b) White light LED.

JAI offers White LEDs mounted inside the camera enclosure. This option is usually employed when certain rare color combinations on license plates do not yield sufficient contrast with the TNF-31 Flash option alone.

1.3.4VJP-300 Junction Panel.

The VIS J-Panel is the central connection point for the VIS components. The J-Panel is a DIN-Rail mounted PCB equipped with various interface terminals for interconnection of the VIS components; this can be Ethernet connection, serial connection, TTL trigger feed and power supply. It offers the possibility of manually selecting trigger polarity to the camera. Furthermore the J-Panel is equipped with status LED’s and trigger switches for diagnostics and troubleshooting purposes.

1.3.5RS485 Device Server.

The MOXA RS485 Device Server enables connection of RS485 serial devices to the Ethernet. The purpose for the MOXA RS485 Device Server in the VIS system is to convert Ethernet to RS485 communication for the TLS-300 Light Sensor.

1.3.6ENSetup Program.

The ENSetup Program is an Ethernet based software tool specifically designed to assist the installer with VIS installation, and EN-Camera configuration and diagnostics. The program runs on a standard PC / Laptop with Windows XP installed. Refer to Section 4 on page 31 of this manual and the VISCAM 300/400 EN Setup Manual for details.

1.4 Operational Overview.

During installation, the VISCAM and the optional light source are aimed at the area of the road where vehicles and their license plates are most likely to pass through. The Traffic Light Sensor continually registers the ambient light. The camera uses this information to set up exposure variables to ensure an optimal image of the vehicle and license plate. During transition from day to night the camera enables the optional TNF-31 Flash and/or white light LED’s to secure adequate image quality during low ambient light conditions.

1.4.1Trigger Mode

A vehicle passes by a vehicle detector, sending a trigger to the VIS.

The VIS employs a trigger to snap a video image of the vehicle and license plate when they are optimally positioned in the camera field of view.

The optional flash, if used, fires simultaneously with the camera to ensure correct exposure for the image if the ambient lightning is too low.

 

 

 

4

Preparing for Installation

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JAI TS-1327EN, TS-9720EN, TS-2030EN manual Operational Overview