Introduction
3
PixeLINK PL-A780
Document No.: 04646-01
MACHINE VISION CAMERA
SYSTEM GUIDE
Copyright © 2004 PixeLINK
All Rights Reserved
2 Introduction
2.1 The PL-A780 Series 6.6 Megapixel Camera
The PL-A780 Series of cameras use a 6.6 megapixel CMOS sensor to achieve high-
resolution images for industrial inspection applications. The PL-A780 comes in monochrome
(PL-A781) and color (PL-A782) versions suitable for industrial machine vision applications.
The sensor used has 2208 (H) by 3000 (V) pixels with a pitch of 3.5 microns. The color
camera uses a Bayer mosaic pattern on the sensor to detect the various colors.
Connected by FireWire, the PL-A780 is fully controlled by software on the host computer.
The PL-A780 camera has a full set of controllable features, such as exposure time, gain,
gamma, saturation and white balance, as well as a number of advanced features not found
on ordinary machine vision cameras. These include:
•
Flexible Region of Interest (ROI) controls and five levels of Pixel Addressing;
•
On-board non-volatile memory for storage of camera settings; and
•
Flat Field Correction (FFC) performed on each pixel on the sensor.
The high resolution allows the camera to resolve small features while maintaining a large field
of view. The selectable ROI and multiple Pixel Addressing modes can be used to control the
resolution of the camera or to maintain high frame rates with larger fields of view. The Pixel
Addressing modes allow the resolution to be reduced by factors of 4, 9, 16, or 36 either by
skipping (decimation), adding (binning), averaging or resampling the pixel data.
The on-board memory allows the camera to be configured on one computer and used on
another without the need for camera configuration files or other configuration data. For
example, the camera could be set up to provide a 648 x 480 field of view at 88 frames per
second with a particular exposure, gamma and white balance settings and these settings
programmed into the camera memory. The next time the camera is initialized, on any PC, it
will default to these settings.
On-board and real-time FFC (illumination correction) is applied to every pixel on the sensor to
provide image quality similar to high-end CCD cameras. For optimal image quality, the FFC
can be calibrated in the field.
The PL-A780 camera has a connector for an external trigger and two General Purpose
Outputs (GPO). The trigger and GPOs can be used to connect the camera to external
hardware for synchronization and control. Multiple cameras can be synchronized together or
lighting can be strobed by using these signals.
The PL-A780 cameras use standard FireWire interfaces for plug-and-play operation. The
FireWire interface provides power, data and control communication from the host computer
to the camera over a single cable. A second FireWire port on the camera can be used to
connect additional cameras in a “daisy chain” on a single FireWire bus.
Fully IEEE 1394 IIDC 1.3 (IIDC) compliant, the PL-A780 can also be used with third party
drivers compatible with the IIDC specification, such as the National Instruments IEEE 1394
for IMAQ driver.
However, to fully enable the camera features on Microsoft Windows systems, it is
recommended to use PixeLINK supplied drivers and the PixeLINK Application Programming
Interface (API) or PixeLINK Developer’s Application to control the PL-A780 camera.
