User`s manual

AW00098504000 Camera Functional Description
Basler ace Camera Link 23
4 Camera Functional
Description
This chapter provides an overview of the camera’s functionality from a system perspective. The
overview will aid your understanding when you read the more detailed information included in the
later chapters of the user’s manual.
4.1 Overview
Each camera provides features such as a full frame shutter and electronic exposure time control.
Exposure start, exposure time, and charge readout can be controlled by parameters transmitted to
the camera via the Camera Link interface.
Exposure start can also be controlled via an externally generated electrical trigger (ExFrameStTrig)
signal. The ExFrameStTrig signal facilitates periodic or non-periodic acquisition start. Modes are
available that allow the length of exposure time to be directly controlled by the ExFrameStTrig signal
or to be set for a pre-programmed period of time.
Accumulated charges are read out of the sensor when exposure ends. The accumulated charges
are read out of the sensor sequentially, row-by-row. As shown in Figure 6 on page 24, each row
passes through an "analog front end" where the charges are transformed to voltages, gain and
black level are adjusted, and an analog to digital conversion is performed. The A to D conversion
can be performed at 10 bit or at 12 bit depth.
As shown in Figure 7 on page 24, the digitized values from each row are passed to an LVDS block
where they are transmitted to the camera’s FPGA. The Image data is then transmitted via the
Camera Link interface to the frame grabber in your PC. Several different "tap geometries" are
available to determine how the pixel data will be transmitted over the Camera Link interface. The
user can select the desired tap geometry. See Figure 9.3 on page 146 for more detailed information
about tap geometries.
The user can also select from several available pixel clock speeds for the Camera Link interface.
See Section 10.1 on page 157 for more information about selecting the pixel clock speed.