Basic Operation And Features; Functional Description - Basler L100k User Manual

3 Basic Operation and Features

3.1 Functional Description

BASLER L100
electronic exposure time control and anti-blooming. Exposure time is normally controlled via an
external trigger (ExSync) signal. The ExSync signal facilitates periodic or non-periodic pixel
readout.
When exposure is controlled by an ExSync signal, exposure time can be either edge-controlled,
level-controlled, or programmable. In edge-controlled mode, charge is accumulated over the
entire period of the ExSync signal and a rising edge of ExSync triggers the readout of accumulated
charges from the sensor elements to the CCD shift registers. In level-controlled mode, charge is
accumulated when the ExSync signal is low and a rising edge of ExSync triggers the readout. In
programmable mode, exposure time can be programmed to a predetermined time period. In this
case, exposure begins on the rising edge of ExSync and accumulated charges are read out when
the programmed exposure time ends.
A free-run mode that allows the camera to operate without an ExSync signal is also available. In
free-run mode, the camera generates its own internal control signal and the internal signal is used
to control exposure and charge read out. When operating in free-run, the camera outputs lines
continuously.
At readout, accumulated charges are transported from the light-sensitive sensor elements (pixels)
to the CCD shift registers. The charges from the odd pixels and the charges from the even pixels
are handled by separate shift registers as shown in Figure 3-1. As charges move out of the shift
registers, they are converted to voltages proportional to the size of each charge. Shifting is
clocked according to the camera's internal data rate.
The voltages moving out of each shift register are amplified by a Variable Gain Control (VGC) and
then digitized by a ten bit, Analog to Digital converter (ADC). The digitized video data is
transmitted from the camera to the frame grabber using a format compatible with the Camera Link
standard (see Section 2.3 for details). The camera can transmit video at a ten bit or an eight bit
depth and as a single pixel or a dual pixel stream.
For optimal digitization, gain and offset are programmable via a serial port.
BASLER L100
k Series
DRAFT
line scan cameras employ a CCD-sensor chip which provides features such as
k
Operation and Features
3-1