Schäfter+Kirchhoff SK6288U3KOC User manual

SK6288U3KOC
3
2
Sample Configuration
1CCD line scan camera
SK6288U3KOC
mounted with
2Mounting bracket SK5105
3Clamping claws SK5102
4Photo lens SK1.4/50-40
(integrated focus/aperture adjustment)
4
1
Schäfter + Kirchhoff © 2016 • Line Scan Camera SK6288U3KOC Manual (02.2016) • shared_Titel_ML.indd (02.2016)
Kieler Str. 212, 22525 Hamburg, Germany • Tel: [phone] • Fax: [phone] • [email protected] •www.SuKHamburg.de
SK6288U3KOC
Color Line Scan Camera
3x 2096 pixels, 14 µm x 14 µm, 60 / 30 MHz pixel frequency
Instruction Manual
02.2016
Read the manual carefully before the initial start-up. For the contents table, refer to page 3.
The right to change the described specifications is retained as the products undergo continuous cycles of improvement.
USB 3.0
• Robust cable connections
• Hot-pluggable
• Perfect for movable setups

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SK6288U3KOC Instruction Manual (02.2016) © 2016
Schäfter + Kirchhoff GmbH • Hamburg
How to Use this Instruction Manual
Electricity Warning
Assembly and initial operation of the line scan camera must be carried out
under dry conditions.
Do not operate the camera if you notice any condensation or moisture in
order to avoid danger of a short circuit or static discharge!
Risk of High Power Lighting
According to the application, laser or high power LED light sources might be
used. These can affect your eyesight temporarily or even cause permanent da-
mage to the eyes or skin.
Do not look directly into the light beam!
Mechanical Warning
Ensure that the scanner axis is free to move and that no obstacles are in the way
– especially fingers!
Do not place any body parts in the way of moving parts!
For typical use in a scanning application, please consider the following
warnings:
Safety Warnings
Please read the following sections of this Instruction Manual before unpacking,
assembly or use of the Line Camera System:
• The safety warnings on this page
• Introduction to the system, page 4
• Assembly and initial setup, page 6
Keep this Instruction Manual in a safe place for future reference.
!

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SK6288U3KOC Instruction Manual (02.2016)
© 2016
Schäfter + Kirchhoff GmbH • Hamburg
How to Use this Instruction Manual................................................................................. 2
Safety Warnings .............................................................................................................. 2
Contents ......................................................................................................................... 3
1 Introduction ................................................................................................................ 4
1.1 Intended Purpose and Overview................................................................................................ 4
1.2 System Setup at a Glance ......................................................................................................... 4
1.3 Computer System Requirements............................................................................................... 5
1.4 SK6288U3KOC Line Scan Camera - Specifications.................................................................. 5
2 Installation and Setup ................................................................................................. 6
2.1 Mechanical Installation: Mounting Options and Dimensions..................................................... 6
2.2 Electrical Installation: Connections and I/O Signals .................................................................. 7
2.3 USB3 Connections and SkLineScan Software Installation........................................................ 8
SkLineScan Installation and Automatic Camera Driver Installation
SkLineScan Start-up
Camera Setup
Initial Function Test
3 Camera Control and Performing a Scan..................................................................... 10
3.1 Software: SkLineScan.............................................................................................................. 10
Function Overview: SkLineScan Toolbar
Basic Visualization of the Sensor Output
3.2 Adjustments for Optimum Scan Results.................................................................................. 12
Lens Focussing
Sensor Alignment
Gain/Offset Control Dialog
White Balance and Shading Correction
Integration Time
Synchronization of the Imaging Procedure and the Object Scan Velocity
Synchronization Modes
RGB Sensors: 2D Imaging and Pixel Allocation
4 Advanced SkLineScan Software Functions ................................................................ 22
4.1 Camera Control by Commands ............................................................................................... 22
Set Commands
Request Commands
4.2 Advanced Synchronization Control.......................................................................................... 24
Advanced Trigger Functions and Sync Control Register Settings
Example Timing Diagrams of Advanced Synchronization Control
5 Sensor Information.................................................................................................... 26
Glossary ........................................................................................................................ 30
CE-Conformity............................................................................................................... 31
Warranty........................................................................................................................ 31
Accessories and Spare Parts......................................................................................... 32
Contents

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1 Introduction
SK6288U3KOC Instruction Manual (02.2016) © 2016 Schäfter + Kirchhoff GmbH • Hamburg
The SK line scan camera series is designed for a wide
range of vision and inspection applications in industrial
and scientific environments. The SK6288U3KOC is highly
portableandtherobustlyattached dedicated connections
enable external synchronization of the camera and the
output of data to the USB 3.0 port of the computer.
The USB 3.0 connection supplies power to the camera
and the camera is hot-pluggable, providing the greatest
degree of flexibility and mobility. The computer does not
require a grabber board, allowing a laptop to be used
when space or weight restrictions are also at a premium.
Once the camera driver and the SkLineScan®program
have been loaded from the SK91USB3-WIN CD then the
camera can be parameterized. The parameters, such as
integration time, synchronization mode or shading
correction, are permanently stored in the camera even
after a power-down or disconnection from the PC.
The oscilloscope display in the SkLineScan®program
can be used to adjust the focus and aperture settings, for
evaluating field-flattening of the lens and for orientation
of the illumination and the sensor, see 3.1 Software:
SkLineScan, p. 10.
1 Introduction
1.1 Intended Purpose and Overview
red: SK6288U3KOC scope of delivery
blue: accessories for minimum system configuration
black: optional accessories
For accessory order details see Accessories and Spare
Parts, p. 32.
1.2 System Setup at a Glance
Motion unit
with
encoder
Synchronization cable
USB cable
Computer
Schäfter+Kirchhoff
USB 3.0 camera driver
Schäfter+Kirchhoff
Software Development Kit
Schäfter+Kirchhoff
VI library for LabVIEW®
Line scan camera
Clamping claw
Mounting bracket
Optics (e. g. lens,
focus adapter,
tube extension ring)

Note:
This camera is not USB 2.0 compatible. For operation with an USB 2.0 interface request for a factory-preset pixel
frequency limitation. This will reduce the data transfer rate as well as the power consumption to the USB 2.0
specifications.
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1 Introduction
SK6288U3KOC Instruction Manual (02.2016)
© 2016
Schäfter + Kirchhoff GmbH • Hamburg
1.3 Computer System Requirements
1.4 SK6288U3KOC Line Scan Camera - Specifications
1 Introduction
• Intel Pentium Dual Core or AMD equivalent
• RAM min. 4 GB, depending on the size of acquired
images
• USB 3.0 interface. With a USB 2.0 interface, there
are limitations, see footer.
• High-performance video card, PCIe bus
• Operating Systems:
Windows 7 / 8.1 / 10 (64 or 32-bit) or
Linux kernel 3.13 or higher, Debian or openSUSE
• CD/DVD drive for software installation
Sensor category CCD Color Sensor
Sensor type KLI2113
Pixel number 3x 2096
Pixel size (width x height) 14 x 14 µm2
Pixel spacing 14 µm
Line spacing, line sequence 112 µm, blue (B) - green (G) - red (R)
Active sensor length 29.3 mm
Anti-blooming -
Integration control x
Shading correction x
Line synchronization modes Line Sync, Line Start, Exposure Start, Exposure Active
Frame synchronization x
Pixel frequency 60 / 30 MHz
Maximum line frequency 9.28 kHz
Integration time 0.01 ... 20 ms
Dynamic range 1:2500 (rms)
Spectral range 400 ... 700 nm
Video signal color 8/12 Bit digital
Interface USB 3.0
Voltage USB (600 mA)
Power consumption 3.0 W
Casing Ø65 mm x 54 mm (Case type AT2)
Objective mount M40x0.75
Flange focal length 19.5 mm
Weight 0.2 kg
Operating temperature +5 ... +45°C

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2 Installation and Setup
SK6288U3KOC Instruction Manual (02.2016) © 2016 Schäfter + Kirchhoff GmbH • Hamburg
2 Installation and Setup
2.1 Mechanical Installation: Mounting Options and Dimensions
Casing type AT2
Mounting Options
• The best fixing point of the camera is the collar for
the mounting bracket SK5105 (available as an
accessory).
• Four threaded holes M3x 6.5 mm provide further
options for customized brackets.
• The length and weight of the optics might be beyond
the capability of the standard mounting bracket
SK5105. For this purpose, a second mounting
bracket type SK5105-2 to hold the tube extension
ring(s) is more appropriate.
Optics Handling
• If the camera and the optics are ordered as a kit,
the components are pre-assembled and shipped
as one unit. Keep the protective cap on the lens
until the mechanical installation is finished.
• If you must expose the sensor or lens surface,
ensure the environment is as dust-free as possible.
• Gently blow off loose particles using clean
compressed air.
• The sensor and lens surfaces can be cleaned with
a soft tissue moistened with water or a water-based
glass cleaner.
Mounting bracket SK5105
Mounting system SK5105-2
for cameras with a tube
extension > 52 mm
Clamping set SK5102
Set of 4 pcs. clamping claws
incl. screws
66
50
20
16.5
3.5 6.5
10 10
36
M3 Ø3.3
Ø4.3
6
15
50.3
41.7
70
63
40
Ø 42
M4
1/4’’ 20G
6
36
Ø 42
70
3.5 31.5
25
10
3.5
70
63
40
1/4’’20G
M4
Ø4.3
Hex socket head screw
DIN 912–M3x12
Clamping claw
Pixel 1
M3 (4x)
depth 6.5 mm
61.5Ø65
M40x0.75 2.5 6
FFL
41.7
Ø42
12.7
Lens mount: M40x0.75
Seat for bracket: Ø42 mm
Flange focal length: FFL = 19.5 mm
CCD-Sensor
AT2

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2 Installation and Setup
SK6288U3KOC Instruction Manual (02.2016)
© 2016
Schäfter + Kirchhoff GmbH • Hamburg
2.2 Electrical Installation: Connections and I/O Signals
All Schäfter + Kirchhoff USB 3.0 line scan cameras can be operated with a USB 2.0 interface. Note that there might
be limitations in terms of the maximum data transfer rate and the power supply. The details for your camera can be
found in section 1.4 Line Scan Camera - Specifications, p. 5.
2 Installation and Setup
Accessories (see also Accessories and Spare Parts, p. 32):
• TheUSB 3.0 interfaceprovides datatransfer,camera controland powersupply capabilitiesto theSK6288U3KOC
line scan camera. If you want to operate the camera in Free Run (SK Mode 0) trigger mode the USB3.0 cable
is the only connection you have to make.
• For any kind of synchronized operation, the external trigger signal(s) must be wired to socket 2. A frame-
synchronization signal and two separate line-synchronization signals can be handled. The various trigger
modes are described fully in section Synchronization of the Imaging Procedure and the Object Scan Velocity,
p. 18
2
1
3
4
5
6
7
8
9
10
1112
2
1
3
4
5
6
Synchronization
Socket: Hirose series 10A, male 6-pin
2
Pin Signal Pin Signal
1Line Sync B 4NC
2NC 5Line Sync A
3Frame Sync 6GND
Line Sync A/B and Frame Sync: TTL levels
3Status indicator
off no power, check the USB link for a fault.
red power on
green power on, firmware is loaded, camera is ready
External synchronization cable SK9026.x
Use this cable to feed external synchronization signals
into socket 2.
Connectors:
Hirose plug HR10A, female 6pin (camera side)
Phoenix 6 pin connector incl. terminal block
Cable length:
3.0 m SK9026.3
5.0 m SK9026.5
USB 3.0 cable SK9020.x
For connecting socket 1with the PC or USB hub.
Cable length:
3.0 m SK9020.3 (standard)
5.0 m SK9020.5
1Data and power
USB 3.0 socket type µB with threaded holes for locking screws
Power: 3.0 W

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2 Installation and Setup
SK6288U3KOC Instruction Manual (02.2016) © 2016
Schäfter + Kirchhoff GmbH • Hamburg
2.3 USB3 Connections and SkLineScan Software Installation
2 Installation and Setup
This section is a quick reference for installing the SkLineScan adjustment and configuration software and to set
up the USB3 camera driver. SkLineScan and the SkLineScan manual is provided for download on the
Schäfter + Kirchhoff website under http://www.sukhamburg.com/support.html. It is also part of the fee-based
software development kit SK91USB3-WIN.
SkLineScan Installation and Automatic Camera Driver Installation
Prior to the installation, power on the PC (not the camera) and unpack the downloaded zip-file to a temporary
folder. Alternatively, if your installation medium is a CD, insert the disk to the drive.
The autostart function may launch the setup program automatically from CD. Otherwise, look for one of these
installation files:
SkLineScan-USB3-Win_x64.msi SK91USB3-Win_x64.msi
SkLineScan-USB3-Win_x86.msi SK91USB3-Win_x86.msi
Then start the applicable installation file manually. This will set up the Schäfter + Kirchhoff SkLineScan camera
control and adjustment tool as well as the USB3 Line Scan Camera Driver.
Step 1: Install SkLineScan. The setup program will
automatically install the Schaefter +
Kirchhoff USB3 Line Scan Camera Driver.
Step 2: Plug in the USB3 connection cable to the
camera. if appropriate switch on the external
power supply.
Step 3: Start the SkLineScan program.
Initial Function Test
• Quit the SkLineScan startup dialog
box.
• Select "OK" in the SkLineScan
start-up dialog.
The Signal Window showing the current
brightness versus the pixel number
indicates the correct installation.
Camera Setup
Use the Setup dialog for
• activating/deactivating a connected USB3 camera
(activated device is ticked)
• changing the pixel frequency
• setting the bit depth of the video signal to 8 or 12-bit.
In USB 2.0 mode the lower pixel frequency and 8-bit video
signal is recommended SkLineScan Setup dialog
SkLineScan Start-up
• Start SkLineScan.
• A start-up dialog box pops up and
displays the connected camera(s) that
have been automatically detected. It
also indicates the active USB standard. The optimum
performance is provided by USB3.0.
• The camera LED changes from red to green color light.
Desktop Icon

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SK6288U3KOC Instruction Manual (02.2016)
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3 Camera Control and Performing a Scan
SK6288U3KOC Instruction Manual (02.2016) © 2016 Schäfter + Kirchhoff GmbH • Hamburg
3 Camera Control and Performing a Scan
Function Overview: SkLineScan Toolbar
New line scan. All open "Signal window" windows will be closed. [F2]
"Camera Control" dialog for parameter settings: integration time, line frequency, synchronization mode,
thresholding
Zooming in and out
New line scan. "Area Scan" windows will be closed, "Signal window" windows will remain open. [F2]
Threshold mode in new binary signal window.
"Shading Correction" dialog to adjust the white balance [Alt + s]
"Gain/Offset Control" dialog, also for commands input [Shif+F4]
New area scan
For an in-depth guide on how to perform imaging and to use the obtained data using the Schäfter + Kirchhoff
software package, see the SkLineScan Software Manual.
The most common functions of the line scan camera can be controlled by menu items and dialog boxes.
Commands controlling comprehensive camera functionality can be entered in the "Camera Gain / Offset
Control" dialog.
Click on the desktop icon to start the SkLineScan
program.
The SkLineScan program recognizes the connected line
scan cameras automatically. The identified cameras are
shown in the start-up dialog A, and the index order
corresponds with the individual MAC addresses of the
cameras.
If the SK6288U3KOC camera is identified correctly,
confirm with "OK". The "Signal window" graphicaly
showing the intensity signals of the sensor pixels (oscil-
loscope display) will open. It is responsive in real-time
and the zoom function can be used to highlight an area
of interest. The oscilloscope display is ideally suited for
parameterizing the camera, for evaluating object
illumination, for focussing the image or for aligning the
line scan camera correctly.
3.1 Software: SkLineScan
This section is a brief introduction to the SkLineScan adjustment and configuration software. A more detailed
description is provided in the separate SkLineScan manual. The pdf is included in the SkLineScan installation
package or is available for download from the Schäfter + Kirchhoff website under http://www.sukhamburg.com/
support.html.
SkLineScan: Toolbar
SkLineScan: Start-up dialog
A

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Schäfter + Kirchhoff GmbH • Hamburg
Basic Visualization of the Sensor Output
Signal Window / Oscilloscope Display
The signal window plots the digitalized brightness profile as signal intensity (y-axis) versus the sensor length (x-axis)
at a high refresh rate. The scaling of the y-axis depends on the resolution of the A/D converter: The scale range is
from 0 to 255 for 8-bits and from 0 to 4095 for 12-bits. The scaling of the x-axis corresponds with the number of
pixels in the line sensor.
Zoom Function
For high numbers of sensor pixels, the limited number of display pixels might be out of range, in which case the
zoom function can be used to visualize the brightness profile in detail. Magnification of one or several sections of
the signal allows individual pixels to be resolved for a detailed evaluation of the line scan signal.
Window Split Function
The signal window can be split horizontally into two sections. Use the split handle Bat the top of the vertical scroll
bar and afterwards arrange the frames using the zoom buttons in the toolbar.
Line scan in Signal
Window: brightness
vs. pixel number
B
Line scan in Signal
Split signal window.
The upper frame
shows a magnified
section of the lower
frame.

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SK6288U3KOC Instruction Manual (02.2016) © 2016
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3.2 Adjustments for Optimum Scan Results
• Lens focussing
• Sensor alignment
• Gain/Offset
• Shading correction
• Integration time
• Synchronization of the sensor exposure and
the object surface velocity, trigger mode
options
Prior to a scan, the following adjustments and parameter settings should be considered for optimum scan
signals:
Start with the signal window / oscilloscope display. Any changes in the optical system or camera parameters
are displayed in real-time when using an open dialog box.
Lens Focussing
The oscilloscope display facilitates the effective focussing of the line scan camera system, even for two-dimensional
measurement tasks. For determining the correct focus, the edge steepness at dark-bright transitions and the
modulation of the line scan signal are the most important factors.
• Adjust the focus using a fully opened aperture to restrict the depth of field and to amplify the effects of focus
adjustments.
• The signal amplitude may require trimming when using a fully opened aperture and this can achieved most readily
by shortening the integration time, as described in section Integration Time, p. 17.
3 Camera Control and Performing a Scan
Out-of-focus:
• Low edge steepness
• Signal peaks are blurred
• High-frequency gray values with low
modulation
Optimum focus:
• Dark-bright transitions with steep edges
• Large modulation in the signal peaks
• High-frequency gray value variations

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SK6288U3KOC Instruction Manual (02.2016)
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Schäfter + Kirchhoff GmbH • Hamburg
Sensor Alignment
If you are operating with a linear illumination source, check the alignment of the illumination source and the sensor
prior to performing a shading correction, as rotating the line sensor results in asymmetric vignetting.
Sensor and optics rotated in apposition Sensor and optics aligned
Gain/Offset Control Dialog
Cameras are shipped prealigned with gain/offset factory settings. Open the "Gain/Offset Control" dialog [Shift+F4]
to re-adjust or customize these settings.
Gain/Offset Control dialog
The gain/offset dialog contains up to 6 sliders for altering gain and offset. The number of active sliders depends on
the individual number of adjustable gain/offset channels of the camera. When "Coupled Gain Channels" is ticked,
all channels are adjusted synchronously with one slider.
The 'Camera Control' frame on the right is available for using commands and advanced software functions. (4.1
Camera Control by Commands, p. 20)
2. Adjust channel 1 gain
and minimize difference
between channels
using Gain slider
1. Adjust channel 1 zero
level and minimize diffe-
rence between channels
using Offset slider
Offset and gain adjustment for more than one gain/offset channel
Adjustment principle
1. Offset
To adjust the zero baseline of the video signal, totally
block the incident light and enter "00" (volts) for channel 1.
For a two- or multi-channel sensor, minimize any diffe-
rences between the channels by adjusting the other
Offset sliders.
A slight signal noise should be visible in the zero baseline.
2. Gain
Illuminate the sensor with a slight overexposure in order
to identify the maximum clipping. Use the Gain slider "1"
to adjust the maximum output voltage.
For a two- or multi-channel sensor, minimize any diffe-
rences between the channels by adjusting the other Gain
sliders.
For the full 8-bit resolution of the camera, the maximum
output voltage is set to 255 and for 12-bit is set to 4095.

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SK6288U3KOC Instruction Manual (02.2016) © 2016
Schäfter + Kirchhoff GmbH • Hamburg
Shading Correction compensates for non-uniform illumination and lens vignetting, as well as any differences in pixel
sensitivity. The signal from a white homogeneous background is obtained and used as a reference to correct each
pixel of the sensor with an individual factor. The result is a leveled signal along the full sensor length. A shading
correction with a balanced RGB sensitivity ensures a natural color reading. The reference signal is stored in the
Shading Correction Memory (SCM) of the camera and subsequent scans are normalized using the scale factors from
this white reference.
Step 1: White Balancing
• Use a homogeneous white object, e.g. a white sheet of paper, to acquire the RGB line signals.
Color line signal with separated RGB curves
White Balancing by Gain Adjustment
• Open the "Gain/Offset Control" dialog. Use the gain sliders to adjust all three curves to the same level. Some
camera models provide two gain/offset channels - thus two sliders - per color.
"Gain/Offset Control" Dialog
3 Camera Control and Performing a Scan
White Balance and Shading Correction

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White Balancing by Individual Integration Time Control
In some circumstances, it is not possible to adjust the white balance using the gain setting because of:
• dynamic limitations from a very intensive or weak illumination,
• undesired changes in noise level.
For such situations, an individual adjustment of integration times for the Red, Green, and Blue channels is
available, for a general description of the integration time adjustment, see section Integration Time, p. 17.
1. Check that the weakest color signal is higher than about 70%. If necessary, adjust the line frequency or the
illumination intensity accordingly.
2. Tick the box "Decoupling LF" Ain the
"Camera Control" dialog.
3. Reduce the integration times for the two
color channels with the higher signals in
order to align the Red, Green and Blue
channels to the same level.
The Red channel is adjusted using the slider
"Exposure Time". B
For the Green and Blue channels, enter the
exposure time into the respective boxes. C
Color line signal with the Red signal adjusted to that of the Blue channel; the Green channel is still separate
Color line signal with balanced RGB curves
A
B
C

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A Using a white homogeneous
background
• Open the Shading Correction dialog
(Alt+s).
Use the entries in the left column to obtain
shading correction reference data from a
white homogeneous background.
• Use a homogeneous white object to
acquire the reference data, e.g. a white
sheet of paper.
• Either take a 2-dimensional scan ("Area
Scan Function" [F3] ) or
use a single line signal that was averaged
over a number of single line scans.
• To suppress any influence from the surface
structure, move the imaged object during
the image acquisition.
• Input the scale range:
Minimum in %: intensity values lower than
“Minimum” will not be changed.
A typical appropriate value is 10% of the full
intensity range, i.e. 26 (= 10% · 255) for an 8-bit
intensity scale.
Maximum in %: target value for scaling
A typical appropriate value is 90% of the full
intensity range. The result will be a homogeneous
line at 230 (= 90% 255) for an 8-bit intensity scale.
• Click on button New Reference
• Click on Save SCM to Flash to save the SCM
reference signal in the flash memory of the camera
B Analytic compensation of
natural lens vignetting
• Open the Shading Correction dialog (Alt+s).
Use the entries in the middle column to calculate
the reference data based on the imaging setup.
• Enter the parameters focal length (FL), sensor
length (SL) and field of view (FOV) according to your
setup.
The implemented algorithm will compensate the
natural lens vignetting.
• Click on Save SCM to Flash to save the SCM
reference signal in the flash memory of the camera
Step 2: Obtaining the Shading Correction Data
The shading correction refrence data that is stored in the shading correction memory (SCM) can be obtained in
two ways:
Shading Correction dialog
Parameters for correction of natural lens vignetting:
FL = Focal Length of the lens in mm
SL = Sensor Length in mm
FOV = Field Of View in mm
Power-down and Power-up Behaviour
The shading correction memory (SCM) buffer is a volatile
memory. Its content is lost on power-off.
Once the reference signal is copied from the SCM to the
camera flash memory, it will persist even after a power-
down. On a re-start, this data will be restored automatically
from the flash memory back into the SCM.
The shading correction status on shutting down - active or
not active - will be retained and automatically restored on
power-up.
Color line signal with
separated RGB
curves after Gain
Adjustment and
Shading Correction
Save SCM to Flash Save the SCM reference signal in
the flash memory of the camera
ON Activate Shading Correction with
the reference signal that is stored
in the SCM.
OFF Switch off Shading Correction. This
does not affect the content of the
camera SCM buffer or the camera
flash memory.
Save SCM to File The SCM reference signal will be
stored in a file.
Load File to SCM A stored reference signal will be
loaded into the SCM of the
camera. If the load process
completes then the Shading
Correction is active.

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Integration Time
The range of intensity distribution of the line scan signal
is affected by the illumination intensity, the aperture
setting and the camera integration time. Conversely, the
aperture setting influences the depth of field as well as
the overall quality of the image and the perceived illumi-
nation intensity.
The line scan signal is optimum when the signal from the
brightest region of the object corresponds to 95% of the
maximum gain. Full use of the digitalization depth (256 at
8-bit, 4096 at 12-bit) provides an optimum signal sensi-
tivity and avoids over-exposure (and blooming).
A camera signal exhibiting insufficient gain: the
integration time is too short as only about 50%
of the B/W gray scale is used.
Optimized gain of the camera signal after incre-
asing the integration time, by a factor of 4, to
95% of the available scale.
Shading Correction Memories and API Functions
As an alternative to the user dialog, a new shading correction reference signal can also be created by using appli-
cation programming interface (API) functions. The relationshhip between the storage locations and the related API
functions are shown in the diagram below. The API functions are included in the SK91USB3-WIN software package.
See the SK91USB3-WIN manual for details.
Structure of the shading correction memories and the related API functions for memory handling
3 Camera Control and Performing a Scan
• Open the "Camera Control" dialog.
Menu Edit -> Operation Parameters or [F4]
• The integration time can be set by two vertical sliders
or two input fields in the section "Integration Time"
of this dialog. The left slider is for coarser the right for
finer adjustments.
• The current line frequency is displayed in the Line
Frequency status field.
• The adjustment of the integration time in the range of
Integration Control (shutter) that is shorter than the
minimum exposure period does not change the line
frequency. This will be held at the maximum.
• The 'Default' button sets the integration time to the
minimum exposure period that is determined from
the maximum line frequency.
• 'Reset' restores the start values.
• 'Cancel' closes the dialog without changes.
• 'OK' stores the integration time values and closes the
dialog.
• For synchronization settings, see section Synchro-
nization of the Imaging Procedure and the Object
Scan Velocity, p. 18.
SkLineScan Camera Control dialog

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The optimum object scan velocity is calculated from:
WP·fL
VO=
ß
If the velocity of the object carrier is not adjustable
then the line frequency of the camera must be adjusted
to provide an image with the correct aspect ratio,
where:
VO·ß
fL=
WP
VO= object scan velocity
WP= pixel width
fL= line frequency
S= sensor length
FOV = field of view
ß= magnification
= S / FOV
Synchronization of the Imaging Procedure and the Object Scan Velocity
• A two-dimensional image is generated by moving either the object or the camera. The direction of the translation
movement must be orthogonal to the sensor axis of the CCD line scan camera.
• To obtain a proportional image with the correct aspect ratio, a line-synchronous transport with the laterally
correct pixel assignment is required. The line frequency and the constant object velocity have to be
coordinated.
• In cases of a variable object velocity or particularly high accuracy requirements then an external synchroni-
zation is necessary. The various synchronization modes are described below.
Example 1:
Calculating the object scan velocity for a given field of view and line frequency:
Pixel width = 14 µm
Line frequency = 9.28 kHz
S= 29.3 mm
FOV = 50 mm
14 µm · 9.28 kHz
VO=
(29.3 mm / 50 mm)
= 222 mm/s
Example 2:
Calculating the line frequency for a given field of view and object scan velocity:
Pixel width = 14 µm
Object scan velocity = 200 mm/s
S= 29.3 mm
FOV = 50 mm
200 mm/s · (29.3 mm / 50 mm)
fL=
14 µm
= 8.4 kHz
3 Camera Control and Performing a Scan
FOV
S
V0
Pixel #1
Pixel #1
WP/ ß
CCD Sensor
Scan Object

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3 Camera Control and Performing a Scan
SK6288U3KOC Instruction Manual (02.2016)
© 2016
Schäfter + Kirchhoff GmbH • Hamburg
3 Camera Control and Performing a Scan
Schäfter + Kirchhoff differentiates several trigger
modes identified by a number, which can be
selected in the control dialog as appropriate.
• Open the 'Camera Control' dialog [F4] to
configure the synchronization. The trigger mode
settings are available in the middle frame.
• Frame- and line-triggered synchronization can
be combined. Tick the 'Frame Sync' box to
activate the frame synchronization mode.
• The Trigger Control stage is followed by a
Trigger Divider stage inside the camera. Enter
the division ratio into the 'Divider' field.
Free Run / SK Mode 0
The acquisition of each line is internally synchronized (free-running) and the next scan is started automatically on
completion of the previous line scan. The line frequency is determined by the programmed value.
LineStart / SK Mode 1
On an external trigger, the currently exposed line will be read out at the next internal line clock. The start and duration
of exposure are controlled internally by the camera and are not affected by the trigger. The exposure time is program-
mable and the trigger does not affect the integration time. The line frequency is determined by the trigger clock
frequency.
Restriction: The period of the trigger signal must be longer than the exposure time used.
ExposureStart / SK Mode 4 (only available when camera supports integration control)
A new exposure is started exactly at the time of external triggering and the current exposure process will be inter-
rupted. The exposure time is determined by the programmed value. The exposed line will be read out with the next
external trigger. The trigger clock frequency determines the line frequency.
Restriction: The period of the trigger signal must be longer than the exposure time used.
ExposureActive / SK extSOS (Mode 5)
The exposure time and the line frequency are controlled by the external trigger signal. This affects both the start of
a new exposure (start-of-scan pulse, SOS) and the reading out of the previously exposed line.
FrameTrigger / SK FrameSync
The frame trigger synchronizes the acquisition of a 2D
area scan. The individual line scans in this area scan can
be synchronized in any of the available line trigger modes.
The camera suppresses the data transfer until a falling
edge of a TTL signal occurs at the FRAME SYNC input.
The number of lines that defines the size of the frame
must be programmed in advance.
FRAME SYNC
LINE SYNC
Video
Video Valid
Data transmission
Combined frame and line synchronization
The synchronization mode determines the timing of the line scan. Synchronization can be either performed inter-
nally or triggered by an external source, e.g. an encoder signal.
The line scan camera can be externally triggered in two different ways:
1. Line-triggered synchronization:
Each single line scan is triggered by the falling edge of a TTL signal supplied to LINE SYNC A input.
The SK6288U3KOC line scan camera facilitates advanced synchronization control by a second trigger
input LINE SYNC B. For a detailed description, see 4.2 Advanced Synchronization Control, p. 24
2. Frame-triggered synchronization:
A set of lines resulting in a 2-dimensional frame or image is triggered by the falling edge of a TTL signal
on FRAME SYNC input.
Synchronization Modes
Camera Control dialog

CCD Sensor
Scan
Object
FOV
V0
WP/ ß
WL/ ß
Pixel #1
Pixel #1
S
B
G
R
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The three lines of the implemented triple line sensor are
sensitive for the primary colors blue (B), green (G) and
red (R). For the spectral sensitivity characteristics, see
section 5 Sensor Information. The pixel width Wpis
14 µm and the line spacing WLof 112 µm is 8times the
pixel width.
During object travel, an object point reaches the blue (B)
line sensor first. If the object is translated by one pixel
height per clock pulse then after 8lines the green (G)
pixels are exposed. After another 8lines then the red (R)
pixels have been covered and all color information has
been acquired.
RGB Sensors: 2D Imaging and Pixel Allocation
A
B
Monochrome font pattern
Aline synchronous object transport
Basynchronous transport of the object
causes color convergence aberration
The Camera SK6288U3KOC outputs the blue (B),
green (G) and red (R)-information sequentially in one
single video output signal.
The color information originating from the different parts
of the object is stored in the buffer of the PC and subse-
quently reallocated correctly.
Generating the color information of object
locations for display
line scan 17
object location no. 1 2 3 ... 2096
RGB RGB RGB ... RGB
PC memory of camera data
column no. 1 2 3 4 5 6 7 8 9 ... 6288
line no.
1 R G B R G B R G B ... R G B
...
9 R G B R G B R G B ... R G B
...
17 R G B R G B R G B ... R G B
...
Triple line sensors require a precise synchronous trans-
lation of the object for the correct allocation of pixels.
Also, the transport direction has to conform to the
sequence of the line acquisition: first blue (B) then
green (G) and red (R).
Imageswithcolor convergenceaberrationsaregenerated,
when these conditions are not met.
3 Camera Control and Performing a Scan
VO:object scan velocity
WP:pixel width = pixel height HP
(for sensors with square pixels)
WL:line spacing
S: sensor length
FOV: field of view
ß: magnification = S / FOV