National Instruments NI 17xx Acquiring Images

Chapter 5 Image Acquisition

NI 17xx Smart Camera User Manual 5-2 ni.com

can be used to calculate the maximum exposure. Assuming the object is

moving horizontally across the field of view, use Equation5-1 to calculate

the maximum exposure time.

(5-1)

where Emax is the maximum exposure time without blurring,

R is the rate of motion of the object either horizontally or

vertically,

FOV is the field of view in the direction of motion, and

N is the number of sensor pixels in the direction of motion

For many applications that include moving objects, additional lighting is

necessary to achieve good image contrast due to the short exposure time

required to avoid motion blur.

Additionally, in many environments, the ambient light conditions vary too

significantly to obtain consistent results without adding dedicated lighting.

For example, in a building with windows, the ambient light can vary

significantly with weather. Also, standard fluorescent lighting flickers at a

rate that is perceivable by the smart camera. In these situations, the ambient

light must be overridden with a dedicated light source to ensure

reproducible results.

Acquiring Images

You can configure the NI Smart Camera to acquire images based on

internal timing or an external trigger signal. In both cases, the smart camera

can acquire full frame images at the camera’s maximum frame rate.

Ifp artial scanning or binning are enabled, the smart camera can acquire

images faster than the full frame maximum frame rate. Refer to the

Maximum Frame Rate section for information about factors that affect the

maximum frame rate.

Internal Timing

The NI Smart Camera features two types of internally-timed modes:

free-run mode and fixed-frame-rate mode.

In free-run mode, the smart camera acquires images at the maximum frame

rate allowed by the configuration.

Emax

RHorizontal 2×

FOVHorizontal

()NHorizontal

()⁄

------------------------------------------------------------------------=

Contents

Main Page Important Information Warranty Copyright Trademarks Patents Compliance Compliance with FCC/Canada Radio Frequency Interference Regulations Determining FCC Class FCC/DOC Warnings Class A Contents Chapter 4 Lighting Chapter 5 Image Acquisition Chapter 6 LEDs and DIP Switches Page About This Manual Conventions Related Documentation Hardware Documents NI Vision Builder for Automated Inspection Documents LabVIEW and NI Vision Development Module Documents NI Vision Acquisition Software Documents NI Smart Camera Overview Hardware Overview Page Figure 1-1 shows the smart camera. Figure 1-1. NI Smart Camera Software Overview NI Vision Builder for Automated Inspection LabVIEW LabVIEW Real-Time Module NI Vision Development Module NI Vision Acquisition Software Power and I/O POWER-I/O Connector NI Smart Camera Power Requirements Isolated Inputs Isolated Outputs The isolated outputs can be used to drive external loads, as shown in Figures 2-3 and 2-4. Figure 2-3. Connecting an Isolated Output to a Sourcing External Load Figure 2-4. Connecting an Isolated Output to a Sinking External Load Protecting Against Inductive Loads Connecting to Serial Devices Communicating with the Console Connecting to a Quadrature Encoder Figure2 -5 shows an example of connecting the quadrature encoder differential line drivers. Figure 2-5. Connecting Differential Line Drivers Figure 2-6. NI Smart Camera Quadrature Encoder Input Circuit Figure 2-6 shows the internal quadrature encoder/RS-422 input circuit. NI Smart Camera Image Sensor Field of View Page Image Sensor Spectral Response Partial Scan Mode Binning Gain Hardware Binarization Page Lighting Lighting Connector Direct Drive Lighting Controller Page Lighting Files Selecting a Light Connecting a Light to the Direct Drive Lighting Controller External Lighting Controllers Connecting an External Lighting Controller to the NI Smart Camera Page Image Acquisition Exposure Acquiring Images Internal Timing External Trigger Page Page Maximum Frame Rate Determining the Maximum Frame Rate Determining the Scan Mode Determining the Exposure Time Determining the Lighting Mode Determining the Trigger Delay Calculating the Minimum Frame Period Page LEDs and DIP Switches Understanding the LED Indicators Device Initialization POWER LED STATUS LED Page IMG ACQ LED PASS LED FAIL LE D Configuring DIP Switches SAFE MODE Switch IP RESET Switch NO APP Switch CONSOLE Switch Ethernet Ports Ethernet LEDs ACTIVITY/LINK LED SPEED LED DHCP and Static IP Address Assignment Firewall Considerations Subnet Considerations Thermal Considerations and Mounting Thermal Considerations Mounting the NI Smart Camera Figure 8-2. Back View of the NI Smart Camera with Dimensions Figure 8-3. Front View of the NI Smart Camera with Dimensions Figure 8-4. Side View of the NI Smart Camera with Dimensions Figure 8-5. Bottom View of the NI Smart Camera with Dimensions A Specifications Power Requirements Memory Processor VGA Sensor (NI 1722/1742/1762 Only) SXGA Sensor (NI 1744/1764 Only) Page Lighting Network Serial Optically Isolated Inputs and Outputs Isolated Inputs Isolated Outputs Quadrature Encoder (NI 1742/1744/1762/1764 Only) Physical Characteristics Environmental Safety Electromagnetic Compatibility CE Compliance Environmental Management Waste Electrical and Electronic Equipment (WEEE) RoHS B Troubleshooting Configuration Problems The NI Smart Camera Does Not Appear in MAX or Vision Builder AI The NI Smart Camera Restarts Unexpectedly Run-Time Problems The NI Smart Camera is Unresponsive and Blinks the IMG ACQ and FAIL LED s Lighting Problems The Light Does Not Illuminate When Using the Direct Drive Controller There is No External Lighting Strobe MAX Vision Builder AI Triggering Problems No Trigger is Received LED Error Indications STATUS LED Error Conditions POWER LED is Not Lit When the NI Smart Camera is Powered On C Maintenance D Technical Support and Professional Services Page Glossary B C D E Page Page Page Index Numerics A B C G H I K L P Q R S T U V W