Table of Contents
- mvBlueLYNX-M720a (0.3 Mpix [640 x 480])
- mvBlueLYNX-M721 (0.8 Mpix [1024 x 768])
- mvBlueLYNX-M722 (1.2 Mpix [1280 x 960])
- mvBlueLYNX-M724 (1.9 Mpix [1600 x 1200])
mvBlueLYNX-M720a (0.3 Mpix [640 x 480])
Introduction
The CCD sensor is a highly programmable imaging module which will, for example, enable the following type of applications
Industrial applications:
- triggered image acquisition with precise control of image integration start by hardware trigger input.
- image acquisition of fast moving objects due to:
- frame integration, integrating all pixels at a time in contrast to CMOS imager which typically integrate line-by-line.
- short shutter time, to get sharp images.
- flash control output to have enough light for short time.
Scientific applications:
- long time integration for low light conditions.
- optimizing image quality using the variable shutter control.
Details of operation
The process of getting an image from the CCD sensor can be separated into three different phases.
Trigger
When coming out of reset or ready with the last readout the CCD controller is waiting for a Trigger signal.
The following trigger modes are available:
| Setting (GenICam) | Mode / Setting (Device Specific) | Description |
"TriggerSelector = FrameStart" "TriggerMode = Off" | Continuous | Free running, no external trigger signal needed. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = Software" "ExposureMode = Timed" To trigger one frame execute the TriggerSoftware@i command then. | OnDemand | Image acquisition triggered by command (software trigger). |
"TriggerSelector = AcquisitionActive" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelLow" "ExposureMode = Timed" | OnLowLevel | Start an exposure of a frame as long as the trigger input is below the trigger threshold. (No FrameTrigger!) |
"TriggerSelector = AcquisitionActive" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelHigh" "ExposureMode = Timed" | OnHighLevel | Start an exposure of a frame as long as the trigger input is above the trigger threshold. (No FrameTrigger!) |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = FallingEdge" "ExposureMode = Timed" | OnFallingEdge | Each falling edge of trigger signal acquires one image. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = RisingEdge" "ExposureMode = Timed" | OnRisingEdge | Each rising edge of trigger signal acquires one image. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelHigh" "ExposureMode = TriggerWidth" | OnHighExpose | Each rising edge of trigger signal acquires one image, exposure time corresponds to pulse width. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelLow" "ExposureMode = TriggerWidth" | OnLowExpose | Each falling edge of trigger signal acquires one image, exposure time corresponds to pulse width. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = AnyEdge" "ExposureMode = Timed" | OnAnyEdge | Start the exposure of a frame when the trigger input level changes from high to low or from low to high. |
Line Mapping (TriggerSource mvIMPACT Acquire -> TriggerSource GenICam (valid values for <desired Line>)):
| TriggerSource mvIMPACT Acquire | TriggerSource GenICam(M7/BCP) |
| GP-IN0 | Line2 |
| GP-IN1 | Line3 |
- See also
- For detailed description about the trigger modes (https://www.matrix-vision/manuals/ [mvIMPACT Acquire API])
- C: TCameraTriggerMode
- C++: mvIMPACT::acquire::TCameraTriggerMode
- Note
- Trigger modes which use an external input (ctmOnLowLevel, ctmOnHighLevel, ctmOnRisingEdge, ctmOnFallingEdge) will use digital input 0 as input for the trigger signal. Input 0 is not restricted to the trigger function. It can always also be used as general purpose digital input. The input switching threshold of all inputs can be programmed with write_dac(level_in_mV). The best is to set this to the half of the input voltage. So for example if you apply a 24V switching signal to the digital inputs set the threshold to 12000 mV.
Exposure aka Integration
After an active trigger, the integration phase starts with a maximum jitter of ttrig. If flash illumination is enabled in software the flash output will be activated exactly while the sensor chip is integrating light. Exposure time is adjustable by software in increments of treadline.
Readout
When integration is finished, the image is transferred to hidden storage cells on the CCD. Image data is then shifted out line-by-line and transferred to memory. Shifting out non active lines takes tvshift, while shifting out active lines will consume treadline. The number of active pixels per line will not have any impact on readout speed.
CCD Timing
Timings
| Name | Description | Pixel clock | |
| 20 MHz | 40 MHz | ||
| ttrig | Time from trigger (internal or external) to exposure start | 3.6us | 1.8us |
| ttrans | Image transfer time (move image to readout cells in CCD) | 42.6us | 21.3us |
| treadline | time needed to readout a line | 39.05us | 19.525us |
| tvshift | time needed to shift unused lines away | 3.6us | 1.8us |
| twait | minimal time to next trigger | 7.2us | 3.6us |
| texposure | Exposure time | 1us..10s | 1us..10s |
| treadout | Image readout time (move image from readout cells to memory | treadout = (ActiveLines * treadline) + (504 - ActiveLines) * tvshift + treadline | |
- Note
- In partial scan mode (readout window ysize < 480 lines).
To calculate the maximum frames per second (FPSmax) you will need following formula (Expose mode: No overlap):
FPS_max = 1
--------------------------------------------------
t_trig + t_readout + t_exposure + t_trans + t_wait
(Expose mode: Overlapped):
t_trig + t_readout + t_trans + t_wait < t_exposure: FPS_max = 1
---------------
t_exposure
t_trig + t_readout + t_trans + t_wait > t_exposure: FPS_max = 1
-------------------------------------
t_trig + t_readout + t_trans + t_wait
Example: Frame rate as function of lines & exposure time
Now, when we insert the values using exposure time of, for example, 8000 us, 480 lines and 40MHz pixel clock (Expose mode: No overlap):
FPS_max = 1
-----------------------------------------------------------------------------------------------
1.8 us + ((480 * 19.525 us) + ((504 - 480) * 1.80 us) + 19.525 us) + 8000 us + 21.3 us + 3.6 us
= 0.0000572690945899318068 1 / us
= 57.3
Frame rate calculator
- Note
- The calculator returns the max. frame rate supported by the sensor. Please keep in mind that it will depend on the interface and the used image format if this frame rate can be transferred.
- See also
- To find out how to achieve any defined freq. below or equal to the achievable max. freq., please have a look at Achieve a defined image frequency (HRTC).
Reprogramming CCD Timing
Reprogramming the CCD Controller will happen when the following changes occur
- Changing the exposure time
- Changing the capture window
- Changing Trigger Modes
Reprogram time consists of two phases
-
Time needed to send data to the CCD controller depending on what is changed
exposure : abt 2..3ms
window: abt 4..6ms
trigger mode: from 5..90ms,
varies with oldmode/newmode combination - Time to initialize (erase) the CCD chip after reprogramming this is fixed, abt 4.5 ms
So for example when reprogramming the capture window you will need (average values)
tregprog = change_window + init_ccd
tregprog = 5ms + 4.5ms
tregprog = 9.5ms
CCD Sensor Data
Device Structure
- Interline CCD image sensor
- Image size: Diagonal 6mm (Type 1/3)
- Number of effective pixels: 659 (H) x 494 (V) approx. 330K pixels
- Total number of pixels: 692 (H) x 504 (V) approx. 350K pixels
- Chip size: 5.79mm (H) x 4.89mm (V)
- Unit cell size: 7.4um (H) x 7.4um (V)
- Optical black:
- Horizontal (H) direction: Front 2 pixels, rear 31 pixels
- Vertical (V) direction: Front 8 pixels, rear 2 pixels
- Number of dummy bits: Horizontal 16 Vertical 5
- Substrate material: Silicon
Characteristics
These zone definitions apply to both the color and gray scale version of the sensor.
Color version
Gray scale version
Device Feature And Property List
Gray scale version
Color version
mvBlueLYNX-M721 (0.8 Mpix [1024 x 768])
Introduction
The CCD sensor is a highly programmable imaging module which will, for example, enable the following type of applications
Industrial applications:
- triggered image acquisition with precise control of image exposure start by hardware trigger input.
- image acquisition of fast moving objects due to:
- frame exposure, integrating all pixels at a time in contrast to CMOS imager which typically integrate line-by-line.
- short shutter time, to get sharp images.
- flash control output to have enough light for short time.
Scientific applications:
- long time exposure for low light conditions.
- optimizing image quality using the variable shutter control.
Details of operation
The process of getting an image from the CCD sensor can be separated into three different phases.
Trigger
When coming out of reset or ready with the last readout the CCD controller is waiting for a Trigger signal.
The following trigger modes are available:
| Setting (GenICam) | Mode / Setting (Device Specific) | Description |
"TriggerSelector = FrameStart" "TriggerMode = Off" | Continuous | Free running, no external trigger signal needed. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = Software" "ExposureMode = Timed" To trigger one frame execute the TriggerSoftware@i command then. | OnDemand | Image acquisition triggered by command (software trigger). |
"TriggerSelector = AcquisitionActive" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelLow" "ExposureMode = Timed" | OnLowLevel | Start an exposure of a frame as long as the trigger input is below the trigger threshold. (No FrameTrigger!) |
"TriggerSelector = AcquisitionActive" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelHigh" "ExposureMode = Timed" | OnHighLevel | Start an exposure of a frame as long as the trigger input is above the trigger threshold. (No FrameTrigger!) |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = FallingEdge" "ExposureMode = Timed" | OnFallingEdge | Each falling edge of trigger signal acquires one image. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = RisingEdge" "ExposureMode = Timed" | OnRisingEdge | Each rising edge of trigger signal acquires one image. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelHigh" "ExposureMode = TriggerWidth" | OnHighExpose | Each rising edge of trigger signal acquires one image, exposure time corresponds to pulse width. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelLow" "ExposureMode = TriggerWidth" | OnLowExpose | Each falling edge of trigger signal acquires one image, exposure time corresponds to pulse width. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = AnyEdge" "ExposureMode = Timed" | OnAnyEdge | Start the exposure of a frame when the trigger input level changes from high to low or from low to high. |
Line Mapping (TriggerSource mvIMPACT Acquire -> TriggerSource GenICam (valid values for <desired Line>)):
| TriggerSource mvIMPACT Acquire | TriggerSource GenICam(M7/BCP) |
| GP-IN0 | Line2 |
| GP-IN1 | Line3 |
- See also
- For detailed description about the trigger modes (https://www.matrix-vision/manuals/ [mvIMPACT Acquire API])
- C: TCameraTriggerMode
- C++: mvIMPACT::acquire::TCameraTriggerMode
Exposure aka Integration
After an active trigger, the exposure phase starts with a maximum jitter of ttrig. If flash illumination is enabled in software the flash output will be activated exactly while the sensor chip is integrating light. Integration time is adjustable by software in increments of treadline.
Readout
When exposure is finished, the image is transferred to hidden storage cells on the CCD. Image data is then shifted out line-by-line and transferred to memory. Shifting out non active lines takes tvshift, while shifting out active lines will consume treadline. The number of active pixels per line will not have any impact on readout speed.
CCD Timing
Timings
| Name | Description | Pixel clock | |
| 20 MHz | 40 MHz | ||
| ttrig | Time from trigger (internal or external) to exposure start | 9.7us | 4.85us |
| ttrans | Image transfer time (move image to readout cells in CCD) | 45us | 22.5us |
| treadline | time needed to readout a line | 65.4us | 32.7us |
| tvshift | time needed to shift unused lines away | 9.7us | 4.85us |
| twait | minimal time to next trigger | 116us | 58us |
| texposure | Integration time | 1us..10s | 1us..10s |
| treadout | Image readout time (move image from readout cells to memory | treadout = (ActiveLines * treadline) + (788 - ActiveLines) * tvshift + treadline | |
- Note
- In partial scan mode (readout window ysize < 768 lines).
To calculate the maximum frames per second (FPSmax) you will need following formula (Expose mode: Sequential):
FPS_max = 1
-----------------------------------------------
t_trig + t_readout + t_exposure + t_trans + t_wait
(Expose mode: Overlapped):
t_trig + t_readout + t_trans + t_wait < t_exposure: FPS_max = 1
---------------
t_exposure
t_trig + t_readout + t_trans + t_wait > t_exposure: FPS_max = 1
-------------------------------------
t_trig + t_readout + t_trans + t_wait
Example: Frame rate as function of lines & exposure time
Now, when we insert the values using exposure time of, for example, 8000 us, 768 lines and 40MHz pixel clock (Expose mode: Sequential):
FPS_max = 1
-------------------------------------------------------------------------------------------
4.85 us + ((768 * 32.7 us) + ((788 - 768) * 4.85 us) + 32.7 us) + 8000 us + 22.5 us + 58 us
= 0.000030004215592290717 1 / us
= 30
- Note
- The calculator returns the max. frame rate supported by the sensor. Please keep in mind that it will depend on the interface and the used image format if this frame rate can be transferred.
- See also
- To find out how to achieve any defined freq. below or equal to the achievable max. freq., please have a look at Achieve a defined image frequency (HRTC).
Reprogramming CCD Timing
Reprogramming the CCD Controller will happen when the following changes occur
- Changing the exposure time
- Changing the capture window
- Changing Trigger Modes
Reprogram time consists of two phases
-
Time needed to send data to the CCD controller depending on what is changed
exposure : abt 2..3ms
window: abt 4..6ms
trigger mode: from 5..90ms,
varies with oldmode/newmode combination - Time to initialize (erase) the CCD chip after reprogramming this is fixed, abt 4.5 ms
So for example when reprogramming the capture window you will need (average values)
tregprog = change_window + init_ccd
tregprog = 5ms + 4.5ms
tregprog = 9.5ms
CCD Sensor Data
Device Structure
- Interline CCD image sensor
- Image size: Diagonal 6mm (Type 1/3)
- Number of effective pixels: 1025 (H) x 768 (V) approx. 790K pixels
- Total number of pixels: 1077 (H) x 788 (V) approx. 800K pixels
- Chip size: 5.80mm (H) x 4.92mm (V)
- Unit cell size: 4.65um (H) x 4.65um (V)
- Optical black:
- Horizontal (H) direction: Front 3 pixels, rear 40 pixels
- Vertical (V) direction: Front 7 pixels, rear 2 pixels
- Number of dummy bits: Horizontal 29 Vertical 1
- Substrate material: Silicon
Characteristics
These zone definitions apply to both the color and gray scale version of the sensor.
Color version
Gray scale version
CCD Signal Processing
The CCD signal is processed with an analog front-end and digitized by an 12 bit analog-to-digital converter (ADC). The analog front-end contains a programmable gain amplifier which is variable from 0db (gain=0) to 30dB (gain=255).
The 8 most significant bits of the ADC are captured to the frame buffer. This will give the following transfer function (based on the 8 bit digital code): Digital_code [lsb] = ccd_signal[V] * 256[lsb/V] * exp(gain[bB]/20) lsb : least significant bit (smallest digital code change)
Device Feature And Property List
Gray scale version
Color version
mvBlueLYNX-M722 (1.2 Mpix [1280 x 960])
Introduction
The CCD sensor is a highly programmable imaging module which will, for example, enable the following type of applications
Industrial applications:
- triggered image acquisition with precise control of image exposure start by hardware trigger input.
- image acquisition of fast moving objects due to:
- frame exposure, integrating all pixels at a time in contrast to CMOS imager which typically integrate line-by-line.
- short shutter time, to get sharp images.
- flash control output to have enough light for short time.
Scientific applications:
- long time exposure for low light conditions.
- optimizing image quality using the variable shutter control.
Details of operation
The process of getting an image from the CCD sensor can be separated into three different phases.
Trigger
When coming out of reset or ready with the last readout the CCD controller is waiting for a Trigger signal.
The following trigger modes are available:
| Setting (GenICam) | Mode / Setting (Device Specific) | Description |
"TriggerSelector = FrameStart" "TriggerMode = Off" | Continuous | Free running, no external trigger signal needed. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = Software" "ExposureMode = Timed" To trigger one frame execute the TriggerSoftware@i command then. | OnDemand | Image acquisition triggered by command (software trigger). |
"TriggerSelector = AcquisitionActive" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelLow" "ExposureMode = Timed" | OnLowLevel | Start an exposure of a frame as long as the trigger input is below the trigger threshold. (No FrameTrigger!) |
"TriggerSelector = AcquisitionActive" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelHigh" "ExposureMode = Timed" | OnHighLevel | Start an exposure of a frame as long as the trigger input is above the trigger threshold. (No FrameTrigger!) |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = FallingEdge" "ExposureMode = Timed" | OnFallingEdge | Each falling edge of trigger signal acquires one image. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = RisingEdge" "ExposureMode = Timed" | OnRisingEdge | Each rising edge of trigger signal acquires one image. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelHigh" "ExposureMode = TriggerWidth" | OnHighExpose | Each rising edge of trigger signal acquires one image, exposure time corresponds to pulse width. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelLow" "ExposureMode = TriggerWidth" | OnLowExpose | Each falling edge of trigger signal acquires one image, exposure time corresponds to pulse width. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = AnyEdge" "ExposureMode = Timed" | OnAnyEdge | Start the exposure of a frame when the trigger input level changes from high to low or from low to high. |
Line Mapping (TriggerSource mvIMPACT Acquire -> TriggerSource GenICam (valid values for <desired Line>)):
| TriggerSource mvIMPACT Acquire | TriggerSource GenICam(M7/BCP) |
| GP-IN0 | Line2 |
| GP-IN1 | Line3 |
- See also
- For detailed description about the trigger modes
- C: TCameraTriggerMode
- C++: mvIMPACT::acquire::TCameraTriggerMode
Exposure aka Exposure
After an active trigger, the exposure phase starts with a maximum jitter of ttrig. If flash illumination is enabled in software the flash output will be activated exactly while the sensor chip is integrating light. Exposure time is adjustable by software in increments of treadline.
Readout
When exposure is finished, the image is transferred to hidden storage cells on the CCD. Image data is then shifted out line-by-line and transferred to memory. Shifting out non active lines takes tvshift, while shifting out active lines will consume treadline. The number of active pixels per line will not have any impact on readout speed.
CCD Timing
Timings
| Name | Description | Pixel clock | |
| 20 MHz | 40 MHz | ||
| ttrig | Time from trigger (internal or external) to exposure start | 10.5us | 5.25us |
| ttrans | Image transfer time (move image to readout cells in CCD) | 29.2us | 14.6us |
| treadline | time needed to readout a line | 82.5us | 41.25us |
| tvshift | time needed to shift unused lines away | 10.5us | 5.25us |
| twait | minimal time to next trigger | 21us | 10.5us |
| texposure | Exposure time | 1us..20s | 1us..20s |
| treadout | Image readout time (move image from readout cells to memory | treadout = (ActiveLines * treadline) + (976 - ActiveLines) * tvshift + treadline | |
- Note
- In partial scan mode (readout window ysize < 964 lines).
To calculate the maximum frames per second (FPSmax) you will need following formula (Expose mode: No overlap):
FPS_max = 1
--------------------------------------------------
t_trig + t_readout + t_exposure + t_trans + t_wait
(Expose mode: Overlapped):
t_trig + t_readout + t_trans + t_wait < t_exposure: FPS_max = 1
---------------
t_exposure
t_trig + t_readout + t_trans + t_wait > t_exposure: FPS_max = 1
-------------------------------------
t_trig + t_readout + t_trans + t_wait
Example: Frame rate as function of lines & exposure time
Now, when we insert the values using exposure time of, for example, 8000 us and 964 lines in High-Speed mode (Expose mode: No overlap):
FPS_max = 1
-----------------------------------------------------------------------------------------------
5.25 us + ((964 * 41.25 us) + ((976 - 964) * 5.25 us) + 41.25 us) + 8000 us + 14.6 us + 10.5 us
= 0.000020877001060551653 1 / us
= 20.9
Frame rate calculator
- Note
- The calculator returns the max. frame rate supported by the sensor. Please keep in mind that it will depend on the interface and the used image format if this frame rate can be transferred.
- See also
- To find out how to achieve any defined freq. below or equal to the achievable max. freq., please have a look at Achieve a defined image frequency (HRTC).
Reprogramming CCD Timing
Reprogramming the CCD Controller will happen when the following changes occur
- Changing the exposure time
- Changing the capture window
- Changing Trigger Modes
Reprogram time consists of two phases
-
Time needed to send data to the CCD controller depending on what is changed
exposure : abt 2..3ms
window: abt 4..6ms
trigger mode: from 5..90ms,
varies with oldmode/newmode combination - Time to initialize (erase) the CCD chip after reprogramming this is fixed, abt 4.5 ms
So for example when reprogramming the capture window you will need (average values)
tregprog = change_window + init_ccd
tregprog = 5ms + 4.5ms
tregprog = 9.5ms
CCD Sensor Data
Device Structure
- Interline CCD image sensor
- Image size: Diagonal 6mm (Type 1/3)
- Number of effective pixels: 1296 (H) x 966 (V) approx. 1.25 M pixels
- Total number of pixels: 1348 (H) x 976 (V) approx. 1.32 M pixels
- Chip size: 6.26mm (H) x 5.01mm (V)
- Unit cell size: 3.75um (H) x 3.75um (V)
- Optical black:
- Horizontal (H) direction: Front 12 pixels, rear 40 pixels
- Vertical (V) direction: Front 8 pixels, rear 2 pixels
- Number of dummy bits: Horizontal 4 Vertical 2
- Substrate material: Silicon
Characteristics
These zone definitions apply to both the color and gray scale version of the sensor.
Color version
Gray scale version
mvBlueLYNX-M724 (1.9 Mpix [1600 x 1200])
Introduction
The CCD sensor is a highly programmable imaging module which will, for example, enable the following type of applications
Industrial applications:
- triggered image acquisition with precise control of image exposure start by hardware trigger input.
- image acquisition of fast moving objects due to:
- frame exposure, integrating all pixels at a time in contrast to CMOS imager which typically integrate line-by-line.
- short shutter time, to get sharp images.
- flash control output to have enough light for short time.
Scientific applications:
- long time exposure for low light conditions.
- optimizing image quality using the variable shutter control.
Details of operation
The process of getting an image from the CCD sensor can be separated into three different phases.
Trigger
When coming out of reset or ready with the last readout the CCD controller is waiting for a Trigger signal.
The following trigger modes are available:
| Setting (GenICam) | Mode / Setting (Device Specific) | Description |
"TriggerSelector = FrameStart" "TriggerMode = Off" | Continuous | Free running, no external trigger signal needed. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = Software" "ExposureMode = Timed" To trigger one frame execute the TriggerSoftware@i command then. | OnDemand | Image acquisition triggered by command (software trigger). |
"TriggerSelector = AcquisitionActive" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelLow" "ExposureMode = Timed" | OnLowLevel | Start an exposure of a frame as long as the trigger input is below the trigger threshold. (No FrameTrigger!) |
"TriggerSelector = AcquisitionActive" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelHigh" "ExposureMode = Timed" | OnHighLevel | Start an exposure of a frame as long as the trigger input is above the trigger threshold. (No FrameTrigger!) |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = FallingEdge" "ExposureMode = Timed" | OnFallingEdge | Each falling edge of trigger signal acquires one image. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = RisingEdge" "ExposureMode = Timed" | OnRisingEdge | Each rising edge of trigger signal acquires one image. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelHigh" "ExposureMode = TriggerWidth" | OnHighExpose | Each rising edge of trigger signal acquires one image, exposure time corresponds to pulse width. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = LevelLow" "ExposureMode = TriggerWidth" | OnLowExpose | Each falling edge of trigger signal acquires one image, exposure time corresponds to pulse width. |
"TriggerSelector = FrameStart" "TriggerMode = On" "TriggerSource = <desired Line>" "TriggerActivation = AnyEdge" "ExposureMode = Timed" | OnAnyEdge | Start the exposure of a frame when the trigger input level changes from high to low or from low to high. |
Line Mapping (TriggerSource mvIMPACT Acquire -> TriggerSource GenICam (valid values for <desired Line>)): 1500
| TriggerSource mvIMPACT Acquire | TriggerSource GenICam(M7/BCP) |
| GP-IN0 | Line2 |
| GP-IN1 | Line3 |
- See also
- For detailed description about the trigger modes (https://www.matrix-vision/manuals/ [mvIMPACT Acquire API])
- C: TCameraTriggerMode
- C++: mvIMPACT::acquire::TCameraTriggerMode
Exposure aka Integration
After an active trigger, the exposure phase starts with a maximum jitter of ttrig. If flash illumination is enabled in software the flash output will be activated exactly while the sensor chip is integrating light. Exposure time is adjustable by software in increments of treadline.
Readout
When exposure is finished, the image is transferred to hidden storage cells on the CCD. Image data is then shifted out line-by-line and transferred to memory. Shifting out non active lines takes tvshift, while shifting out active lines will consume treadline. The number of active pixels per line will not have any impact on readout speed.
CCD Timing
Timings
| Name | Description | Pixel clock | |
| 20 MHz | 40 MHz | ||
| ttrig | Time from trigger (internal or external) to exposure start | 10.2us | 5.1us |
| ttrans | Image transfer time (move image to readout cells in CCD) | 96us | 48us |
| treadline | time needed to readout a line | 96us | 48us |
| tvshift | time needed to shift unused lines away | 10.2us | 5.1us |
| twait | minimal time to next trigger | 316us | 158us |
| texposure | Exposure time | 1us..10s | 1us..10s |
| treadout | Image readout time (move image from readout cells to memory | treadout = (ActiveLines * treadline) + (1248 - ActiveLines) * tvshift + treadline | |
- Note
- In partial scan mode (readout window ysize < 1200 lines).
To calculate the maximum frames per second (FPSmax) you will need following formula (Expose mode: No overlap):
FPS_max = 1
--------------------------------------------------
t_trig + t_readout + t_exposure + t_trans + t_wait
(Expose mode: Overlapped):
t_trig + t_readout + t_trans + t_wait < t_exposure: FPS_max = 1
---------------
t_exposure
t_trig + t_readout + t_trans + t_wait > t_exposure: FPS_max = 1
-------------------------------------
t_trig + t_readout + t_trans + t_wait
Example: Frame rate as function of lines & exposure time
Now, when we insert the values using exposure time of, for example, 8000 us, 1200 lines and 40MHz pixel clock (Expose mode: No overlap):
FPS_max = 1
---------------------------------------------------------------------------------------
5.1 us + ((1200 * 48 us) + ((1248 - 1200) * 5.1 us) + 48 us) + 8000 us + 48 us + 158 us
= 0.000015127700483632586 1 / us
= 15.1
Frame rate calculator
- Note
- The calculator returns the max. frame rate supported by the sensor. Please keep in mind that it will depend on the interface and the used image format if this frame rate can be transferred.
- See also
- To find out how to achieve any defined freq. below or equal to the achievable max. freq., please have a look at Achieve a defined image frequency (HRTC).
Reprogramming CCD Timing
Reprogramming the CCD Controller will happen when the following changes occur
- Changing the exposure time
- Changing the capture window
- Changing Trigger Modes
Reprogram time consists of two phases
- Time needed to send data to the CCD controller depending on what is changed exposure : abt 2..3ms window: abt 4..6ms trigger mode: from 5..90ms, varies with oldmode/newmode combination
- Time to initialize (erase) the CCD chip after reprogramming this is fixed, abt 4.5 ms
So for example when reprogramming the capture window you will need (average values)
tregprog = change_window + init_ccd
tregprog = 5ms + 4.5ms
tregprog = 9.5ms
CCD Sensor Data
Device Structure
- Interline CCD image sensor
- Image size: Diagonal 8.923mm (Type 1/1.8)
- Number of effective pixels: 1600 (H) x 1200 (V) approx. 1.92M pixels
- Total number of pixels: 1688 (H) x 1248 (V) approx. 2.11M pixels
- Chip size: 8.50mm (H) x 6.8mm (V)
- Unit cell size: 4.4um (H) x 4.4um (V)
- Optical black:
- Horizontal (H) direction: Front 12 pixels, rear 48 pixels
- Vertical (V) direction: Front 10 pixels, rear 2 pixels
- Number of dummy bits: Horizontal 28 Vertical 1
- Substrate material: Silicon
Characteristics
These zone definitions apply to both the color and gray scale version of the sensor.
Color version
Gray scale version
CCD Signal Processing
The CCD signal is processed with an analog front-end and digitized by an 12 bit analog-to-digital converter (ADC). The analog front-end contains a programmable gain amplifier which is variable from 0db (gain=0) to 30dB (gain=255).
The 8 most significant bits of the ADC are captured to the frame buffer. This will give the following transfer function (based on the 8 bit digital code): Digital_code [lsb] = ccd_signal[V] * 256[lsb/V] * exp(gain[bB]/20) lsb : least significant bit (smallest digital code change)
