Introduction

The CMOS sensor module (CMV4000) incorporates the following features:

resolution to 2048 x 2048 gray scale or RGB Bayer mosaic
supports window AOI mode with faster readout
programmable analog gain (0..18 dB)
progressive scan sensor (no interlaced problems!)
pipelined global shutter
programmable readout timing with free capture windows and partial scan
many trigger modes (free-running, hardware-triggered)

Details of operation

The sensor uses a pipelined global snapshot shutter, i.e. light exposure takes place on all pixels in parallel, although subsequent readout is sequential.
Therefore the sensor offers two different modes of operation:

free running mode (Overlapping exposure and readout)
snapshot mode (Sequential exposure and readout)

Free running mode

In free running mode, the sensor reaches its maximum frame rate. This is done by overlapping erase, exposure and readout phase. The sensor timing in free running mode is fixed, so there is no control when to start an acquisition. This mode is used with trigger mode Continuous.

To calculate the maximum frames per second (FPS_max) in free running mode you will need following formula (in us):

Name	Value
LVDSOutputs	16 (mvBlueCOUGAR-XD)
LVDSOutputs	2 (mvBlueCOUGAR-X)

                        129                    32    
FrameOverheadTime = ------------ * ( 20 + ------------- )
                     PixelClock            LVDSOutputs

                  129         16 * ImageHeight
ReadoutTime = ------------ * ------------------
               PixelClock       LVDSOutputs

FrameTime = FrameOverheadTime + ReadoutTime

If exposure time is lower than frame time:

            1000000
FPS_max = -----------
           FrameTime

If exposure time is greater than frame time:

                     1000000
FPS_max = ----------------------------------
           ExposureTime + FrameOverheadTime

Snapshot mode

In snapshot mode, the image acquisition process consists off several sequential phases:

Trigger

Snapshot mode starts with a trigger. This can be either a hardware or a software 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 = 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.

Line Mapping (TriggerSource Impact Acquire → Trigger Source GenICam™ (valid values for <desired Line>)):

TriggerSource Impact Acquire	TriggerSource GenICam(BCX)
GP-IN0	Line4
GP-IN1	Line5

Erase, exposure and readout

All pixels are light sensitive at the same period of time. The whole pixel core is reset simultaneously and after the exposure time all pixel values are sampled together on the storage node inside each pixel. The pixel core is read out line-by-line after exposure.

Note: Exposure and read out cycle is carry-out in serial; that causes that no exposure is possible during read out.

The step width for the exposure time is 1 us.

Image data is then shifted out line-by-line and transferred to memory.

To calculate the maximum frames per second (FPS_max) in snapshot mode you will need following formula (in us):

                129                32 + ( 16 * ImageHeight )
FrameTime = ------------ * ( 20 + --------------------------- )
             PixelClock                  LVDSOutputs

                    1000000
FPS_max =  ----------------------------
            FrameTime + ExposureTime

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.

Sensor Data

Device Structure

CMOS image sensor (Type 1")
Unit cell size: 5.5um (H) x 5.5um (V)

Characteristics

Color version

Gray scale version

Gray scale version (-X104bUV)

Device Feature And Property List

Frame rate calculator
Mode:	Overlapping exposure and readout
Pixel clock:	30 MHz (mvBlueCOUGAR-XD204b; 12 bit ADC, 4 Taps) 40 MHz (mvBlueCOUGAR-XD104b; 10 bit ADC, 16 Taps) 40 MHz (mvBlueCOUGAR-X104; 10 bit ADC, 2 Taps)
Image width:	pixels
Image height:	pixels
Exposure time:	us
Device throughput:	Device Sensor Throughput Device Link Throughput
Link speed:	Single-GigE Dual-GigE
	Extended block ID (GEV 2.x)
Network MTU (max. value of the device with the smallest MTU):
Frame rate (max):	1/s
	ExposureTime > FrameTime → FPS = 1 / ExposureTime