version 2.0 rev 18 Feb 2021
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Furthermore,LightScanPLUSoerstheusermultiplenewscanningdirectionsfortherollingshutter
mechanisminwhichbothsidesofthesensorcanbeusedsimultaneously,synchronizedtotwoscanning
lasers,thusprovidingtheoptiontoutilizethefull‘DualPortReadout’capabilityofthesensorandprovide
100 fps full resolution frame rate. These new scanning options for sCMOS are also ideal for dual-wavelength
applicationswheretwolightsourcesarescanningacrosstheimagesensorwithdierentwavelengths.The
multi-laserreadoutcongurationsareillustratedbelowinFigure35.
Figure 35: Multiple ‘dual laser’ scanning options available. The standard rolling shutter scan mode (Centre outwards in both
directionssimultaneously) is illustrated on the left along with the three additional scanning options.
For each of the various scanning options outlined above, CycleMax - a feature of LightScan PLUS – ensures
minimum dead time between scans by enabling the laser sweep and corresponding rolling shutter scan
direction to alternate from top-bottom to bottom-top, therefore avoiding the need to reset the laser for each
subsequent image. Furthermore, a programmable trigger delay has been built into LightScan Plus enabling
theusertoinputadeneddelaytimebetweenthecamerareceivinganexternaltriggerandtheacquisition
start. This is important when using peripheral devices e.g. controlling the illumination source.
2.7.7.2 FlexiScan
Flexiscanfunctionalityallowstheusertooptimizebetweentheconictingparametersofconfocality
(Exposure Window Height), frame rate (Line Scan Speed dependent) and exposure. A logical way to think
about this is; set the Exposure Window Height to achieve the degree of confocality (fewer rows gives more
backgroundhazeremoval),nextsettheLineScanSpeedtoachieveanexposuretimethatallowsyoutoget
agoodenoughsignalstrengthtoseewhatyouintendtomeasure,andnallysynchronizetheopticalscanner
speed to this resultant readout.
Table33denotesthescanspeedrangeexibilityofLightScanPLUSintermsofscanspeed.
Table 33: Global Range of Line Scan Speeds available through FlexiScan for each pixel readout rate. Also
shown is the resultant range of scan times for one full image (full top to bottom or bottom to top sweep)
and the resultant exposure range, assuming a ‘slit width’ of 10 rows.
Parameter *216 MHz *540 MHz
Line scan speed range (rows/ms)
2.98 - 41.67 7.43 - 104
Resultant scan time for one
full image (ms)
49 - 686 19.69 - 275.66
Resultant exposure range
for slit width of 10 rows (ms)
0.240 - 3.36 0.096 - 1.344
Users are advised not to input a value for line scan speed referring to a pre-selected scanning speed of the
illuminationlight,buttoadjustthescanningspeedoftheilluminationforthesynchronizationinstead.