Ocean Optics Flame-S, User Manual

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6: Technical Specifications
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Pixels Read from the Flame-S via USB
Pixel Description
0
–17
Optical black pixels
18
–19
Not usable
20-2047 Optical active pixels
It is important to note that the Flame-S only digitizes the first 2048 pixels. For Flame-T, Ocean
Optics software displays 3648 pixels starting at pixel 1 above. In RS232 interface mode, the
USB4000 transmits out the first 3670 pixels.
CCD Detector Reset Operation
At the start of each integration period, the detector transfers the signal from each pixel to the
readout registers and resets the pixels. The total amount of time required to perform this
operation is ~8  9  s. The user needs to account for this time delay when the pixels are
optically inactive, especially in the external triggering modes.
Timing Signals
Strobe Signals
Single Strobe
The Single Strobe signal is a programmable TTL pulse that occurs at a user-determined time
during each integration period. This pulse has a user-defined High Transition Delay and Low
Transition Delay. The pulse width of the Single Strobe is the difference between these delays.
It is only active if the Lamp Enable command is active.
Synchronization of external devices to the spectrometer's integration period is accomplished
with this pulse. The Strobe Delay is specified by the Single Strobe High Transition Delay
(SSHTD) and the Pulse Width is specified by the Single Strobe Low Transition Delay (SSLTD)
minus the Single Strobe High Transition Delay ( PW = SSLTD – SSHTD). Both values are
programmable in 500ns increments for the range of 0 to 65,535 (32.7675ms).
The timing of the Single Strobe is based on the Start of Integration (SOI). SOI occurs on the
rising edge of
 ROG which is used to reset the Sony ILX511 detector. In all trigger modes using
an External Trigger, there is a fixed relationship between the trigger and the SOI. In the Normal
mode and Software Trigger mode, the SOI still marks the beginning of the Single Strobe, but
due to the nondeterministic timing of the software and computer operating system, this timing
will change over time and is not periodic. That is, at a constant integration time, the Single
Strobe will not be periodic, but it will indicate the start of the integration. The timing diagram
for the Single Strobe in External Hardware Trigger mode is shown below: