ScanImage 2016 : Analog Input Speed for NI PXle-6341 Device

Scenario: Image 512 pixels x 512 pixels x 30 frames per second. Need to transfer ~8M values (type uint16) during galvo scanning using NI board PXIe-6341.

Characteristics: 16 analog inputs, 500 kS/s, 16-bit resolution, ±10 V

For galvo scanning you recommend the NI board PXIe-6341:

What is the relationship between the parameters 500 kS/s and 8 M uint16 values per sec?


ScanImage supports two types of scanning:

1) Scanning with two galvos for x and y (we call this LinScan).
2) Scanning with a resonant scanner in x, and a galvo in y (we call this ResScan).


LinScan: You will not be able to achieve 512x512x30Hz frame rates. Typical rates (depending on the resolution) are 0.5-5Hz


ResScan: You will be able to achieve 512x512x30Hz frame rates. There, the resonant scanner is set to a constant voltage and starts resonating (typically at 8kHz).

The Y-Galvo scans much slower than that. For a 30Hz frame rate, the galvo has to sweep over the frame once every 33.3ms. To control such a slow scan, the 900kS/s AO rate of the PXIe-6341 board are sufficient. However, to acquire the data from the PMTs, we need much faster data acquisition. In ResScan we use a NI FlexRIO FPGA (e.g. the PXIe-7961) with a high speed digitizer module (e.g. the NI-5732, which samples at 80MHz).