Hi,
I'm using LabVIEW 2020, PCI-6602, BNC-2121, Hamamatsu 6420 photon counting module, and a Texas Instruments DLP4500 digital micromirror device (DMD) as a structured light detection system. Light from a microscope is reflected from the DMD onto a photon counting photomultiplier tube (PMT). I've combined IMAQ Create, IMAQ WindDraw, and Photon count with dwell time to create a VI which modulates the DMD by displaying an image (similar to how a projector operates as a second screen) and recording the photon counts of the reflection of light from that image. I am troubleshooting the device by alternating the DMD mirrors to all "ON" and then all "OFF" ( by displaying black and white images) and recording the photon counts. As you can see by the data, occasionally I get the PMT still reading from the previous loop (or a delay from IMAQ?), which creates a mixed reading of ON and OFF states. In this measurement I took 4 samples and threw the first one away at 100 ms per data point. I get fewer of these "hang ups" by taking and deleting more samples, but the issue persist and it is detrimental to image reconstruction and significantly increases measurement times. This shows that even after >400 ms that the counter is still counting the photons from the previous image or that there is a delay in the image swap with IMAQ. I would like to solve why I get an occasional lag from the DAQ system which throws off my readings. This might be my counter, VI, or Vision systems fault so I appreciate any suggestions.
Thank you,
Dillon Kopecky