Boulder Nonlinear Systems (BNS) is developing Regional Look Up Tables (LUTS) to improve the accuracy of nematic SLMs.


Regional Look-Up Tables (LUTs)

Look-up tables (LUT) provide a map of pixel value (e.g., 0 to 255 for 8-bit, or 0 to 3π in phase-space) to the necessary driving voltage and are used to calibrate the SLM. Currently, a single individually calibrated LUT is shipped with every SLM. A single LUT does not represent all of the pixels in a given device with equal accuracy, however; there are spatial variations in the calibration curves. To address this, BNS has been developing algorithms to both automatically generate and incorporate Regional LUTs for improved calibration accuracy.


Regional LUT capabilities that BNS is developing:

  • Fully automated generation of a calibrated set of m × n Regional LUTs using a single photodetector
  • Fast pixel-level interpolation between the Regional LUTs using OpenCL, resulting in a LUT for each pixel