Methods and apparatus to calibrate spatial light modulators

At least one non-transitory computer readable medium comprising instructions that, cause at least one processor to at least:

• provide a greyscale image to a spatial light modulator (SLM), the greyscale image including pixel values that cause application of corresponding voltages to individual pixels of the SLM, the pixel values arranged in a double-slit grating pattern, the SLM to produce an interference pattern based on the double-slit grating pattern;
• determine a phase difference between first and second gratings of the double-slit grating pattern based on the interference pattern;
• and
• generate a phase curvature based on the phase difference.

An apparatus comprising:

• a spatial light modulator (SLM);
• an image sensor;
• and
• processor circuitry including one or more of:
• at least one of a central processing unit, a graphic processing unit, or a digital signal processor, the at least one of the central processing unit, the graphic processing unit, or the digital signal processor having control circuitry to control data movement within the processor circuitry, arithmetic and logic circuitry to perform one or more first operations corresponding to instructions, and one or more registers to store a result of the one or more first operations, the instructions in the apparatus;
• a Field Programmable Gate Array (FPGA), the FPGA including logic gate circuitry, a plurality of configurable interconnections, and storage circuitry, the logic gate circuitry and the interconnections to perform one or more second operations corresponding to the instructions, the storage circuitry to store a result of the one or more second operations;
• or
• Application Specific Integrate Circuitry (ASIC) including logic gate circuitry to perform one or more third operations corresponding to the instructions;
• the processor circuitry to perform at least one of the first operations, the second operations or the third operations to instantiate:
• greyscale image generation circuitry to generate a greyscale image, the greyscale image to define voltages to be applied to individual pixels of the SLM, the voltages defined by pixel values in the greyscale image, the pixel values arranged in a double-slit grating pattern, the SLM to produce an interference pattern based on the double-slit grating pattern;
• interference pattern analysis circuitry to determine a phase difference between first and second gratings of the double-slit grating pattern based on the interference pattern obtained by the image sensor;
• and
• phase curvature generation circuitry to generate a phase curvature based on the phase difference.