Spatial light modulation device, processing device, and position estimation method

A spatial light modulation device comprising:

• a spatial light modulation unit configured to display a phase pattern used for modulating light being incident and modulates the light using the phase pattern;
• a pattern setting unit configured to set the phase pattern to be displayed on the spatial light modulation unit;
• a detection unit configured to detect light modulated by the spatial light modulation unit;
• and
• an estimation unit configured to estimate an incident position of the light onto the spatial light modulation unit, based on a detection result obtained by the detection unit,
• wherein the phase pattern being set by the pattern setting unit includes a phase pattern arranged to form a plurality of focused light spots on the detection unit by light modulated using the set phase pattern,
• the detection unit detects intensity information of the focused light spot, and
• the estimation unit estimates the incident position of the light onto the spatial light modulation unit, based on a comparison result obtained by comparing pieces of intensity information of the plurality of focused light spots detected by the detection unit.