Optical detector

A method of optical detection, the method comprising the following steps:

• modifying at least one property of a light beam in a spatially resolved fashion by using at least one spatial light modulator, the spatial light modulator having a matrix of pixels, each pixel being controllable to individually modify the at least one optical property of a portion of the light beam passing the pixel, wherein the method of controlling pixels according to any one of the preceding claims is used;
• detecting the light beam after passing the matrix of pixels of the spatial light modulator by using at least one optical sensor and for generating at least one sensor signal;
• periodically controlling at least two of the pixels with different frequencies by using at least one modulator device;
• and
• performing a frequency analysis by using at least one evaluation device and to determining signal components of the sensor signal for the control frequencies.

A modulator device for controlling pixels of at least one spatial light modulator, the spatial light modulator having a matrix of pixels, each pixel being individually controllable, the modulator device comprising:

• a) at least one receiving device adapted for receiving at least one image;
• b) at least one image segment definition device adapted for defining at least one image segment within the image;
• c) at least one gray scale value assigning device adapted for assigning at least one gray scale value to each image segment;
• d) at least one pixel assigning device adapted for assigning at least one pixel of the matrix of pixels to each image segment;
• e) at least one frequency assigning device adapted for assigning a unique modulation frequency to each gray scale value assigned to the at least one image segment;
• f) at least one controlling device adapted for controlling the at least one pixel of the matrix of pixels assigned to the at least one image segment with the unique modulation frequency assigned to the respective image segment.