In an apparatus for modulating light, a spatial light modulator includes a plurality of pixels and configured to modulate input light in response to a drive voltage for each of the pixels. An input value setting unit is configured to set an input value for the each of pixels. The input value is a digital value, an entire gray level of the digital value is N, and N is a natural number. A converting unit is configured to convert the input value to a control value. A control value is a digital value, an entire gray level of the control value is M, and M is a natural number greater than N. A driving unit is configured to convert the control value to a voltage value and drive the each of the pixels in response to the drive voltage corresponding to the voltage value.

A Fourier-transform interferometer includes a phase change plate including a reflective layer configured to reflect a first light that is incident, and a meta surface configured to locally and differently change a phase of the first light that is reflected. The Fourier-transform interferometer further includes a photodetector configured to detect a second light, and a transflective mirror and a mirror configured to transmit a first part of a third light that is incident, to the phase change plate, transmit a remaining part of the third light, to the photodetector, and transmit the first light of which the phase is locally and differently changed, to the photodetector. The photodetector is further configured to detect an interference pattern between the remaining part of the third light and the first light of which the phase is locally and differently changed.

The present invention provides optical computing by means of fast Fourier transform Integration on Silicon On Insulator chip technology with implementation in the analog and temporal domain. This is done by cascading (N2) stages of delayed interferometers (couplers and phase shifters) where a parallel set of N time samples are taken and using the delay lines and phase of the optical components (constructive/deconstructive interference) the DFT is computed. The Optical Fast Fourier Transform (OFFT) design was built on passive components (22 couplers: cascaded Mach Zehnder Interferometer) used for addition and subtraction through optical interference, waveguides with short path differences are used for phase shifting and waveguides with long path differences are used for signal delay based on the needed number of outputs. Since the OFFT is a system of imbalanced interferometers, there are additional bends designed to compensate for the difference in power ratios of the arms.

A Fourier-transform interferometer includes a phase change plate including a reflective layer configured to reflect a first light that is incident, and a meta surface configured to locally and differently change a phase of the first light that is reflected. The Fourier-transform interferometer further includes a photodetector configured to detect a second light, and a transflective mirror and a mirror configured to transmit a first part of a third light that is incident, to the phase change plate, transmit a remaining part of the third light, to the photodetector, and transmit the first light of which the phase is locally and differently changed, to the photodetector. The photodetector is further configured to detect an interference pattern between the remaining part of the third light and the first light of which the phase is locally and differently changed.

In an apparatus for modulating light, a spatial light modulator includes a plurality of pixels and configured to modulate input light in response to a drive voltage for each of the pixels. An input value setting unit is configured to set an input value for the each of pixels. The input value is a digital value, an entire gray level of the digital value is N, and N is a natural number. A converting unit is configured to convert the input value to a control value. A control value is a digital value, an entire gray level of the control value is M, and M is a natural number greater than N. A driving unit is configured to convert the control value to a voltage value and drive the each of the pixels in response to the drive voltage corresponding to the voltage value.

The present invention provides optical computing by means of fast Fourier transform Integration on Silicon On Insulator chip technology with implementation in the analog and temporal domain. This is done by cascading (N2) stages of delayed interferometers (couplers and phase shifters) where a parallel set of N time samples are taken and using the delay lines and phase of the optical components (constructive/deconstructive interference) the DFT is computed. The Optical Fast Fourier Transform (OFFT) design was built on passive components (22 couplers: cascaded Mach Zehnder Interferometer) used for addition and subtraction through optical interference, waveguides with short path differences are used for phase shifting and waveguides with long path differences are used for signal delay based on the needed number of outputs. Since the OFFT is a system of imbalanced interferometers, there are additional bends designed to compensate for the difference in power ratios of the arms.

In an apparatus for modulating light, an spatial light modulator includes a plurality of pixels and configured to modulate input light in response to a drive voltage for each of the pixels. An input value setting unit is configured to set an input value for the each of pixels. The input value is a digital value, an entire gray level of the digital value is N, and N is a natural number. A converting unit is configured to convert the input value to a control value. A control value is a digital value, an entire gray level of the control value is M, and M is a natural number greater than N. A driving unit is configured to convert the control value to a voltage value and drive the each of the pixels in response to the drive voltage corresponding to the voltage value.

An optical device may include a laser emitter to generate a first laser beam and a second laser beam with orthogonal polarization states. The optical device may include first and second photodetectors to generate respective first currents based on optical powers of the first and second laser beams. The optical device may include a polarization-based beam splitter to combine the first and second laser beams. The optical device may include a wavelength filter to filter the first and second laser beams based on respective wavelengths of the first and second laser beams. The optical device may include a third photodetector and a fourth photodetector to generate respective second currents based on optical powers of the first and second laser beams after filtration. The wavelengths of the first and second laser beams may be controlled based on the first currents and the second currents.

An optical interferometer device is provided including a waveguide interferometer. The waveguide interferometer includes first and second waveguide arms in a waveguide plane, each waveguide arm including a n-type region and a p-type region forming a junction. The n-type region and the p-type region of the second waveguide arm are translationally symmetric with respect to the n-type region and the p-type region, respectively, of the first waveguide arm in the waveguide plane.

A photonic sensor including an interferometer having a first arm and a second arm including respective optical waveguides, wherein the first arm includes: at least a first coupling device for coupling a guided propagation mode of the waveguide and a free propagation mode of an ambient medium; and an optical system configured to direct the free propagation mode toward the or a second coupling device for coupling the free propagation mode of the ambient medium and a guided propagation mode of the waveguide; whereby a light wave traversing the first arm travels one portion of its path through the ambient medium.