A device configured to perform a task. The device includes an optical sensor configured to obtain light sequences from a camera flashlight (or other source) and convert the light sequences to electronic signals; a processor configured to receive the electronic signals from the optical sensor, detect electronic signals indicative of a predefined light sequence, and output control signals in response to detection of a predefined light sequence; and a controllable feature that is activated in response to the control signals from the processor.

A light emitting diode (LED) array may include a first pixel and a second pixel on a substrate. The first pixel and the second pixel may include one or more tunnel junctions on one or more LEDs. The LED array may include a first trench between the first pixel and the second pixel. The trench may extend to the substrate.

A light emitting diode (LED) array may include a first pixel and a second pixel on a substrate. The first pixel and the second pixel may include one or more tunnel junctions on one or more LEDs. The LED array may include a first trench between the first pixel and the second pixel. The trench may extend to the substrate.

A system and method for applying a time-varying phase shift to an optical signal is described. Such a phase shift results in a frequency shift of the optical signal, which can be useful for instance in sensing applications. The design uses cross phase modulation (XPM) in a nonlinear medium such as optical fiber. The pump producing the XPM experiences a change in energy along the medium, for instance due to loss. The pump and signal have mismatched group velocities such that they walk-off each other in time, and the pump pulse repetition rate is chosen so that it has a specific relationship with respect to the walk-off. The design is compatible with very low signal loss and does not require high fidelity electrical control signals. It is capable of high-efficiency one-directional serrodyne frequency shifts, as well as producing symmetric frequency shifts. It can also be made polarization independent.

A system and method for applying a time-varying phase shift to an optical signal is described. Such a phase shift results in a frequency shift of the optical signal, which can be useful for instance in sensing applications. The design uses cross phase modulation (XPM) in a nonlinear medium such as optical fiber. The pump producing the XPM experiences a change in energy along the medium, for instance due to loss. The pump and signal have mismatched group velocities such that they walk-off each other in time, and the pump pulse repetition rate is chosen so that it has a specific relationship with respect to the walk-off. The design is compatible with very low signal loss and does not require high fidelity electrical control signals. It is capable of high-efficiency one-directional serrodyne frequency shifts, as well as producing symmetric frequency shifts. It can also be made polarization independent.

An optical transmission and reception system includes an optical transmitter including an optical modulator that optically modulates a transmission signal containing a known signal inserted at predetermined intervals and transmits it to an optical transmission line, and an optical receiver including an optical RC circuit that converts an optical modulation signal received from the optical transmission line into a complex time series signal, a photoelectric conversion element that converts the complex time series signal into an electrical intensity signal, and a digital signal processing unit that performs learning using the known signal as a teaching signal and performs demodulation, based on learning results, using the electrical intensity signal received from the photoelectric conversion element.

An optical transmission and reception system includes an optical transmitter including an optical modulator that optically modulates a transmission signal containing a known signal inserted at predetermined intervals and transmits it to an optical transmission line, and an optical receiver including an optical RC circuit that converts an optical modulation signal received from the optical transmission line into a complex time series signal, a photoelectric conversion element that converts the complex time series signal into an electrical intensity signal, and a digital signal processing unit that performs learning using the known signal as a teaching signal and performs demodulation, based on learning results, using the electrical intensity signal received from the photoelectric conversion element.

Embodiments of this application provide an OLT, an ONU, and a system. In a downlink direction, the first OLT is configured to convert received downlink data packets of M1 paths into one downlink optical signal whose wavelength is λo, and the first ONU is configured to receive the downlink optical signal, and output a target user data packet after processing the downlink optical signal. In an uplink direction, the first ONU is configured to convert received uplink data packets into an uplink optical signal whose wavelength is λi, and the first OLT is configured to receive a plurality of uplink optical signals of different wavelengths, and output user data packets of a corresponding quantity of paths after processing.

Embodiments of this application provide an OLT, an ONU, and a system. In a downlink direction, the first OLT is configured to convert received downlink data packets of M1 paths into one downlink optical signal whose wavelength is λo, and the first ONU is configured to receive the downlink optical signal, and output a target user data packet after processing the downlink optical signal. In an uplink direction, the first ONU is configured to convert received uplink data packets into an uplink optical signal whose wavelength is λi, and the first OLT is configured to receive a plurality of uplink optical signals of different wavelengths, and output user data packets of a corresponding quantity of paths after processing.

The present invention relates to a transmitter for transmitting data and for emitting electromagnetic radiation in the visible spectral range, wherein the transmitter comprises a) a radiation source for generating and emitting first electromagnetic radiation, b) a modulator being adapted to modulate the first electromagnetic radiation depending on the data to be transmitted generating modulated first electromagnetic radiation, and c) a frequency converter for converting at least a part of the modulated first electromagnetic radiation into modulated second electromagnetic radiation, said modulated second electromagnetic radiation being different from the modulated first electromagnetic radiation, wherein the frequency converter comprises a polymeric matrix material comprising at least one organic fluorescent colorant. Furthermore, the invention relates to an illumination device comprising such transmitter. Moreover, the invention relates to a data transmission system comprising such a transmitter as well as a receiver and a data analyzer.