A light control system is provided with a spatial light modulator of a liquid-crystal type, an input unit, and a controller. The input unit is configured to input a light to the spatial light modulator. The controller is configured to cause the spatial light modulator to function as a diffraction grating by electrically controlling the spatial light modulator. The controller is configured to change a path of a diffracted light from the spatial light modulator corresponding to the light input from the input unit by changing a shape of the diffraction grating.

A temperature compensated carrier effect switching cell controls phase shifts to compensate for phase errors induced by temperature difference between arms of the switching cell. The temperature difference may be generated by driving the carrier effect region of the switching cell. Temperature sensors within the arms of the switching cell provide signals indicative of the temperature difference.

Provided is an optical modulator in which low-voltage drive and a stable modulation characteristic are secured over a wide bandwidth. An optical modulator includes: a substrate 10; an optical waveguide (not shown) formed in the substrate 10; a modulation electrode (a signal electrode 11 and a ground electrode 12) for modulating light waves propagating through the optical waveguide; and an external signal line (not shown, only a connection connector 4 is shown) which is provided outside the substrate and supplies a modulation signal to the modulation electrode, in which an impedance value of the modulation electrode in an active region S in which an electric field formed by the modulation electrode is applied to the optical waveguide is set to be lower than an impedance value of the external signal line, and an impedance adjustment part 21 having an impedance adjustment function with respect to mainly a modulation signal in a low-frequency area and configured of a lumped-constant circuit, and an impedance matching line L having an impedance adjustment function with respect to mainly a modulation signal in a high-frequency area are disposed between the external signal line and the active region of the modulation electrode.

An intersecting splitter configured so that the branching ratio of each optical splitter differs in accordance with the difference in the number of intersections in each branched waveguide. The branching ratios (totaling 100%) of the optical splitters are adjusted so that the branching ratios on the high side as to the number of intersections is high in comparison with the branching ratios on the low side as to the number of intersections, and it is thereby possible to level the total loss.

An intersecting splitter configured so that the branching ratio of each optical splitter differs in accordance with the difference in the number of intersections in each branched waveguide. The branching ratios (totaling 100%) of the optical splitters are adjusted so that the branching ratios on the high side as to the number of intersections is high in comparison with the branching ratios on the low side as to the number of intersections, and it is thereby possible to level the total loss.

An optical beam steering device is provided that includes an input optical fiber carrying multiple input optical signals, where each input optical signal includes a unique wavelength, an arrayed waveguide grating router (AWGR) having multiple output fibers, where the input optical fiber is connected to the AWGR, distal ends of the output fibers are arranged in a two-dimensional fiber array, the input optical signals are routed by the AWGR according to each unique wavelength to a unique AWGR output fiber, and a lens, where the distal ends of the output fibers are disposed proximal to a focal plane of the lens, where for each unique position of each output fiber distal end with respect to a the lens, each input optical signal is steered at a unique angle as an output beam emitted from the lens, where changing the wavelength of the input optical signal changes the output signal angles.

The present invention discloses a PIOS with a high extinction ratio based on slab PhCs which comprises an upper slab PhC and a lower slab PhC connected as a whole; the upper slab PhC is a first square-lattice slab PhC, the unit cell of the first square-lattice slab PhC includes a high-refractive-index rotating square pillar, a single first flat dielectric pillar and a background dielectric; the first flat dielectric pillar includes a high-refractive-index dielectric pipe and a low-refractive-index dielectric, or a high-refractive-index flat films, or a low-refractive-index dielectric; the lower slab PhC is a second square-lattice slab PhC with a complete bandgap, the unit cell of said second square-lattice slab PhC includes a high-refractive-index rotating square pillar, a single second flat dielectric pillar and a background dielectric is a low-refractive-index dielectric; and an normalized frequency of the optical switch is 0.41 to 0.4167.

The present invention discloses a PIOS with a high extinction ratio based on slab PhCs which comprises an upper slab PhC and a lower slab PhC connected as a whole; the upper slab PhC is a first square-lattice slab PhC, the unit cell of the first square-lattice slab PhC includes a high-refractive-index rotating square pillar, a single first flat dielectric pillar and a background dielectric; the first flat dielectric pillar includes a high-refractive-index dielectric pipe and a low-refractive-index dielectric, or a high-refractive-index flat films, or a low-refractive-index dielectric; the lower slab PhC is a second square-lattice slab PhC with a complete bandgap, the unit cell of said second square-lattice slab PhC includes a high-refractive-index rotating square pillar, a single second flat dielectric pillar and a background dielectric is a low-refractive-index dielectric; and an normalized frequency of the optical switch is 0.41 to 0.4167.

Monitoring output power levels of a carrier-effect based switching cell allows phase errors resulting from driving a PIN or PN junction of the switching cell to be dynamically compensated for. The compensation may also allow for compensating of phase errors resulting from the phase imbalance of input couplers as well as phase errors from the waveguide due to fabrication variations. By dynamically compensating for phase errors caused by the driving of the PIN or PN junction, the extinction ratio of the carrier-effect based switching cell can be increased.

A programmable fiber-optic delay line simulates spatial distances for an environment sensor. The programmable fiber-optic delay line comprises: at least three optical transfer switches interconnected by a plurality of lengths of optical fiber, wherein the at least three optical transfer switches with the plurality of lengths of optical fiber are configured to provide a continuous delay line having a plurality of different selectable delay values, wherein the different delay values are selectable based on switch positions of the at least three optical transfer switches. A first terminal of a first optical transfer switch of the at least three optical transfer switches is connected to a third optical transfer switch of the at least three optical transfer switches, enabling bypassing of a second optical transfer switch of the at least three optical transfer switches.