This semiconductor laser device includes a semiconductor laser chip and a spatial light modulator SLM optically coupled to the semiconductor laser chip. The semiconductor laser chip LDC includes an active layer 4, a pair of cladding layers 2 and 7 sandwiching the active layer 4, a diffraction grating layer 6 optically coupled to the active layer 4, and a drive electrode E3 that is disposed between the cladding layer 2 and the spatial light modulator SLM and supplies an electric current to the active layer 4, and the drive electrode E3 is positioned within an XY plane and has a plurality of openings as viewed from a Z-axis direction and has a non-periodic structure.

The present invention relates to a wavelength-tunable type etalon comprising a liquid crystal layer, which comprises: a first substrate; a second substrate; a reflective coating film; a transparent electrode; an alignment layer, which is independently formed while covering the opposing surface of the transparent electrode; a liquid crystal layer, which is disposed in a space between each of the alignment layer s; and a sealing member, which is provided for sealing of the liquid crystal layer; and a method for manufacturing the same.

Display devices using feedback-enhanced light emitting diodes are disclosed. The display devices include but are not limited to active and passive matrix displays and projection displays. A light emissive element disposed between feedback elements is used as light emitting element in the display devices. The light emissive element may include organic or non-organic material. The feedback elements coupled to an emissive element allow the emissive element to emit collimated light by stimulated emission. In one aspect, feedback elements that provide this function include, but are not limited to, holographic reflectors with refractive index variations that are continuous.

Display devices using feedback-enhanced light emitting diodes are disclosed. The display devices include but are not limited to active and passive matrix displays and projection displays. A light emissive element disposed between feedback elements is used as light emitting element in the display devices. The light emissive element may include organic or non-organic material. The feedback elements coupled to an emissive element allow the emissive element to emit collimated light by stimulated emission. In one aspect, feedback elements that provide this function include, but are not limited to, holographic reflectors with refractive index variations that are continuous.

In a resonator arrangement (1) including a resonator (2), an interferometer (9) is arranged inside the resonator (2) and includes at least a first and a second interferometer leg (9a, 9b). The two interferometer legs (9a, 9b) have optical path lengths (L1, L2) that differ from each other. According to the invention a splitting ratio is variably adjustable, with which the interferometer (9) splits radiation (8) circulating in the resonator (2) into the first and second interferometer legs (9a, 9b).

Display devices using feedback-enhanced light emitting diodes are disclosed. The display devices include but are not limited to active and passive matrix displays and projection displays. A light emissive element disposed between feedback elements is used as light emitting element in the display devices. The light emissive element may include organic or non-organic material. The feedback elements coupled to an emissive element allow the emissive element to emit collimated light by stimulated emission. In one aspect, feedback elements that provide this function include, but are not limited to, holographic reflectors with refractive index variations that are continuous.

A method for operating a laser device, including providing a laser pulse in a resonator so that the laser pulse circulates in the resonator, the laser pulse having a carrier wave; determining an offset frequency (f.sub.0) of the frequency comb corresponding to the laser pulse, the frequency comb having a plurality of laser modes (f.sub.m) at a distance (f.sub.rep) from one another, the frequencies of which can be described by the formula: f.sub.m=m*f.sub.rep+f.sub.0, m being a natural number, and varying the offset frequency (f.sub.0) by varying a geometric phase () that is imparted to the carrier wave of the laser pulse per resonator circulation.

The present invention relates to a method to tune a wavelength of a coherent light signal emitted by a tunable laser, the tunable laser comprising: a cavity, the cavity including: a gain medium, an optical tunable filter, a first and a second mirrors, one of which is partially reflective, wherein the optical tunable filter includes: a first and a second electrodes, a liquid crystal, the method comprising: applying a voltage difference between the first and second electrodes to apply an electric field to the liquid crystal; wherein applying a voltage difference includes: applying the voltage difference for at least a driving time interval lasting less than 1 s; and varying the voltage difference applied between the first and second electrodes within the driving time interval so that a maximum applied voltage difference is reached and said maximum applied voltage is above 0.1 kV.