摘要:
In a diffractive element, its grating pattern is so configured that a diffraction angle of a diffracted light beam of a light source that is subject to the first-order diffraction in a diffraction area is matched with an angle of a light beam passing through the diffractive area emitted from a light source and a light source position is matched with a light originating point of the light source that emits a light beam to be transmitted, and the center of light intensity distribution is matched with that of the light source passing through the diffractive element by inclining an optical axis of the light source. A position of the diffractive element is adjusted based on an electric current value generated when a reflected return path light beam of the light source is diffracted by the diffractive element and enters the light source.
摘要:
A linear light source (20), which emits light by causing light to propagate in a linear material (11) in which incoming light can be propagated, includes: a light emitting device (12), provided on a side of one end of the linear material (11), which emits light so that the light enters the one end of the linear material (11); and a light receiving device (21), provided on a side of the other end of the linear material (11), which detects the light which has propagated in the linear material (11). With the configuration, it is possible to provide: a linear light source in which an abnormal condition, such as breaking of a linear material, can be detected; and an electronic apparatus including the linear light source.
摘要:
A nitride semiconductor laser device has a nitride semiconductor substrate that includes a dislocation-concentrated region 102 and a wide low-dislocation region and that has the top surface thereof slanted at an angle in the range of 0.3° to 0.7° relative to the C plane and a nitride semiconductor layer laid on top thereof. The nitride semiconductor layer has a depression immediately above the dislocation-concentrated region, and has, in a region thereof other than the depression, a high-quality quantum well active layer with good flatness and without cracks, a layer that, as is grown, readily exhibits p-type conductivity, and a stripe-shaped laser light waveguide region. The laser light waveguide region is formed above the low-dislocation region. This helps realize a nitride semiconductor laser device that offers a longer life.
摘要:
A nitride semiconductor laser device with a reduction in internal crystal defects and an alleviation in stress, and a semiconductor optical apparatus comprising this nitride semiconductor laser device. First, a growth suppressing film against GaN crystal growth is formed on the surface of an n-type GaN substrate equipped with alternate stripes of dislocation concentrated regions showing a high density of crystal defects and low-dislocation regions so as to coat the dislocation concentrate regions. Next, the n-type GaN substrate coated with the growth suppressing film is overlaid with a nitride semiconductor layer by the epitaxial growth of GaN crystals. Further, the growth suppressing film is removed to adjust the lateral distance between a laser waveguide region and the closest dislocation concentrated region to 40 μm or more.
摘要:
A nitride semiconductor laser device with a reduction in internal crystal defects and an alleviation in stress, and a semiconductor optical apparatus comprising this nitride semiconductor laser device. First, a growth suppressing film against GaN crystal growth is formed on the surface of an n-type GaN substrate equipped with alternate stripes of dislocation concentrated regions showing a high density of crystal defects and low-dislocation regions so as to coat the dislocation concentrate regions. Next, the n-type GaN substrate coated with the growth suppressing film is overlaid with a nitride semiconductor layer by the epitaxial growth of GaN crystals. Further, the growth suppressing film is removed to adjust the lateral distance between a laser waveguide region and the closest dislocation concentrated region to 40 μm or more.
摘要:
The present nitride semiconductor light emitting device includes a nitride semiconductor thick film substrate and a light emitting layered structure including a plurality of nitride semiconductor layers stacked on the substrate. The nitride semiconductor substrate includes at least two layer regions including a first layer region of a high impurity concentration and a second layer region of an impurity concentration lower than the first layer region. The light emitting layered structure is formed on the first layer region of the substrate.
摘要:
The integrated optical control element of this invention includes: a first waveguide for allowing light incident from outside to propagate therein; a multilayer structure for allowing the light which has propagated in the first waveguide to be incident thereon and for transmitting the light therethrough or reflecting the light therefrom, the multilayer structure including at least one layer having a refractive index different from an equivalent refractive index of a region with which the at least one layer is in contact; and a second waveguide for receiving at least part of the light transmitted through or reflected from the multilayer structure.
摘要:
A spatial coherent light transmission apparatus according to the present invention, includes: a light transmitter for emitting a data signal as first coherent light; a light receiver for emitting second coherent light having a wavelength little different from that of The first coherent light, mixing and receiving the first and second coherent lights, and performing a coherent detection of the data signal. At least one of the light transmitter and the light receiver has a detection device for detecting at least one of a coherent light transmission state and a coherent light detection state. The apparatus further includes a control device for controlling at least one of the light transmitter and the light receiver based on information of the state detected by the detection device.
摘要:
A method for optically reading recorded information by radiating laser light emitted from a semiconductor laser which oscillates in a single longitudinal mode to an information recording medium and by detecting laser light reflected from a recording face of the information recording medium is disclosed. In the method, the optical frequency of the laser light is modulated in order that the modulated optical frequency is a periodic function dependent on time, and the absolute value of a time differential coefficient R (Hz/s) of the periodic function, a spectral line width .delta. .nu. (Hz) of the laser light, and a time period .tau. (s) from the time when the laser light is emitted to the time when the laser light reflected from the recording face of the information recording medium reaches the semiconductor laser satisfy the condition of R.gtoreq..delta. .nu./.tau.. The periodic function varies to have a sawtooth waveform or a triangular waveform.
摘要:
A semiconductor laser array device comprising a substrate with a plurality of grooves and an active layer disposed over the substrate, resulting in optical waveguides within the active layer corresponding to the grooves, wherein the grooves are disposed over the entire area of the substrate and a means for preventing the injection of current into some of the grooves that are positioned outside of the central area of the substrate is disposed whereby the other grooves positioned in the central area of the substrate consitute a laser array portion of the semiconductor laser array device.