Abstract: Disclosed is an optical probe for obtaining a micro spot light, comprising a rod-like glass body having a rectangular cross section as a core for propagating a light wave. The distal end portion of the glass body is gradually diminished toward the distal end so as to form a micro distal end face having a small diameter. The side surface of the distal end portion of the glass body in a direction perpendicular to the polarized direction of the light wave is coated with a light absorber formed of a metal film.

Abstract: This invention provides a light-emitting element that comprises a light-emitting portion made of a nitride semiconductor; and a first wavefront converter for converting the radiated shape of light that is emitted from the light-emitting portion into a radiated shape that is smaller than the wavelength thereof, and emitting the same as output light. In this case, the first wavefront converter has a small aperture of a diameter that is smaller than the wavelength of light that is emitted from the light-emitting portion. If the output light is made to comprise an evanescent wave that is emitted to the exterior through this small aperture, it is possible to obtain an extremely small light spot.

Abstract: Disclosed is a semiconductor laser device capable of minimizing the spot diameter of a laser light and also capable of improving the transmittance of light passing through a fine aperture. The semiconductor laser device comprises a light absorption film provided with a fine aperture on the outside of the light-emitting surface of the semiconductor laser element. The aperture is formed such that the aperture width W1 in a direction parallel to the polarizing direction of the laser light is smaller than half the oscillation wavelength of the semiconductor laser element, and the aperture width W2 in a direction perpendicular to the polarizing direction is larger than the aperture width W1.

Abstract: This invention provides a light-emitting element that comprises a light-emitting portion made of a nitride semiconductor; and a first wavefront converter for converting the radiated shape of light that is emitted from the light-emitting portion into a radiated shape that is smaller than the wavelength thereof, and emitting the same as output light. In this case, the first wavefront converter has a small aperture of a diameter that is smaller than the wavelength of light that is emitted from the light-emitting portion. If the output light is made to comprise an evanescent wave that is emitted to the exterior through this small aperture, it is possible to obtain an extremely small light spot.

Abstract: Disclosed is a semiconductor laser device capable of minimizing the spot diameter of a laser light and also capable of improving the transmittance of light passing through a fine aperture. The semiconductor laser device comprises a light absorption film provided with a fine aperture on the outside of the light-emitting surface of the semiconductor laser element. The aperture is formed such that the aperture width W1 in a direction parallel to the polarizing direction of the laser light is smaller than half the oscillation wavelength of the semiconductor laser element, and the aperture width W2 in a direction perpendicular to the polarizing direction is larger than the aperture width W1.

Abstract: This invention provides a light-emitting element that comprises a light-emitting portion made of a nitride semiconductor; and a first wavefront converter for converting the radiated shape of light that is emitted from the light-emitting portion into a radiated shape that is smaller than the wavelength thereof, and emitting the same as output light. In this case, the first wavefront converter has a small aperture of a diameter that is smaller than the wavelength of light that is emitted from the light-emitting portion. If the output light is made to comprise an evanescent wave that is emitted to the exterior through this small aperture, it is possible to obtain an extremely small light spot.

Abstract: Disclosed is a semiconductor laser device capable of minimizing the spot diameter of a laser light and also capable of improving the transmittance of light passing through a fine aperture. The semiconductor laser device comprises a light absorption film provided with a fine aperture on the outside of the light-emitting surface of the semiconductor laser element. The aperture is formed such that the aperture width W1 in a direction parallel to the polarizing direction of the laser light is smaller than half the oscillation wavelength of the semiconductor laser element, and the aperture width W2 in a direction perpendicular to the polarizing direction is larger than the aperture width W1.

Abstract: The control lever equipment for a bar handle vehicle enables smooth pivoting of a grip allowance adjusting mechanism for a control lever with respect to a grip. In this equipment, the control lever is composed essentially of two pieces, i.e., a lever piece and an operating piece, which pivot coaxially independent of each other on a support shaft attached to a holder fixed to the handle bar. An adjusting pin for widening and narrowing the grip allowance between the control lever and the grip of the handle bar is attached either to the lever piece or to the operating piece pivotally on an axis parallel to the support shaft. A resilient piece is interposed between the adjusting pin and a bearing for bearing the shaft end of the adjusting pin, formed either on the lever piece or the operating piece, to be coaxial with the adjusting pin.

Abstract: A semiconductor laser is disclosed, which realizes a continuous oscillation in a fundamental transverse mode at a low operating voltage by a transverse mode control. This semiconductor laser is fabricated by forming successively the following layers on a sapphire substrate 10 in the order an n-type GaN contact layer, an n-type GaAlN cladding layer 13, an MQW active layer 16, a p-type GaAlN cladding layer 19, wherein the laser comprises a double heterostructure including a ridge in the shape of a stripe formed in the cladding layer 19 and a light confining layer 20 formed in a region except the ridge portion of the cladding layer 19 on the double heterostructure, wherein a refractive index of the light confining layer 20 is larger than that of a p-type GaAlN cladding layer.

Abstract: A gallium nitride-based compound semiconductor laser has a double-heterojunction structure, in which an active layer is sandwiched between cladding layers, on a sapphire substrate. A GaN current blocking layer having a striped opening portion is formed on the p-cladding layer. A p-GaN buried layer and a contact layer through which a current is injected into the opening portion of the current blocking layer and which are larger in area than the opening portion are formed. The active layer has a multiple quantum well structure constituted by a cyclic structure formed by cyclically stacking two types of InGaAlN layers which have different band gaps and are 10 nm or less thick.

Abstract: Disclosed is an optical probe for obtaining a micro spot light, comprising a rod-like glass body having a rectangular cross section as a core for propagating an light wave. The distal end portion of the glass body is gradually diminished toward the distal end so as to form a micro distal end face having a small diameter. The side surface of the distal end portion of the glass body in a direction perpendicular to the polarized direction of the light wave is coated with a light absorber formed of a metal film.

Abstract: Disclosed is a semiconductor laser device capable of minimizing the spot diameter of a laser light and also capable of improving the transmittance of light passing through a fine aperture. The semiconductor laser device comprises a light absorption film provided with a fine aperture on the outside of the light-emitting surface of the semiconductor laser element. The aperture is formed such that the aperture width W1 in a direction parallel to the polarizing direction of the laser light is smaller than half the oscillation wavelength of the semiconductor laser element, and the aperture width W2 in a direction perpendicular to the polarizing direction is larger than the aperture width W1.

Abstract: A thermally-assisted magnetic recording head and a magnetic recording apparatus having the magnetic recording head built in are disclosed. The magnetic recording head is capable of recording magnetic information by heating a recording unit of a recording medium and raising its temperature to reduce magnetic coercive force and then applying recording magnetic field to the recording unit having the reduced coercive force. The magnetic recording head has a light absorbing film having an aperture, a laser device emitting and directing light through the aperture to the recording medium to head the recording unit and raise its temperature, and a recording magnetic pole for applying the recording magnetic field to the recording unit.

Abstract: A semiconductor laser is formed of gallium nitride series compound semiconductor and has a double hetero structure including an MQW (multiple quantum well) active layer held between p-type and n-type AlGaN clad layers. The double hetero structure is held between p-type and n-type contact layers. An InGaN optical absorption layer having an optical absorption coefficient larger than the clad layer which has the same conductivity type as the contact layer and is formed adjacent to the contact layer is formed in at least one of the contact layers and an InAlGaN optical guided mode control layer (layer of small refractive index) having an refractive index smaller than the clad layer is formed on the exterior of the optical absorption layer.

Abstract: The control lever equipment for a bar handle vehicle enables smooth pivoting of a grip allowance adjusting mechanism for a control lever with respect to a grip. In this equipment, the control lever is composed essentially of two pieces, i.e., a lever piece and an operating piece, which pivot coaxially independent of each other on a support shaft attached to a holder fixed to the handle bar. An adjusting pin for widening and narrowing the grip allowance between the control lever and the grip of the handle bar is attached either to the lever piece or to the operating piece pivotally on an axis parallel to the support shaft. A resilient piece is interposed between the adjusting pin and a bearing for bearing the shaft end of the adjusting pin, formed either on the lever piece or the operating piece, to be coaxial with the adjusting pin.

Abstract: In a nitride compound semiconductor laser including an active layer sandwiched by semiconductor layers of different conduction types on a sapphire substrate, layers of polyimide for current blocking and light confinement are formed on side surfaces of a mesa-type current confining structure with and under the p-side electrode. The laser ensures efficient, uniform carrier injection into the active layer, suppresses higher-order modes other than the fundamental transverse mode, and thereby promises a high reliability ensuring continuous pulsation under a low threshold current and a low operation voltage with low noise characteristics.

Abstract: At an n--n hetero-interface in a GaN-based or ZnSe-based multilayered semiconductor laser and light-emitting diode, an excessive voltage drop causing the operating voltage to increased is reduced, thereby lengthening the service life of the device. A single or plurality of n-type intermediate layers are provided in the n--n hetero-interface region where the excessive voltage drop develops. The excessive voltage drop developing at the n--n hetero-interface is decreased by setting the energy value at the edge of the conduction band of each intermediate layer to a mid-value between the energy values at the edges of the conduction bands of the n-type compound semiconductors adjoining both sides of the intermediate layer. The configuration of a GaN-based MQW laser including the intermediate layer formed on sapphire substrate is shown.

Abstract: In a nitride compound semiconductor light emitting device, an In.sub.0.3 Ga.sub.0.7 N/GaN multi-quantum well active layer 105 or an In.sub.0.1 Ga.sub.0.9 N/GaN multi-quantum well adjacent layer 104 is made as a saturable absorptive region so that self-pulsation occurs there. Thus, the device ensures self-pulsation with a high probability with a simple structure, and satisfies requirements for use as an optical head for reading data from an optical disc.

Abstract: A gallium nitride-based compound semiconductor laser has a double-heterojunction structure, in which an active layer is sandwiched between cladding layers, on a sapphire substrate. A GaN current blocking layer having a striped opening portion is formed on the p-cladding layer. A p-GaN buried layer and a contact layer through which a current is injected into the opening portion of the current blocking layer and which are larger in area than the opening portion are formed. The active layer has a multiple quantum well structure constituted by a cyclic structure formed by cyclically stacking two types of InGaAlN layers which have different band gaps and are 10 nm or more thick.

Abstract: There is disclosed a compound semiconductor light-emitting device of gallium nitride series having high reliability, which can be operated by a low threshold current and a low operation voltage without deterioration. The device comprises a p-type semiconductor structure having high carrier concentration, which can easily form a low resistance p-side electrode, and which can uniformly implant carriers to an active layer highly efficiently. A p electrode contact layer having Mg added thereto is used as a p-type semiconductor layer. At least a Ga.sub.x2 In.sub.y2 Al.sub.z2 N (x2+y2+z2=1, 0.ltoreq.x2, z2.ltoreq.1, 0<y2.ltoreq.1) smoothing layer is formed on an active layer than the p-type contact layer. On a surface of the p-type contact layer, there is formed a layered structure having a Pt layer, and a Ti layer containing TiN, and a Ti layer in order. An alloy, formed of Pt-semiconductor, is formed between the p-type contact layer and the Pt layer.