Abstract: Variable displacement compressor, with center bore 101b in a center part of cylinder block 101, includes: first bore 101b1 supporting plain bearing 131 of drive shaft 110; second bore 101b2 with a peripheral wall radially outside of first bore 101b1; and third bore 101b3 connected to a crank chamber and radially outside of a first bore 101b1. A pressure supply path 145 for flowing a part of a discharge refrigerant from a discharge chamber to the crank chamber includes: second bore 101b2; a first path 145a communicating second bore 101b2 with the discharge chamber; a second path 145b that communicates with second bore 101b2, and axially extends from one end surface of drive shaft 110 toward the inside of drive shaft 110; and a third path 145c substantially orthogonal to second path 145b and opens to an outer peripheral surface of drive shaft 110, and communicates with the crank chamber.

Abstract: A method to control a wavelength tunable laser diode (tunable LD) is disclosed. The tunable LD includes a SG-DFB region and a CSG-DBR region to tune the emission wavelength thereof. The CSG-DBR region includes three segments, where the refractive indices of respective segments are variable by heaters provided therein. When the electrical power supplied to two segments is optionally selected, the power supplied to the rest segment is corrected by an offset from a value reflecting physical dimensions of the heaters. The offset is determined such that the tunable LD shows the best side mode suppression ratio (SMSR).

Abstract: A method to control a wavelength tunable laser diode (tunable LD) is disclosed. The tunable LD includes a SG-DFB region and a CSG-DBR region to tune the emission wavelength thereof. The CSG-DBR region includes three segments, where the refractive indices of respective segments are variable by heaters provided therein. When the electrical power supplied to two segments is optionally selected, the power supplied to the rest segment is corrected by an offset from a value reflecting physical dimensions of the heaters. The offset is determined such that the tunable LD shows the best side mode suppression ratio (SMSR).

Abstract: Provided is a semiconductor laser which has a low operating current and stably oscillates even for high-temperature output. The semiconductor laser is provided with a substrate (10); an n-type clad layer (12) arranged on the substrate (10); an active layer (13) arranged on the n-type clad layer (12); a p-type clad layer (14), which is arranged on the active layer (13) and composed of a compound containing Al and has a stripe-shaped ridge structure to be a current channel; a current block layer (16), which is arranged on the surface of the p-clad layer (14) excluding an upper surface of the ridge structure and composed of a compound containing Al and has an Al composition ratio not more than that of the p-type clad layer (14); and a light absorption layer (17), which is arranged on the current block layer (16) and absorbs light at the laser oscillation wavelength.

Abstract: A method to control a wavelength tunable laser diode (tunable LD) is disclosed. The tunable LD includes a SG-DFB region and a CSG-DBR region to tune the emission wavelength thereof. The CSG-DBR region includes three segments, where the refractive indices of respective segments are variable by heaters provided therein. When the electrical power supplied to two segments is optionally selected, the power supplied to the rest segment is corrected by an offset from a value reflecting physical dimensions of the heaters. The offset is determined such that the tunable LD shows the best side mode suppression ratio (SMSR).

Abstract: Provided is a semiconductor laser which has a low operating current and stably oscillates even for high-temperature output. The semiconductor laser is provided with a substrate (10); an n-type clad layer (12) arranged on the substrate (10); an active layer (13) arranged on the n-type clad layer (12); a p-type clad layer (14), which is arranged on the active layer (13) and composed of a compound containing Al and has a stripe-shaped ridge structure to be a current channel; a current block layer (16), which is arranged on the surface of the p-clad layer (14) excluding an upper surface of the ridge structure and composed of a compound containing Al and has an Al composition ratio not more than that of the p-type clad layer (14); and a light absorption layer (17), which is arranged on the current block layer (16) and absorbs light at the laser oscillation wavelength.

Abstract: A semiconductor laser includes: a first reflector that is provided in a gain region and has a sampled grating in which a plurality of segments are combined; and a second reflector that is optically connected to the first reflector and has a sampled grating in which a plurality of segments are combined, the plurality of segments of the first reflector having a short-segment region and a long-segment region, the long-segment region having an optical length that is larger than that of the short-segment region and being positioned closer to the second reflector than at least one of the short-segment region, the optical length of the long-segment region being larger than that of the short-segment region in a range of integral multiple (n?1) plus-minus 25% of the optical length of the short-segment.

Abstract: In a swash plate type variable capacity compressor that changes a stroke of a piston by controlling the pressure of a crank chamber (6), lubrication oil contained in refrigerant gas is maximally prevented from being circulated outside the compressor. Some of discharged refrigerant gas in a discharge chamber (22) flows into the crank chamber (6) through a communication passage (25) (25a and 25b) and a control valve (27), while some of the discharged refrigerant gas flows out to a suction chamber (21) from the crank chamber (6) through a second communication passage (26) and an orifice (28), and the pressure of the crank chamber (6) is controlled through a balance between an inflow amount and an outflow amount. Oil storage chamber (30) extends downstream of the control valve (27) on the first communication passage (25) to separate oil and store the separated oil. Oil return passage (31) returns the oil stored in the oil storage chamber (30) to the crank chamber (6).

Abstract: A method to control a wavelength tunable laser diode (tunable LD) is disclosed. The tunable LD includes a SG-DFB region and a CSG-DBR region to tune the emission wavelength thereof. The CSG-DBR region includes three segments, where the refractive indices of respective segments are variable by heaters provided therein. When the electrical power supplied to two segments is optionally selected, the power supplied to the rest segment is corrected by an offset from a value reflecting physical dimensions of the heaters. The offset is determined such that the tunable LD shows the best side mode suppression ratio (SMSR).

Abstract: Variable displacement compressor, with center bore 101b in a center part of cylinder block 101, includes: first bore 101b1 supporting plain bearing 131 of drive shaft 110; second bore 101b2 with a peripheral wall radially outside of first bore 101b1; and third bore 101b3 connected to a crank chamber and radially outside of a first bore 101b1. A pressure supply path 145 for flowing a part of a discharge refrigerant from a discharge chamber to the crank chamber includes: second bore 101b2; a first path 145a communicating second bore 101b2 with the discharge chamber; a second path 145b that communicates with second bore 101b2, and axially extends from one end surface of drive shaft 110 toward the inside of drive shaft 110; and a third path 145c substantially orthogonal to second path 145b and opens to an outer peripheral surface of drive shaft 110, and communicates with the crank chamber.

Abstract: A compressor includes a cylinder block including cylinder bores and pistons within the cylinder bores. A front housing opposes a first cylinder block end face to form a crank chamber accommodating a piston driving mechanism. A valve plate opposes a second cylinder block end face and includes suction and discharge holes. A rear housing includes suction and discharge chambers and opposes the second cylinder block end face with the valve plate there between. Strap-shaped suction valves on the valve plate end face oppose the cylinder block, thereby opening and closing the suction holes at tip portions. Discharge valves on the valve plate end face oppose the rear housing to open and close the discharge holes. Through-bolts join the front housing, the crank chamber, the cylinder block, the valve plate, and the rear housing. The valve plate includes grooves extending from holes accommodating the through-bolts to portions abutting the suction valves.

Abstract: A method for tuning a semiconductor laser including a plurality of wavelength selection portions, each of which has a periodic wavelength characteristic, including: controlling a value of a refractive index controlling means of the wavelength selection portions to achieve a desired output wavelength of the laser; and shifting the value when the value is equal to or excess of a predetermined value to a basal value side until achieving the desired output wavelength, the basal value being a value without applying refractive index variation by the refractive index controlling means, the predetermined value being a value for shifting one period of the periodic wavelength characteristic.

Abstract: A semiconductor laser includes: a first reflector that is provided in a gain region and has a sampled grating in which a plurality of segments are combined; and a second reflector that is optically connected to the first reflector and has a sampled grating in which a plurality of segments are combined, the plurality of segments of the first reflector having a short-segment region and a long-segment region, the long-segment region having an optical length that is larger than that of the short-segment region and being positioned closer to the second reflector than at least one of the short-segment region, the optical length of the long-segment region being larger than that of the short-segment region in a range of integral multiple (n?1) plus-minus 25% of the optical length of the short-segment.

Abstract: Oil recirculation mechanism includes an oil separation portion (separation chamber 104b2, separation pipe 130) for separating oil from a discharged refrigerant, oil storage chamber 132 for storing the separated oil, oil return passage through which the oil storage chamber 132 communicates with the suction chamber 119, and orifice 136 with a filter. The oil storage chamber 132 extends in a diametric direction of a compressor housing and has an open end at an outer face of the housing, and the open end is occluded by an occluding member. A partition wall (bulge portion 132a), that separates the oil storage chamber 132 from the suction chamber 119, is disposed in a region more inside than the opening of the open end. An oil return passage is linearly formed through the partition wall and the orifice 136 with a filter is accommodated and positioned in the oil return passage.

Abstract: An optical semiconductor device has a semiconductor substrate, an optical semiconductor region and a heater. The optical semiconductor region is provided on the semiconductor substrate and has a width smaller than that of the semiconductor substrate. The heater is provided on the optical semiconductor region. The optical semiconductor region has a cladding region, an optical waveguide layer and a low thermal conductivity layer. The optical waveguide layer is provided in the cladding region and has a refractive index higher than that of the cladding region. The low thermal conductivity layer is provided between the optical waveguide layer and the semiconductor substrate and has a thermal conductivity lower than that of the cladding region.

Abstract: In a cylinder head 104 provided on a head side of a cylinder block 101 with a valve plate 103 interposed therebetween, a suction chamber 119 is formed on the center side and a discharge chamber 120 is formed so as to encircle the suction chamber 119. In the cylinder head 104, an oil storage chamber 132 for storing an oil separated from a discharged refrigerant by an oil separating portion (a separation pipe 130 etc.) is provided. The oil storage chamber 132 extends in the diametric direction of the cylinder head 104 integrally with the cylinder head 104 and has an open end at the outer face of the cylinder head 104, and the open end is occluded by an occluding member 134. Here, the oil storage chamber 132 has a portion bulging into the suction chamber 119.

Abstract: A method of controlling a wavelength-tunable laser selecting an oscillation wavelength with a combination of a plurality of wavelength selection portions of which wavelength peak is different from each other, comprising: a first step of confirming a control direction of the wavelength selection portion in a case where a setting value is changed from a first setting value for achieving the first wavelength to a second setting value for achieving the second wavelength; a second step of setting a setting value that is shifted from the second setting value in a direction that is opposite of a pre-determined changing direction on the wavelength selection portion as a prepared setting value, when the control direction confirmed in the first step is opposite to the pre-determined changing direction; and a third step of changing the prepared setting value set in the second step to the second setting value.

Abstract: Lubricating performance and durability of a variable capacity compressor are secured. A first communication hole 202 is formed to be close to a penetration bolt 201a at an upstream side in a rotational direction, the penetration bolt 201a is disposed outside a rotation trajectory of a rotating member such as a swash plate in a front housing 101, and a second communication hole is formed to be close to an upper penetration bolt 201b at a downstream side in a rotational direction.

Abstract: In a swash plate type variable capacity compressor that changes a stroke of a piston by controlling the pressure of a crank chamber 6, lubrication oil contained in refrigerant gas is maximally prevented from being circulated outside the compressor. Some of discharged refrigerant gas in a discharge chamber 22 flows into the crank chamber 6 through a communication passage 25 (25a and 25b) and a control valve 27, while some of the discharged refrigerant gas flows out to a suction chamber 21 from the crank chamber 6 through a second communication passage 26 and an orifice 28, and the pressure of the crank chamber 6 is controlled through a balance between an inflow amount and an outflow amount. Herein, an oil storage chamber 30 is provided, which extends at a downstream of the control valve 27 on the first communication passage 25 to separate oil and store the separated oil.

Abstract: A method of controlling a wavelength-tunable laser selecting an oscillation wavelength with a combination of a plurality of wavelength selection portions of which wavelength peak is different from each other, comprising: a first step of confirming a control direction of the wavelength selection portion in a case where a setting value is changed from a first setting value for achieving the first wavelength to a second setting value for achieving the second wavelength; a second step of setting a setting value that is shifted from the second setting value in a direction that is opposite of a pre-determined changing direction on the wavelength selection portion as a prepared setting value, when the control direction confirmed in the first step is opposite to the pre-determined changing direction; and a third step of changing the prepared setting value set in the second step to the second setting value.