A piece of multimode optical fiber with a low num er ical aperture (NA) is used as an inexpensive microlens to collimate the output r adiation of a laser diode bar in the high numerical aperture (NA) direction.The em...A piece of multimode optical fiber with a low num er ical aperture (NA) is used as an inexpensive microlens to collimate the output r adiation of a laser diode bar in the high numerical aperture (NA) direction.The emissions of the laser diode bar are coupled into multimode fiber array.The radi ation from individual ones of emitter regions is optically coupled into individu al ones of fiber array.Total coupling efficiency and fiber output power are 75% and 15W,respectively.展开更多
A high performance AlAs/In0.53 Ga0.47 As/InAs resonant tunneling diode （RTD） on InP substrate is fabricated by inductively coupled plasma etching. This RTD has a peak-to-valley current ratio （PVCR） of 7. 57 and a ...A high performance AlAs/In0.53 Ga0.47 As/InAs resonant tunneling diode （RTD） on InP substrate is fabricated by inductively coupled plasma etching. This RTD has a peak-to-valley current ratio （PVCR） of 7. 57 and a peak current density Jp = 39.08kA/cm^2 under forward bias at room temperature. Under reverse bias, the corresponding values are 7.93 and 34.56kA/cm^2 . A resistive cutoff frequency of 18.75GHz is obtained with the effect of a parasitic probe pad and wire. The slightly asymmetrical current-voltage characteristics with a nominally symmetrical structure are also discussed.展开更多
The output radiation from the 100μm×1μm aperture of a high power Laser Diode (LD) is efficiently coupled into a 50μm multimode optical fiber.The fiber output of the high power LD with high brightness and high ...The output radiation from the 100μm×1μm aperture of a high power Laser Diode (LD) is efficiently coupled into a 50μm multimode optical fiber.The fiber output of the high power LD with high brightness and high power density is achieved.The power density is up to 3 6×104W/cm2 and the coupling efficiency is 70%.The extreme divergence and the astigmatism of high power LDs require the optics with complex lens structures and high performance.A double-curved lens with two crossed cylindrical lenses structured on both sides of the glass substrate is used in the coupling system.展开更多
With the aim of achieving high coupling power of RWG SLDs into SMFs,the structure dependences of the output power and the near field pattern are investigated. The thicknesses of the layers between the active region an...With the aim of achieving high coupling power of RWG SLDs into SMFs,the structure dependences of the output power and the near field pattern are investigated. The thicknesses of the layers between the active region and the ridge waveguide are optimized by taking into account the injected carrier distribution and local material gain in the SLD cross section.展开更多
A novel asymmetric optothermal microactuator was developed. A microactuator of 750μm length was machined by an excimer laser micmmachining system using single layer material. It had an asymmetric structure consisting...A novel asymmetric optothermal microactuator was developed. A microactuator of 750μm length was machined by an excimer laser micmmachining system using single layer material. It had an asymmetric structure consisting of two thin expansion arms with different widths. A laser diode （660nm） was employed as the external power source to activate the microactuator. We introduced a charge coupled device （CCD）-combined optical microscope and a computer system to observe and capture the microactuator＇ s deflection and vibration. Experiments have been carried out to check the feasibility of deflection, and the data of deflection have been measured under different laser power as well as under different pulse frequency. The results show that the actuator can practically generate an obvious lateral deflection or vibration, the maximum could be larger than 20μm. Moreover, the deflection status of the microactuator could be controlled wirelessly or remotely by changing the laser power and its pulse frequency.展开更多
Beam shaping is required for semiconductor lasers to achieve high optical fiber coupling efficiency in many applications.But the positioning errors on optics may reduce beam shaping effects,and then lead to low optica...Beam shaping is required for semiconductor lasers to achieve high optical fiber coupling efficiency in many applications.But the positioning errors on optics may reduce beam shaping effects,and then lead to low optical fiber coupling efficiency.In this work,the positioning errors models for the single emitter laser diode beam shaping system are established.Moreover,the relationships between the errors and the beam shaping effect of each shapers are analysed.Subsequently,the relationship between the errors and the optical fiber coupling efficiency is analysed.The result shows that position errors in the Z axis direction on the fast axis collimator have the greatest influence on the shaping effect,followed by the position errors in the Z axis direction on the converging lens,which should be strictly suppressed in actual operation.Besides,the position errors have a significant influence on the optical fiber coupling efficiency and need to be avoided.展开更多
This paper reports a novel dual-band coupled-line bandpass filter.Comprising a quadruple-mode coupled-line resonator,this proposed filter could filter signals on two frequency bands.After introducing two varactors,one...This paper reports a novel dual-band coupled-line bandpass filter.Comprising a quadruple-mode coupled-line resonator,this proposed filter could filter signals on two frequency bands.After introducing two varactors,one of the four resonances could be continuously altered by changing the capacitance of the varactors,thus the two frequency bandwidths could be independently tunned.In this paper,the detailed explanation for its operation is given,and the agreement between the expected and practical performance sufficiently confirms the robustness and effectiveness of this proposed filter.展开更多
A low-threshold efficient high-repetition-rate eye-safe optical parametric oscillator(OPO) is presented.The OPO is based on an x-cut non-critically phase-matched(NCPM) KTA intra-cavity pumped by an acousto-optically(A...A low-threshold efficient high-repetition-rate eye-safe optical parametric oscillator(OPO) is presented.The OPO is based on an x-cut non-critically phase-matched(NCPM) KTA intra-cavity pumped by an acousto-optically(A-O) Q-switched Nd:YVO4 laser.At 10 kHz,the lowest threshold of 0.75 W and the signal power of 0.6 W are got,corresponding to the single pulse energy of 60 μJ and the peak power of 20 kW.Tuning the frequency,the maximum output power at 1536 nm is 1.03 W at 30 kHz with an optical-to-optical conversion efficiency of 12.26%.The fluctuation of the output power is 2.1% during 2 h operation.展开更多
Organic optocoupler(OOC) or organic photocoupler,optical coupler is a novel and one of the most promising organic optoelectronic devices for its well electrical isolation and anti-jamming ability in long-distance and ...Organic optocoupler(OOC) or organic photocoupler,optical coupler is a novel and one of the most promising organic optoelectronic devices for its well electrical isolation and anti-jamming ability in long-distance and real-time digital communications.The performance parameters of OOC were greatly raised during the past decade,and its development was strongly associated with basic organic devices such as organic light emitting diodes(OLED),organic photodiodes(OPD) and organic phototransistors(OPT) etc.Here we describe the principles of OOC,review recent breakthroughs in this field,and summarize the photosensor and light emitting parts which could be used in the device.Key technical points,such as current transfer ratio,frequency,matching and stability were also discussed in this paper.展开更多
文摘A piece of multimode optical fiber with a low num er ical aperture (NA) is used as an inexpensive microlens to collimate the output r adiation of a laser diode bar in the high numerical aperture (NA) direction.The emissions of the laser diode bar are coupled into multimode fiber array.The radi ation from individual ones of emitter regions is optically coupled into individu al ones of fiber array.Total coupling efficiency and fiber output power are 75% and 15W,respectively.
文摘A high performance AlAs/In0.53 Ga0.47 As/InAs resonant tunneling diode （RTD） on InP substrate is fabricated by inductively coupled plasma etching. This RTD has a peak-to-valley current ratio （PVCR） of 7. 57 and a peak current density Jp = 39.08kA/cm^2 under forward bias at room temperature. Under reverse bias, the corresponding values are 7.93 and 34.56kA/cm^2 . A resistive cutoff frequency of 18.75GHz is obtained with the effect of a parasitic probe pad and wire. The slightly asymmetrical current-voltage characteristics with a nominally symmetrical structure are also discussed.
文摘The output radiation from the 100μm×1μm aperture of a high power Laser Diode (LD) is efficiently coupled into a 50μm multimode optical fiber.The fiber output of the high power LD with high brightness and high power density is achieved.The power density is up to 3 6×104W/cm2 and the coupling efficiency is 70%.The extreme divergence and the astigmatism of high power LDs require the optics with complex lens structures and high performance.A double-curved lens with two crossed cylindrical lenses structured on both sides of the glass substrate is used in the coupling system.
文摘With the aim of achieving high coupling power of RWG SLDs into SMFs,the structure dependences of the output power and the near field pattern are investigated. The thicknesses of the layers between the active region and the ridge waveguide are optimized by taking into account the injected carrier distribution and local material gain in the SLD cross section.
基金Supported by the National High Technology Research and Development Program of China (No. 2006AA04Z237)the National Natural Science Foundation of China (No. 50775205)
文摘A novel asymmetric optothermal microactuator was developed. A microactuator of 750μm length was machined by an excimer laser micmmachining system using single layer material. It had an asymmetric structure consisting of two thin expansion arms with different widths. A laser diode （660nm） was employed as the external power source to activate the microactuator. We introduced a charge coupled device （CCD）-combined optical microscope and a computer system to observe and capture the microactuator＇ s deflection and vibration. Experiments have been carried out to check the feasibility of deflection, and the data of deflection have been measured under different laser power as well as under different pulse frequency. The results show that the actuator can practically generate an obvious lateral deflection or vibration, the maximum could be larger than 20μm. Moreover, the deflection status of the microactuator could be controlled wirelessly or remotely by changing the laser power and its pulse frequency.
基金Project(51475479) supported by the National Natural Science Foundation of ChinaProject(2017YFB1104800) supported by the National Key Research and Development Program of China+2 种基金Project(2016GK2098) supported by the Key Research and Development Program of Hunan Province,ChinaProject(ZZYJKT2017-07) supported by the State Key Laboratory of High Performance Complex Manufacturing,Central South University,ChinaProject(JMTZ201804) supported by the Key Laboratory for Precision&Non-traditional Machining of Ministry of Education,Dalian University of Technology,China
文摘Beam shaping is required for semiconductor lasers to achieve high optical fiber coupling efficiency in many applications.But the positioning errors on optics may reduce beam shaping effects,and then lead to low optical fiber coupling efficiency.In this work,the positioning errors models for the single emitter laser diode beam shaping system are established.Moreover,the relationships between the errors and the beam shaping effect of each shapers are analysed.Subsequently,the relationship between the errors and the optical fiber coupling efficiency is analysed.The result shows that position errors in the Z axis direction on the fast axis collimator have the greatest influence on the shaping effect,followed by the position errors in the Z axis direction on the converging lens,which should be strictly suppressed in actual operation.Besides,the position errors have a significant influence on the optical fiber coupling efficiency and need to be avoided.
基金supported by National Basic Research Program of China(973 Program)(No.2014CB339900)National Natural Science Foundations of China(No.61422103,and 61327806)
文摘This paper reports a novel dual-band coupled-line bandpass filter.Comprising a quadruple-mode coupled-line resonator,this proposed filter could filter signals on two frequency bands.After introducing two varactors,one of the four resonances could be continuously altered by changing the capacitance of the varactors,thus the two frequency bandwidths could be independently tunned.In this paper,the detailed explanation for its operation is given,and the agreement between the expected and practical performance sufficiently confirms the robustness and effectiveness of this proposed filter.
基金supported by the National Basic Research Development Program of China (No. 2007CB310403)the National Natural Science Foundation of China (Nos. 60801017 and 10874128)
文摘A low-threshold efficient high-repetition-rate eye-safe optical parametric oscillator(OPO) is presented.The OPO is based on an x-cut non-critically phase-matched(NCPM) KTA intra-cavity pumped by an acousto-optically(A-O) Q-switched Nd:YVO4 laser.At 10 kHz,the lowest threshold of 0.75 W and the signal power of 0.6 W are got,corresponding to the single pulse energy of 60 μJ and the peak power of 20 kW.Tuning the frequency,the maximum output power at 1536 nm is 1.03 W at 30 kHz with an optical-to-optical conversion efficiency of 12.26%.The fluctuation of the output power is 2.1% during 2 h operation.
基金supported by the National Natural Science Foundation of China (60877026 and 50990062)the National Basic Research Program of China (973Program,2009CB930602 and 2009CB623604)
文摘Organic optocoupler(OOC) or organic photocoupler,optical coupler is a novel and one of the most promising organic optoelectronic devices for its well electrical isolation and anti-jamming ability in long-distance and real-time digital communications.The performance parameters of OOC were greatly raised during the past decade,and its development was strongly associated with basic organic devices such as organic light emitting diodes(OLED),organic photodiodes(OPD) and organic phototransistors(OPT) etc.Here we describe the principles of OOC,review recent breakthroughs in this field,and summarize the photosensor and light emitting parts which could be used in the device.Key technical points,such as current transfer ratio,frequency,matching and stability were also discussed in this paper.
