Map
WeChat
Email alert
RSS1992 Vol. 16, No. 2
Display Method:
1992, 16(2): 65-72.
[Abstract]
[PDF 364KB]
Abstract:
In this paper, the effect of atomospheric turbulence on laser beam propagation between tops of the high-building and the hill behind our university campus at the distance of 1500m is discussed.The typical range of measurable Cn values, curvature of the laser beam propagation and the focal spots diameter of the laser beam are given, which are agreement with the theory analysis.
In this paper, the effect of atomospheric turbulence on laser beam propagation between tops of the high-building and the hill behind our university campus at the distance of 1500m is discussed.The typical range of measurable Cn values, curvature of the laser beam propagation and the focal spots diameter of the laser beam are given, which are agreement with the theory analysis.
1992, 16(2): 72-75.
Abstract:
The Nd:YAG laser end-pumped by astigmatic diode beam is reported,for the purpose of studying diode pumped solid-state laser array. With astigmatic beam pumping, TEMn0 mode and TEM0m oscillations have been achieved, respectively, by meridianal focal plane pumping and sagittal focal plane pumping, The TEMn0 mode laser has the minium threshold of 385mW, CW output power of 320mW with 28% slope efficiency, and stable 232mW CW output power with 20% slope efficiency. The CW output stability is also described.
The Nd:YAG laser end-pumped by astigmatic diode beam is reported,for the purpose of studying diode pumped solid-state laser array. With astigmatic beam pumping, TEMn0 mode and TEM0m oscillations have been achieved, respectively, by meridianal focal plane pumping and sagittal focal plane pumping, The TEMn0 mode laser has the minium threshold of 385mW, CW output power of 320mW with 28% slope efficiency, and stable 232mW CW output power with 20% slope efficiency. The CW output stability is also described.
1992, 16(2): 76-80.
Abstract:
A new method of monitoring the in-situ extremely low residual reflectivity of antireflection (AR) coating of travelling-wave semiconductor laser amplifier (TW-SLA) is presented. The relations among the residual reflectivity, temperature and the output power of SLA are analyzed theoretically and experimentally. Minimum reflectivity less than 5×10-4 can be realized by means of using a 1.3μm InGaAsP/InP buried-hetero-structure (BH) laser diode coated with single-layer SiOx or double-lager SiOx1/SiOx2 film.
A new method of monitoring the in-situ extremely low residual reflectivity of antireflection (AR) coating of travelling-wave semiconductor laser amplifier (TW-SLA) is presented. The relations among the residual reflectivity, temperature and the output power of SLA are analyzed theoretically and experimentally. Minimum reflectivity less than 5×10-4 can be realized by means of using a 1.3μm InGaAsP/InP buried-hetero-structure (BH) laser diode coated with single-layer SiOx or double-lager SiOx1/SiOx2 film.
1992, 16(2): 81-85.
Abstract:
In this paper, a method, which has been used in real-time monitoring of laser soldering quality, based on the relation between the thermoelectrical potential and temperature of joint face of the jointed materials and the relation between the efficient heating volume (the integral of the part of the interface temperature above the temperature threshold) and the joint area, is presented. The experimental results show that the relation of the thermoelectrical potential of the jointed materials and interface temperature is well linear, the measured efficient heating volume fully shows the condition of the heating and melting of the interface and solder and can be used in monitoring and controlling laser soldering system.
In this paper, a method, which has been used in real-time monitoring of laser soldering quality, based on the relation between the thermoelectrical potential and temperature of joint face of the jointed materials and the relation between the efficient heating volume (the integral of the part of the interface temperature above the temperature threshold) and the joint area, is presented. The experimental results show that the relation of the thermoelectrical potential of the jointed materials and interface temperature is well linear, the measured efficient heating volume fully shows the condition of the heating and melting of the interface and solder and can be used in monitoring and controlling laser soldering system.
1992, 16(2): 85-88.
Abstract:
In this paper, the operating principle and software-hardware scheme of laser shooting simulator based on single-chip microcomputer are intruduced. The application result shows that the system has the advantages of simple circuits, direct display, reliable and flexible fuctions.
In this paper, the operating principle and software-hardware scheme of laser shooting simulator based on single-chip microcomputer are intruduced. The application result shows that the system has the advantages of simple circuits, direct display, reliable and flexible fuctions.
1992, 16(2): 89-93.
Abstract:
The thresholds of retinal injury of rabbit eye is experimentally determined, by means of exposing the eye to Q-switch ruby laser light. The results show that the coaglating-bleeding threshold (ED50) of retinal injury is 361μJ/cm2, the bleeding damage threshold (ED50) is 481μJ/cm2. The 95% confidence levels are 330μJ/cm2~394μJ/cm2 and 451μJ/cm2~514μJ/cm2, respectively.
The thresholds of retinal injury of rabbit eye is experimentally determined, by means of exposing the eye to Q-switch ruby laser light. The results show that the coaglating-bleeding threshold (ED50) of retinal injury is 361μJ/cm2, the bleeding damage threshold (ED50) is 481μJ/cm2. The 95% confidence levels are 330μJ/cm2~394μJ/cm2 and 451μJ/cm2~514μJ/cm2, respectively.
1992, 16(2): 93-98.
Abstract:
Theoretical study of a novel nonlinear mirror device is presented in this paper. The results indicate that laser will tend to become passively modelocked when the novel nonlinear mirror is used in the laser cavity. Parameter selection of the optimal design for the device has also been given in this paper.
Theoretical study of a novel nonlinear mirror device is presented in this paper. The results indicate that laser will tend to become passively modelocked when the novel nonlinear mirror is used in the laser cavity. Parameter selection of the optimal design for the device has also been given in this paper.
1992, 16(2): 99-104.
Abstract:
The relation between the intensity of photon echo signal and the optical delay time is derived by using the density matrix method. The application to two pulse and three pulse photon echo techniques is given. The transverse relaxation time of saturated iodine gas under regular temperature and pressure is measured experimentally by the two and three pulse photon ehco techniques, and the measurement result is about 140 ps.
The relation between the intensity of photon echo signal and the optical delay time is derived by using the density matrix method. The application to two pulse and three pulse photon echo techniques is given. The transverse relaxation time of saturated iodine gas under regular temperature and pressure is measured experimentally by the two and three pulse photon ehco techniques, and the measurement result is about 140 ps.
1992, 16(2): 105-110.
Abstract:
The basic principle and design of the data processing system of the laser threadlet measurement instrument are described in detail. With the advanced single chip computer, the system has the features, wide measurement range from 0.1mm to 10mm, high resolution (less than 1μm), low measuring error (less than 5μm), and it takes only 5ms to accomplishe each measurement. By means of the modular structure design method, the hardware and software have been constructed and the block-diagrams of the structure are shown in this paper. Finally, the error analysis and a group of measuring data are given.
The basic principle and design of the data processing system of the laser threadlet measurement instrument are described in detail. With the advanced single chip computer, the system has the features, wide measurement range from 0.1mm to 10mm, high resolution (less than 1μm), low measuring error (less than 5μm), and it takes only 5ms to accomplishe each measurement. By means of the modular structure design method, the hardware and software have been constructed and the block-diagrams of the structure are shown in this paper. Finally, the error analysis and a group of measuring data are given.
1992, 16(2): 110-116.
Abstract:
It is first to report the theoretical and expermental research results on the opto-galvanic effect (OGE) of molecule waveguide laser. Giving CO2 waveguide laser as a example, the mathematical expression of molecule opto-galvanic signal is gotten by solving the rate equation. And relation-ship between opto-galvanic signal and laser parameters is investigated by means of experimental measurement. The satisfactory agreement of theoretical analysis and experimental results shows that the molecule waveguide laser have the superior in opto-galvanic signal. Therefore, the foreground of appling OGE to stabiliting frequence of molecule waveguide laser and other domains is shown.
It is first to report the theoretical and expermental research results on the opto-galvanic effect (OGE) of molecule waveguide laser. Giving CO2 waveguide laser as a example, the mathematical expression of molecule opto-galvanic signal is gotten by solving the rate equation. And relation-ship between opto-galvanic signal and laser parameters is investigated by means of experimental measurement. The satisfactory agreement of theoretical analysis and experimental results shows that the molecule waveguide laser have the superior in opto-galvanic signal. Therefore, the foreground of appling OGE to stabiliting frequence of molecule waveguide laser and other domains is shown.
1992, 16(2): 117-122.
Abstract:
In this paper, the design thought and experimental results of a new material thermopile middle power laser meter are reported. It has the characteristics of small volume,high power density capability, high sensitivity, fast response, spectral patten smooth, accurate measurement and easy taking etc. It may be widly used in these are as such as laser laboratory, laser medicine, laser processing and outside experiments.
In this paper, the design thought and experimental results of a new material thermopile middle power laser meter are reported. It has the characteristics of small volume,high power density capability, high sensitivity, fast response, spectral patten smooth, accurate measurement and easy taking etc. It may be widly used in these are as such as laser laboratory, laser medicine, laser processing and outside experiments.
1992, 16(2): 122-125.
Abstract:
A method of measuring small laser beam divergence in accordance to the principle of the wedged plate shearing interference is presented. The results of both experiment and theoretical analysis show that the method has the accuracy of 1%, the angle resolution up to 0.01mrad, and the advantages of simplicity and wide applications.
A method of measuring small laser beam divergence in accordance to the principle of the wedged plate shearing interference is presented. The results of both experiment and theoretical analysis show that the method has the accuracy of 1%, the angle resolution up to 0.01mrad, and the advantages of simplicity and wide applications.
1992, 16(2): 125-128.
Abstract:
The mechanism of sudden change absorption loss in a sealed transverse-flow CO2 laser has been investigated. It indicates that the sudden change absorption of intracavity is caused by impurity gases released in operating laser.
The mechanism of sudden change absorption loss in a sealed transverse-flow CO2 laser has been investigated. It indicates that the sudden change absorption of intracavity is caused by impurity gases released in operating laser.
