Map
WeChat
Email alert
RSS1995 Vol. 19, No. 1
Display Method:
1995, 19(1): 1-5.
[Abstract]
[PDF 602KB]
Abstract:
By adding a inhomogeneous longitudinal magnetic field in the laser cavity, two kinds of the single self-stabilized-frequency He-Ne lasers have been developed.The lasers have the features of the external cavity configuration and high power out-put.Without any external frequency stabilization device, the frequency stability can reach to 6.175×10-9(τ≤10s),3.38×10-9(τ-8 (τ-8(τ<1s) for 1.8 meter laser, measured by beat frequency method.From these facts and hmogeneous extension of spectral line of high pressure gas laser, this paper analyzes the basic principles of the self-stabilized-frequency lasers and point out that this method is simple and can be widely used in the measurement devices.
By adding a inhomogeneous longitudinal magnetic field in the laser cavity, two kinds of the single self-stabilized-frequency He-Ne lasers have been developed.The lasers have the features of the external cavity configuration and high power out-put.Without any external frequency stabilization device, the frequency stability can reach to 6.175×10-9(τ≤10s),3.38×10-9(τ-8 (τ-8(τ<1s) for 1.8 meter laser, measured by beat frequency method.From these facts and hmogeneous extension of spectral line of high pressure gas laser, this paper analyzes the basic principles of the self-stabilized-frequency lasers and point out that this method is simple and can be widely used in the measurement devices.
1995, 19(1): 6-10.
Abstract:
The purpose of the paper is to introduce a coherence extender and the experimental study of the device.The extender is slanting Fabry-Perot etalon.used in the resonator of the domestic argon-ion laser.With the coherence extender,the co-herence length of argon-ion laser can come from 5cm up to several meters and the power loss is the range of 25%～40%, The device can be used in the field of coherence detection.
The purpose of the paper is to introduce a coherence extender and the experimental study of the device.The extender is slanting Fabry-Perot etalon.used in the resonator of the domestic argon-ion laser.With the coherence extender,the co-herence length of argon-ion laser can come from 5cm up to several meters and the power loss is the range of 25%～40%, The device can be used in the field of coherence detection.
1995, 19(1): 10-14.
Abstract:
This paper put forward a mathematic model of point-line combined heat conduction,shows the computer solving procedure and plotting to describe the laser deep penetration welding profile and HAZ isotherms.Using the model to analyze the various laser bead welding shapes, it is proved that the calculation results are well coin-cide with actual welding, So,the model can be used to solve the practical welding problem.
This paper put forward a mathematic model of point-line combined heat conduction,shows the computer solving procedure and plotting to describe the laser deep penetration welding profile and HAZ isotherms.Using the model to analyze the various laser bead welding shapes, it is proved that the calculation results are well coin-cide with actual welding, So,the model can be used to solve the practical welding problem.
1995, 19(1): 14-18.
Abstract:
This paper is devoted to analyze the problems of electric interconnection in VLSI,discuss the advantages of optical interconnection .The new developments of the field of optical interconnection, including guided optical interconnection and free space interconnection,are summarized.Finally, the present problems in study of optical interconnection and the way to solve these problems are suggested.
This paper is devoted to analyze the problems of electric interconnection in VLSI,discuss the advantages of optical interconnection .The new developments of the field of optical interconnection, including guided optical interconnection and free space interconnection,are summarized.Finally, the present problems in study of optical interconnection and the way to solve these problems are suggested.
1995, 19(1): 19-25.
Abstract:
The principal refractive indices and the thermal coefficients of LiNbO3 crystal doped with 5mol%MgO and 0.2mol%Ti were accurately measured at the wavelengths of 539.75nm, 632.8nm,1079.5nm and 1341.4nm,and at the tempera-tures of 288K,338K and 423K,It is straightforward to use Sellmeier's equation,modified to suite to LiNbO3 crystal,to solve the parameters Ai, Bi, Ci, and Di of Sell-meier's questions at aforesaid temperatures in an analogy manner of solving the expres-sion of parameter Ci.Then the relationship of parameters Ai,Bi,Ci and Di with tem-peratures T is obtained in terms of least-squares fit.Then the expression of thermal re-fractive index coefficients of LiNbO3 crystal can be inferred.With the expression,the thermal refractive index coefficients of Ti:Mg:LiNbO3 crystal in the wavelength and temperature ranges of 539.75nm～1341.4nm and 288K～423K can be calculated.To examine the practicability of the expression of thermal refractive index coefficients,the noncritical phase matching temperature for 1079.5nm SHG has been calculated,the differences between the calculated and experimented value is less than 1K.Therefore,the expressions are useful for design of nonlinear optical devices of using Ti:Mg:LiNbO3 crystal.
The principal refractive indices and the thermal coefficients of LiNbO3 crystal doped with 5mol%MgO and 0.2mol%Ti were accurately measured at the wavelengths of 539.75nm, 632.8nm,1079.5nm and 1341.4nm,and at the tempera-tures of 288K,338K and 423K,It is straightforward to use Sellmeier's equation,modified to suite to LiNbO3 crystal,to solve the parameters Ai, Bi, Ci, and Di of Sell-meier's questions at aforesaid temperatures in an analogy manner of solving the expres-sion of parameter Ci.Then the relationship of parameters Ai,Bi,Ci and Di with tem-peratures T is obtained in terms of least-squares fit.Then the expression of thermal re-fractive index coefficients of LiNbO3 crystal can be inferred.With the expression,the thermal refractive index coefficients of Ti:Mg:LiNbO3 crystal in the wavelength and temperature ranges of 539.75nm～1341.4nm and 288K～423K can be calculated.To examine the practicability of the expression of thermal refractive index coefficients,the noncritical phase matching temperature for 1079.5nm SHG has been calculated,the differences between the calculated and experimented value is less than 1K.Therefore,the expressions are useful for design of nonlinear optical devices of using Ti:Mg:LiNbO3 crystal.
1995, 19(1): 26-34.
Abstract:
In this paper,the development of laser measuring technique of fuel spray in recent years is reviewed.The principles,characters and problems of fuel spray of LDV(laser doppler velocimeter),PIV(particle image velocimetry), laser scattering.laser holography,laser flourescence and laser extinction method applied in the field of fuel spray experiment are introduced.Finally,the application perspective of laser measuring technique in the fuel spray is pointed out.
In this paper,the development of laser measuring technique of fuel spray in recent years is reviewed.The principles,characters and problems of fuel spray of LDV(laser doppler velocimeter),PIV(particle image velocimetry), laser scattering.laser holography,laser flourescence and laser extinction method applied in the field of fuel spray experiment are introduced.Finally,the application perspective of laser measuring technique in the fuel spray is pointed out.
1995, 19(1): 34-37.
Abstract:
Based on the theoretical analysis to birefringent filter for dye laser,this paper presents the comprehensive desigh method,discusses the tuning sensitivity, out-put power and linewidth of dye laser.
Based on the theoretical analysis to birefringent filter for dye laser,this paper presents the comprehensive desigh method,discusses the tuning sensitivity, out-put power and linewidth of dye laser.
1995, 19(1): 38-41.
Abstract:
The technique of laser Doppler velocity measurement of flow field depends on suitable selection of scattering particles.How to select the suitable scattering particles to measure the flow field with a 3-dimensional particle dynamic analyzer(3D-PDA)has been discussed in this paper.The results show that properties of scattering particles are key factors of effectiilg on the velocity measurement accurate,Thescattering particles should meet the requirements of the small size.low density,high reflective index and suitable concentration .
The technique of laser Doppler velocity measurement of flow field depends on suitable selection of scattering particles.How to select the suitable scattering particles to measure the flow field with a 3-dimensional particle dynamic analyzer(3D-PDA)has been discussed in this paper.The results show that properties of scattering particles are key factors of effectiilg on the velocity measurement accurate,Thescattering particles should meet the requirements of the small size.low density,high reflective index and suitable concentration .
1995, 19(1): 42-45.
Abstract:
In this paper,a new type of optical probe for laser digitizer.which usesthe optical scanning technology, has been developed.The probe is composed of a small semiconductor laser and a high-resolution CCD sensor.It is able to measure the surface coordinates of a model quickly and accurately to provide 3-D NC(numerical control) data, A new optical CAD software is developed to design the optical syste.With the software, one can design a superminiature laser scanning probe.
In this paper,a new type of optical probe for laser digitizer.which usesthe optical scanning technology, has been developed.The probe is composed of a small semiconductor laser and a high-resolution CCD sensor.It is able to measure the surface coordinates of a model quickly and accurately to provide 3-D NC(numerical control) data, A new optical CAD software is developed to design the optical syste.With the software, one can design a superminiature laser scanning probe.
1995, 19(1): 46-49.
Abstract:
This paper presents the results of experimental study of the Q-modulation feature of a Nd3+-doped single mode fiber laser.The system is composed of a CW Ar+ laser at wavelength of 5145 Å as a pumping source,a plane-concave optical cavity,a optical chopper as Q-switch inside cavity and a PIN detecto.With the system.Q-switch output power at wavelength 1.088μm, full width of power spectrum,relaxation..oscillation and the relationship of Q-switch feature with pumping power and chopping frequency are expermentally studied .It is useful for fiber sensor and long distance fiber communication.
This paper presents the results of experimental study of the Q-modulation feature of a Nd3+-doped single mode fiber laser.The system is composed of a CW Ar+ laser at wavelength of 5145 Å as a pumping source,a plane-concave optical cavity,a optical chopper as Q-switch inside cavity and a PIN detecto.With the system.Q-switch output power at wavelength 1.088μm, full width of power spectrum,relaxation..oscillation and the relationship of Q-switch feature with pumping power and chopping frequency are expermentally studied .It is useful for fiber sensor and long distance fiber communication.
1995, 19(1): 50-53.
Abstract:
This paper described the effect of adding Ne or Ar on N2 laser in pulsed Townsend experiment.The restults show that released primary electrons by laser pulse striked on cathode will increase 3～6 times after adding Ne or Ar N2 laser.But the pulse duration will increase 20%～25% when adding Ne,or little change when adding Ar.So,the optimum mixed ratio of Ne and Ar to be suitable to the pulsed Townsend experiment can be experimentally fined.
This paper described the effect of adding Ne or Ar on N2 laser in pulsed Townsend experiment.The restults show that released primary electrons by laser pulse striked on cathode will increase 3～6 times after adding Ne or Ar N2 laser.But the pulse duration will increase 20%～25% when adding Ne,or little change when adding Ar.So,the optimum mixed ratio of Ne and Ar to be suitable to the pulsed Townsend experiment can be experimentally fined.
1995, 19(1): 53-56.
Abstract:
In this paper,an investigation of laser remelting of ceramic-spraying coating has been summarized.In order to reduce the polosity,achieve proper mi-crostructure and homogeneity, reduce the stress in the coating layer,increase the bind-ing power of the ceramic-coating layer and substrate,the combination mechanism in phases is analyzed experimentally.This technology can be widlely used as antirot and heat-resisting substances in oil engine, steam engine, etc.
In this paper,an investigation of laser remelting of ceramic-spraying coating has been summarized.In order to reduce the polosity,achieve proper mi-crostructure and homogeneity, reduce the stress in the coating layer,increase the bind-ing power of the ceramic-coating layer and substrate,the combination mechanism in phases is analyzed experimentally.This technology can be widlely used as antirot and heat-resisting substances in oil engine, steam engine, etc.
1995, 19(1): 57-60.
Abstract:
Based on matrix optics,the relationship between maladjustment and ex-panding ratio of the laser beam expanding telescope has been analyzed in this paper.The conclusion is:a practical beam expanding telescope has maximum beam expanding ratio when its maladjustment is zero.
Based on matrix optics,the relationship between maladjustment and ex-panding ratio of the laser beam expanding telescope has been analyzed in this paper.The conclusion is:a practical beam expanding telescope has maximum beam expanding ratio when its maladjustment is zero.
1995, 19(1): 61-62.
Abstract:
1995, 19(1): 62-64.
Abstract:
Haemorrhage often happens in drawing tooth treatments, sometimes the haemorrhage is a critical thing.A Nd:YAP laser cauterization is used to stop bleeding and achieves a great success in 80 case.The ratio of once stop bleeding is high up to 100%.So,the method is a better than others.
Haemorrhage often happens in drawing tooth treatments, sometimes the haemorrhage is a critical thing.A Nd:YAP laser cauterization is used to stop bleeding and achieves a great success in 80 case.The ratio of once stop bleeding is high up to 100%.So,the method is a better than others.
