The modulation transfer spectroscopy in an ytterbium hollow cathode lamp at 399 nm is measured. The error signal for frequency locking is optimized by measuring the dependences of its slope, linewidth and magnitude on...The modulation transfer spectroscopy in an ytterbium hollow cathode lamp at 399 nm is measured. The error signal for frequency locking is optimized by measuring the dependences of its slope, linewidth and magnitude on various parameters. Under the optimum condition, the laser frequency at 399 nm can be stabilized. The long-term stability of laser frequency is measured by monitoring the fluorescence signal of the ytterbium atomic beam induced by the locked laser. The laser frequency is shown to be tightly locked, and the stabilized laser is successfully applied to the cooling of ytterbium atoms.展开更多
Vacuum space between Ar atoms in unlighted HCFL lamps is an electric insulator, because vacuum fills up with strong negative electric field from orbital electrons in 3p6 electron shell of Ar atoms. Vacuum space in lig...Vacuum space between Ar atoms in unlighted HCFL lamps is an electric insulator, because vacuum fills up with strong negative electric field from orbital electrons in 3p6 electron shell of Ar atoms. Vacuum space in lighted FL lamps changes to the neutral vacuum that provides a superconductive vacuum for moving electrons at above room temperature. The complications of lighting mechanisms of HCFL lamps for more than 80 years have clearly solved with coexistence of disparate external and internal electric circuits for each half cycle. External electric circuit acts as two roles. One helps for formation of internal electric circuit in Ar gas space by electric field. Other picks up induced voltages from capacitor CFL. HCFL lamp only lights up with moving electrons in internal DC driving circuit. Electrons in HCFL lamp only move from cathode to anode, which respectively have negative and positive potentials against grand (V = 0), and which are formed with volumes of heated corona light (4G) at around W-filament metal electrodes with a help of heated BaO particles. The HCFL lamp that emits thermoelectrons is a false story. Here we have totally revised the fundamentals of the lighting mechanism of the established HCFL lamps for last 80 years.展开更多
The effect of an axial magnetic field （AMF） on an old xenon short-arc lamp is experimentally investigated in this work. As the AMF increases up to 18 roT, the visible radiation power and electric power ascend more t...The effect of an axial magnetic field （AMF） on an old xenon short-arc lamp is experimentally investigated in this work. As the AMF increases up to 18 roT, the visible radiation power and electric power ascend more than 80% and 70% respectively, and the radiation efficiency is improved by 23% for the best increment at 12 mT AMF. The measurement of radiation intensity shows that the increment of radiation intensity comes mostly from the plasma area close to the cathode tip, and partially from the other area of the arc column. Successive images of the arc indicate that the arc column not only rotates about its axis, but revolves around the axis of electrodes with the AMF. The arc column structure is constricted, distorted and elongated as the AMF increases. It is suggested that the improvements of the radiation intensity and radiation efficiency are attributed to the constriction of the arc column, which is mainly induced by the enhanced cathode jet.展开更多
PSPICE model driven by an electric equivalent circuit of a piezoelectric circuit is presented. In order to confirm this model to be effective, an independent model of cold cathode fluorescent lamp(CCFL) driving circui...PSPICE model driven by an electric equivalent circuit of a piezoelectric circuit is presented. In order to confirm this model to be effective, an independent model of cold cathode fluorescent lamp(CCFL) driving circuit is used to conduct simulations, leading to a precise modeling. A library is configured through modeling and its accuracy is verified through simulations for widely used and representative lamps such as CCFL, fluorescent lamps, HID lamps, and electrodeless fluorescent lamps. On the basis of experiments, a lamp simulation is also performed using PSPICE, which allows us to take advantage of the lamp library easily. Also, PSPICE model driven by an electric equivalent circuit of a piezoelectric transformer is presented. In order to confirm this model to be effective, an independent model of CCFL driving circuit is used to conduct simulations, leading to a precise modeling. In addition, a new type of electronic ballast is proposed, which allows 35 W-class(T5-class) fluorescent lamp to work. This system is built by a rectifier which has improved power factor and half-bridge series resonant inverter. Also, with size of 27.5 mm high, 27.5 mm wide and 2.5 mm thick, the produced piezoelectric transformer has a high step-up ratio, through which it is possible for the electric ballast circuit to be lighter, smaller and more efficient. After the produced ballast is used to drive the fluorescent lamp for 25 min, it yields 0.95 in power factor correction, 86% in efficiency, 35.07 W in output voltage and 20.5 °C in temperature increase while meeting the characteristics of the 35 W-class fluorescent lamp.展开更多
The intensities of fluorescence spectral lines of Ca atoms and Sr atoms in two different hollow cathode lamps （HCLs） are measured by element-balance-detection technology. In the wavelength range of 350–750 nm in th...The intensities of fluorescence spectral lines of Ca atoms and Sr atoms in two different hollow cathode lamps （HCLs） are measured by element-balance-detection technology. In the wavelength range of 350–750 nm in the visible spectral region, using the individual strongest line （Ca 422.67 nm, Sr 460.73 nm） as the bench mark, the population ratios between the excited states of Ca atoms and Sr atoms are calculated by rate equations and the spontaneous transition probabilities. The HCLs with populations at excited states can be used to realize the frequency stabilization reference of the laser frequency standard.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.10774044)the National Key Basic Research and Development Program of China(Grant No.2010CB922903)+1 种基金the Science and Technology Commission of Shanghai Municipality of China(Grant No.07JC14019)Shanghai Pujiang Talent Program of China(Grant No.07PJ14038)
文摘The modulation transfer spectroscopy in an ytterbium hollow cathode lamp at 399 nm is measured. The error signal for frequency locking is optimized by measuring the dependences of its slope, linewidth and magnitude on various parameters. Under the optimum condition, the laser frequency at 399 nm can be stabilized. The long-term stability of laser frequency is measured by monitoring the fluorescence signal of the ytterbium atomic beam induced by the locked laser. The laser frequency is shown to be tightly locked, and the stabilized laser is successfully applied to the cooling of ytterbium atoms.
文摘Vacuum space between Ar atoms in unlighted HCFL lamps is an electric insulator, because vacuum fills up with strong negative electric field from orbital electrons in 3p6 electron shell of Ar atoms. Vacuum space in lighted FL lamps changes to the neutral vacuum that provides a superconductive vacuum for moving electrons at above room temperature. The complications of lighting mechanisms of HCFL lamps for more than 80 years have clearly solved with coexistence of disparate external and internal electric circuits for each half cycle. External electric circuit acts as two roles. One helps for formation of internal electric circuit in Ar gas space by electric field. Other picks up induced voltages from capacitor CFL. HCFL lamp only lights up with moving electrons in internal DC driving circuit. Electrons in HCFL lamp only move from cathode to anode, which respectively have negative and positive potentials against grand (V = 0), and which are formed with volumes of heated corona light (4G) at around W-filament metal electrodes with a help of heated BaO particles. The HCFL lamp that emits thermoelectrons is a false story. Here we have totally revised the fundamentals of the lighting mechanism of the established HCFL lamps for last 80 years.
基金supported by National Natural Science Foundation of China (Nos.50876101,11035005)the Science Instrument Foundation of CAS
文摘The effect of an axial magnetic field （AMF） on an old xenon short-arc lamp is experimentally investigated in this work. As the AMF increases up to 18 roT, the visible radiation power and electric power ascend more than 80% and 70% respectively, and the radiation efficiency is improved by 23% for the best increment at 12 mT AMF. The measurement of radiation intensity shows that the increment of radiation intensity comes mostly from the plasma area close to the cathode tip, and partially from the other area of the arc column. Successive images of the arc indicate that the arc column not only rotates about its axis, but revolves around the axis of electrodes with the AMF. The arc column structure is constricted, distorted and elongated as the AMF increases. It is suggested that the improvements of the radiation intensity and radiation efficiency are attributed to the constriction of the arc column, which is mainly induced by the enhanced cathode jet.
文摘PSPICE model driven by an electric equivalent circuit of a piezoelectric circuit is presented. In order to confirm this model to be effective, an independent model of cold cathode fluorescent lamp(CCFL) driving circuit is used to conduct simulations, leading to a precise modeling. A library is configured through modeling and its accuracy is verified through simulations for widely used and representative lamps such as CCFL, fluorescent lamps, HID lamps, and electrodeless fluorescent lamps. On the basis of experiments, a lamp simulation is also performed using PSPICE, which allows us to take advantage of the lamp library easily. Also, PSPICE model driven by an electric equivalent circuit of a piezoelectric transformer is presented. In order to confirm this model to be effective, an independent model of CCFL driving circuit is used to conduct simulations, leading to a precise modeling. In addition, a new type of electronic ballast is proposed, which allows 35 W-class(T5-class) fluorescent lamp to work. This system is built by a rectifier which has improved power factor and half-bridge series resonant inverter. Also, with size of 27.5 mm high, 27.5 mm wide and 2.5 mm thick, the produced piezoelectric transformer has a high step-up ratio, through which it is possible for the electric ballast circuit to be lighter, smaller and more efficient. After the produced ballast is used to drive the fluorescent lamp for 25 min, it yields 0.95 in power factor correction, 86% in efficiency, 35.07 W in output voltage and 20.5 °C in temperature increase while meeting the characteristics of the 35 W-class fluorescent lamp.
基金supported by the National Natural Science Foundation of China(No.91436210)
文摘The intensities of fluorescence spectral lines of Ca atoms and Sr atoms in two different hollow cathode lamps （HCLs） are measured by element-balance-detection technology. In the wavelength range of 350–750 nm in the visible spectral region, using the individual strongest line （Ca 422.67 nm, Sr 460.73 nm） as the bench mark, the population ratios between the excited states of Ca atoms and Sr atoms are calculated by rate equations and the spontaneous transition probabilities. The HCLs with populations at excited states can be used to realize the frequency stabilization reference of the laser frequency standard.
