Ruby laser

About: Ruby laser is a research topic. Over the lifetime, 2474 publications have been published within this topic receiving 38933 citations. The topic is also known as: corundum laser & ruby rod.

Selective Photochemistry of Bromine Using a Ruby Laser

Abstract: Gas‐phase photochemical addition of bromine to olefin molecules has been studied by inducing the reaction with monochromatic light near 6940 A from a pulsed, tunable ruby laser. All previous photochemical reactions of bromine were induced with light at wavelengths shorter than 6800 A, and were found to proceed by means of free radical chains. The Br atoms initiating these chains are produced by direct dissociation of Br2 molecules upon absorption of light in the continuum. The present investigation shows that free‐radical chains are responsible for the reaction at 6940 A, also. However, direct dissociation at this wavelength is found to be negligible, and the Br2 molecules are excited to individual bound levels 500 to 800 800 cm− 1 below the dissociation energy. Kinetic and isotopic evidence shows that the additional energy is furnished by subsequent collisions, so that about 1% of the excited Br2 molecules become dissociated and can initiate the reaction. The remaining excited Br2 molecules relax by collisions to the ground state at a rate somewhat higher than the gas–kinetic‐collision rate.

Comparing the effectiveness of Q-switched Ruby laser treatment with that of Q-switched Nd:YAG laser for oculodermal melanosis (Nevus of Ota)

Abstract: Summary Background and objective The objective of this study was to compare the efficacy and safety of Q-switched Ruby laser versus Q-switched neodymium:yttrium–aluminium–garnet (Nd:YAG) laser for oculodermal melanosis (Nevus of Ota) birthmarks in a large group of patients. Study design/Materials and methods A retrospective review was conducted of 94 patients with Nevus of Ota treated with a Q-switched Ruby laser and a Q-switched Nd:YAG laser over a 3-year period. The subjects' ages ranged from 3 to 64 years; there were 70 females and 24 males, all of whom were of Asian descent. The number of treatments ranged from 1 to 8. Duration of treatment ranged from 6 months to 3 years and 10 months, with a mean of 14 months. Patients ( n =47) received Q-switched Ruby laser treatment (694nm) using light dosages of 7–10Jcm −2 . Subsequent patients ( n =47) received Q-switched Nd:YAG laser treatment (1064nm) using light dosages of 7–10Jcm −2 . The primary efficacy measurement was the quantitative assessment of clearing and fading response using the DermaSpectrometer for the Q-switched Ruby laser group versus the Q-switched Nd:YAG laser group. Results Based on a paired t- test, clinical and statistically significant differences in clearing and fading response were observed amongst the Q-switched Ruby laser-treated subjects as preferred to the appearance of Q-switched Nd:YAG laser-treated group ( P Conclusion Use of a Q-switched Ruby laser resulted in better clearing and fading as compared with Q-switched Nd:YAG laser.

Versatile high-power single-longitudinal-mode pulsed dye laser

Abstract: A versatile high-spectral-energy density dye laser suitable for lidar applications and high-resolution spectroscopy is reported. The dye laser includes an oscillator and preamplifier and two amplifier stages. With transverse pumping by the second harmonic of a Nd:YAG laser, an efficiency of 55% was achieved at 589 nm, providing 165 mJ in a single-longitudinal mode. Second harmonic generation results in a dye laser-to-UV conversion efficiency of 33%. Optimization of dye solutions covering the 565–880-nm range is presented. The laser was also pumped with a ruby laser, producing an output energy of 400 mJ at 770 nm.

An experimental study of the diagnostic potential of laser selective excitation spectroscopy for a potassium plasma

Abstract: A thermally tuned Q -switched ruby laser of moderate power, with emission wavelength at 6939 A, has been used to selectively excite the 4^{2}P_{3/2}-6^{2}S_{1/2} transition in the atoms of a pure potassium plasma of low degree of ionization produced in a hot cathode diode. A pulse of intensified spontaneous emission has been observed at 6939 A, 6911 A, and at a number of other wavelengths. The possibility of using this type of interaction for localized plasma diagnostics has been studied experimentally. It has been found that the intensified signal decay time decreases with increasing electron density, thereby providing a potential means for measurement of this parameter. In particular, it is shown that because of a saturation effect, the recorded signal characteristics depend to some extent on the laser parameters. A specially tailored laser performance is suggested as essential in order to overcome these problems and obtain signals which depend unambiguously on the plasma conditions.