Laser induced fluorescence was used for measurement of concentration of hydroxyl (OH) radicals in the plasma pencil, which is a radiofrequency plasma jet operated in argon at atmospheric pressure. The problematic of the rotational energy transfer, spectral overlap of the laser line and hydroxyl absorption line and saturation effects were treated. The method was calibrated by Rayleigh scattering...

Argon laser burns of varying intensity (50 mW./0.2 sec/50 p, 100 mW./O.l sec/100 p, 100 mW./0.2 sec/200 p, and 100 mW./0.2 sec/400 p) were made in the region of the maculopapillar bundle of four human eyes 24 hours prior to enucleation for malignant melanoma of the choroid. Light and electron microscopic observations revealed that it is possible to produce chorioretinal lesions between the disc...

Laser frequency-modulated (FM) spectroscopy has been used as an axial probe of a laser-guided electric discharge in sodium-argon vapor contained in an optically accessible metal heat pipe oven. Absorption measurements in the region 23 106-23 881 cm-1 provided accurate line positions (&plusmn;<0.006 cm-1) for 141 transitions in the v' = 3-8 <-- v" = 0 and v' = 5-9 <-- v" = 1 bands of NaH (A1Sigm...

This paper deals with pure argon plasma studied in a magnetically enhanced inductively coupled reactor. Laser induced fluorescence technique was performed with an optical parametric oscillator laser on the 3d 4F7/2 and 3d 2G9/2 Ar + metastable levels and on the (2P3/2 0 )4s neutral metastable state to determine their relative densities. Langmuir probe was used as a complementary diagnostic to m...

This article presents a method used to guide the beam from an argon fluoride excimer laser to make it suitable for microsurgical purposes and confine it to areas that can be varied in dimension from 1 micron to tens or hundreds of microns. This approach guides the excimer laser beam with an articulated mechanical arm and confines it with variable-diameter tapered tubes, possibly allowing the us...

So far, nonsequential double ionization (NSDI) of atoms can be well understood within a semiclassical or even classical picture. No quantum effect appears to be required to explain the data observed. We theoretically study electron correlation resulting from NSDI of argon in a low-intensity laser field using a quantum-mechanical S-matrix theory. We show that quantum interference between the con...

We describe techniques for making sensitive and high-dynamic-range measurements of laser amplitude and envelope phase noise (timing jitter) in the frequency domain at the shot-noise limit. Examples of amplitude noise measurements on continuous-wave argon-ion and diode-pumped solid-state lasers used for pumping a femtosecond Ti : sapphire laser are presented. Amplitude and phase noise measuremen...