Subject(s)
Abscess/complications , Amenorrhea/etiology , Tuberculosis, Female Genital/complications , Tuberculosis, Pulmonary/complications , Abscess/diagnosis , Adult , Female , Humans , Pelvis , Tuberculosis, Female Genital/diagnosis , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/drug therapyABSTRACT
High conversion efficiency over a wide microwave band has been achieved in a high-power CdTe single-sideband electro-optic modulator working at 10.6 microm by dividing the modulator into two sections and driving each separately.
ABSTRACT
The output and transmission characteristics of both single and double (tandem) integrating spheres have been studied with a lead-salt diode laser in the 2000-cm(-1) spectral region. For an f/20 input beam, the effective length is about eight times the diameter of the sphere. The corresponding transmittance is ~10(-5) for the tandem spheres. The output beam has a Gaussian profile.
ABSTRACT
A diode-laser dual-beam spectrometer using reflective optics and a special lock-in amplifier has a 100 +/- 0.25% base line flatness and a long-term base line drift of <0.25%. The system is highly immune to fringe interference occurring before the ratioing system.
ABSTRACT
The low-frequency noise characteristics of several stripe-geometry Pb-salt semiconductor diode lasers were investigated in the 4-11-microm spectral region. Excess noise is observed to vary as the ratio of I/I(t), where I is the injection current and I(t) is the threshold value at which lasing action begins. The magnitude of the diode laser excess noise has been measured to be 24 dB above shot noise at threshold.
ABSTRACT
A tunable diode laser has been incorporated as a source in an operating high resolution vacuum grating spectrometer. The advantages of such a system for recording molecular spectra have been elaborated. In the process of developing this system, several practical problems came about, and it has been considered useful to document the manner in which they have been resolved. In particular, for work in the region of 15 microm, it was advantageous to develop an air-spaced Fabry-Perot etalon to record fringes simultaneously with the scanning of molecular spectra. This was successfully done, and the upsilon(2) band lines of the HCN molecule at 14 microm have proved to be ideally suited for determining the fringe spacing spectroscopically.
ABSTRACT
The detection sensitivity of a long-path atmospheric pollutant monitor using tunable diode lasers has been greatly improved to about 0.1%. These improvements directly result from measurements made on the low frequency noise characteristics of several diode lasers and the temporal spectrum of atmospheric turbulence. Optimum modulation frequencies are given, and an improved optical design is recommended.
ABSTRACT
Using a tunable diode laser spectrometer with a spectral resolution of about 10(-4) cm(-1), the important central portions of the two ir absorption bands of H(2)SO(4) at 8.2 microm (1222 cm(-1)) and 11.3 microm (880 cm(-1)) have been scanned at low pressure (0.67 Torr of H(2)SO(4)) and atmospheric pressure (H(2)SO(4) with ~1 atm N(2)). Maximum absorption coefficients have been measured to be 6.5 cm(-1)-atm(-1) and 6.9 cm(-1)-atm(-1) at the 8.2-microm and 11.3-microm bands, respectively. A novel spectroscopic method was used to determine the temperature dependence of the dissociation of H(2)SO(4) into SO(3) and H(2)O in the 127-220 degrees C range.
ABSTRACT
The anomalies that crystalline plates introduce in the quality of an image have been known for many years. With its ability to control the polarization of its output, the laser makes reexamination of these anomalies practical. Using a birefringent lens, we have produced spatially separated multiple images. Dual focal points were achieved through polarization control by utilizing the ordinary and extraordinary beams in a thin crystalline lens. Further considerations indicate the possibility of achieving F = 2(n) focal points through electrooptic control, where n is the number of thin, birefringent lenses.
