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We conducted an earth-satellite laser long-path absorption experiment using the Retroreflector in Space on the advanced earth observing satellite, which was launched on August 17, 1996 by the National Space Development Agency of Japan. Two single-longitudinal-mode transverse, electric, atmospheric (TEA) CO2 lasers were used in the spectroscopic measurement of atmospheric trace species. One TEA laser was used to measure the absorption of the ozone, and the other to record a reference signal. We measured the absorption spectrum of the atmosphere using the Doppler shift of reflected beam caused by the satellite's movement. The ozone spectrum was successfully measured using the 10R(24) line of 13CO2 and the 9P(24) line of 12CO2. We studied the measurement error and reduced it by adding a spatial filter to the transmitter optics.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper reports the optical characteristics of the Retroreflector in Space (RIS) on the advanced earth observing satellite (ADEOS) in orbit. The RIS is a 0.5 m diameter single-element hollow cube-corner retroreflector with a unique design which uses a curved mirror to correct the velocity aberration caused by the satellite movement. We used a Nd:YAG laser to test the efficiency of the reflection at 532 nm. The ADEOS was actively tracked with a 1.5 m diameter tracking telescope using the image of the RIS lit by the Nd:YAG laser. We measured the intensity of return light with an image-intensified CCD camera on the guiding telescope with a diameter of 20 cm. The intensity of the return was quantified by comparing it with images of stars. We compared the result with the theoretical reflectance of the RIS, and confirmed that the reflectance of the RIS agreed with the designed value. The return from the RIS was comparable to a stellar magnitude of 2 to 3, depending on the elevation angle when lit by a 0.3 W laser with a beam divergence of 0.5 mrad.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We have evaluated the angioscopic findings before and after various percutaneous techniques to treat 39 lesions in 32 cases of arteriosclerosis obliterans (ASO). We applied a laser (CL50: SLT, Japan), percutaneous transluminal angioplasty (PTA), and atherectomy -- either singly or in combination, with angioscopic luminal observation (angioscope: PF14L & PF18L Olympus, Japan) recorded before and after the treatments. In the case of a complete obstruction, we employed PTA as the first choice. We used a laser prior to PTA when the PTA guide-wire failed to penetrate the lumen. For eccentric and calcified lesions atherectomy was applied. A sufficient enlargement was obtained initially in 37 of the 39 lesions. The angioscopic observations after treatment revealed carbonization (3/5) and attachment of small thrombi (3/5) after using the laser, intimal rupture (3/8), dissection (2/8), flap formation (2/8), and attachment of small thrombi (4/8) after PTA, and attachment of small thrombi (9/19), flap formation (6/19), and dissection (2/19) after atherectomy. We established the efficacy of angioscopic assessment demonstrating beneficial clinical results. The angioscopic findings suggest that attachment of small thrombi may be responsible for a poor prognosis. Additional angioscopic observations with angiography are recommended for improved understanding of the luminal changes.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.