ABSTRACT
A tunable, lamp-pumped Cr3+:LiCaAlF6 laser that operates in the 760-800-nm wavelength range is demonstrated. As a passive Q switch the V3+:YAG crystal, characterized by wide saturable absorption in the 760-900-nm wavelength range, was applied. The V3+:YAG parameters were determined by spectroscopic and saturable transmission measurements. The 30-mJ output energy at 2-Hz repetition rate in the free-running regime was obtained in a cavity reinforced by a diaphragm near the fundamental mode. The dispersive prism inserted into the cavity enabled tuning in the 760-800-nm wavelength range. In the passive Q-switching regime we achieved greater than 1-mJ energy with 50-ns pulse duration in a 35-cm-long cavity. A numerical model that takes into account the short recovery time of V3+:YAG (approximately 5 ns) and excited-state absorption was used to analyze such a laser.
ABSTRACT
The paper presents the problems related to safe use of lasers being the parts of medical devices. There were discussed laser radiation interaction on biological tissues, hazards that arise during the work with laser devices, as well as fundamental safety rules and obligatory radiation protection standards. The selected constructions of anti-laser filters used for eyesight protection were also presented.
Subject(s)
Equipment Safety , Laser Therapy , Lasers/standards , Radiation Protection/standards , Humans , Radioactive Hazard Release/prevention & controlABSTRACT
Examples of in vivo detection of skin neoplasmas (Mercl, melanoma) and breast carcinoma using laser induced fluorescence (LIF) and bis-1[1-alanylo-N]-ethylodeuteroporphyrin (Ala-PP) are described in this study. Photosensitizer, wave titanium laser and standard CCD camera coupled to vision amplifier enable precise neoplasm imaging, Ala-PP retention monitoring and further photodynamic therapy (PDT).
