Analytical laser ablation of solid samples for ICP, ICP-MS, and FAG-MS analysis

摘要

This invention is improved laser ablation of solid samples analyzed by inductively coupled plasma (ICP), ICP mass spectrometry, or flowing afterglow mass spectrometry. A mirror-with-hole eliminates chromatic aberration in sample viewing and allows rad-hardening for radiation hot cell analysis of nuclear waste. Other attributes facilitate comprehensively rad-hardened laser ablation. Additional improvements include large, homogeneous laser spots, long-focus objective lenses, variable laser path length with built-in re-alignment, variable demagnification ratio, higher powered SMR lasers with larger spots enabling sensitive bulk solids analysis, demountable gravitationally self sealing stack assembly sample ablation cells, and laser ablation sample changers.

主权项

1. A target viewing system for laser ablation in which applications of the target viewing system are selected from the group consisting of laser ablation analysis of solid target samples, rad-hardened laser ablation analysis of high-activity radioactive solid target samples in a radiation hot-cell, rad-hardened laser ablation analysis of low-activity radioactive solid target samples in a radiation hot-cell, and laser micro-machining of solid target materials, and in which a target illuminator illuminates an area of interest on the target independently of the laser beam which independently ablates the target within its illuminated area of interest, and in which illumination light rays reflected from the illuminated target and viewed by the target viewing system are essentially coaxial with a final segment of the laser ablation beam immediately preceding the target, but in which the target view is not taken through any laser focusing optic, and in which the laser focus is thereby optically decoupled from the target viewing system focus, and in which the target is selected from the group consisting of a solid target sample to be analyzed by laser ablation, a high-activity radioactive solid target sample to be analyzed by rad-hardened laser ablation in a radiation hot-cell, a low-activity radioactive solid target sample to be analyzed by rad-hardened laser ablation in a radiation hot cell, and a solid target material to be micro-machined, and in which the laser ablation beam passes through an opening in an angled target viewing mirror in which the opening is selected from the group consisting of a round hole, an elliptical hole, and a slot, and in which the illumination light rays initially reflected from the illuminated target comprise the primary target view rays, and in which the target view rays are secondarily reflected toward a viewing system selected from among the group consisting of a viewing camera, a viewing projector, and a viewing eyepiece, and in which the secondary reflection of the target view rays occurs from an area of the angled target viewing mirror selected from the group of areas consisting of an area which is essentially concentric to the perimeter of the opening, an area which essentially surrounds the perimeter of the opening.