摘要 |
<p>A reflecting optical dosimeter is described in which there is provided a thin block of optical material. The block has at least a first pair of parallel edges and preferably a second pair perpendicular thereto, and includes an input light pipe at a small angle from the perpendicular to one edge of said pair. Output light path means are also provided, so that light entering via the input pipe is reflected several times between at least said pair of edges, before exiting via the output light path means. The optical material of the block becomes darker in response to given radiation, so that the decreased transmission of light along the path from the input pipe to the output light path means is a measure of the dose of said given radiation. More preferably, one corner of said block is cut at substantially 45.degree. to form a small fifth edge. All five edges are coated to be reflective except at said light pipes. Light is reflected from the fifth edge and then back and forth between the second pair of edges before exiting. Most preferably the optical material is a halide crystal, and the block is one unit thick, N units between the edges of said pair and M plus one half units between the edges of the second pair, while the fifth edge is the square root of two units in length, with the output light pipe being at least one and one half units long.</p> |