Optimal ray-tracing schemes in the mid-IR range through the main model shapes of rough and polished diamonds

An analysis of ray-tracing schemes in the mid-IR range through the main model forms of rough and polished diamonds used for determining content of basic defects based on optical absorption measurements has been carried out. It is shown that in the traditional transmission measurement scheme only a small fraction of the radiation incident on the crystal is detected due to refraction and scattering in many crystals, leading to decreasing of the signal-to-noise ratio and to narrowing of the signal levels dynamic range. Practical recommendations are given and optimal variants of ray-tracing schemes through the most characteristic crystal shapes are proposed. This makes it possible to detect the maximum fraction of the radiation transmitted through the crystal, and to implement effective measurements of optical absorption in a wide dynamic range to determine the concentrations of basic defects with a high signal-to-noise ratio.