Measuring inclusion depth

The measurement herein determines the depth of an inclusion in a solid media such as fused silica. A trigonometric function such as the tangent calculates the depth of the inclusion. A light source having a primary incident beam of light enters a solid media having at least one inclusion therein. The primary incident beam of light enters the solid media on a straight line path at an angle to a horizontal axis and secondary scattered light is detected at an angle to the horizontal axis. Preferably, the detector is positioned on a perpendicular axis above the inclusion and the angle of the primary beam to the horizontal axis is 45 degrees. The solid media has an exterior surface parallel to the horizontal axis and the primary beam of light and the perpendicular axis intersect the exterior surface. As a result, the perpendicular axis intersect is equidistant from the primary beam intersect and the inclusion. The scattered light can be viewed from many directions with varying intensities.