Home – Home – Jornals – Avtometriya 2003 number 5

Triangulation optical methods for melt level measurement in a crucible during crystal growth are analyzed. Main attention is given to the active method using a laser triangulation sensor. Estimates of the metrological characteristics (systematic measurement errors and effective range) depending on the level of melt, its angular velocity, the distance from the measurement zone to the center of rotation, and the crucible coordinate are presented. The limit value of the melt rotation speed is also estimated. The requirements to the optical system providing the maximal measurement range and also to the algorithms of processing of the optical signal formed as the sensor beam is reflected from the nonstationary mirror surface are formulated. The features of melt level measurement using a passive binocular sensor are discussed.