A versatile instrument for thermal expansion and contraction measurements, DIL 806 uses an innovative measurement principle to make unconventional experiments possible, and to improve many conventional tests . 
 
This optical dilatometric measurement method used in DIL 806 is an absolute process, entirely independent of any possible expansion or contraction of the instrument. Consequently, measured results do not need to be corrected or calibrated for different temperature programs. Coupled with the fast response of the DIL806 furnace, this makes the system particular well-suited for the analysis of dynamic processes that involve multiple temperature steps and dynamic heating rates. 
 
A high-performance LED emits a broad-width planar light beam onto the sample. The sample shadow is detected by a high-resolution CCD sensor. The signal is then evaluated by a digital edge-detection processor which provides a sensitive and precise measurement of dimensional change. This principle is known as the shadowed light method and provides an accurate and absolute measurement of the sample dimension with changing temperature. 
 
The sample, positioned on a platform in the center of the disc-shaped furnace, is not subjected to external forces. Hence DIL 806 is a dilatometer particluarly suited for the measurement of metals and, with the optional sub-zero furnace, plastic samples. 
 
Thin samples are also easily analyzed with the sample holder specifically designed for this purpose. 
 
The broad width of the incident light means that sample preparation is not as demanding as in other classic dilatometric techniques, and the sample does not need to have be positioned precisely on the platform, improving usability also for unexpereinced operators. 
 
The initial length is automatically determined and saved for the subsequent calculation of the linear thermal expansion coefficient. 
 
The furnace is capable of rapid heating speeds up to 100 °C/min and cooling times from 1400 °C to 50 °C in under 10 minutes.