NIR Moisture Measurement with Selectively Radiating Sources

摘要

Moisture measurement in continuously running processes often requires on-line methods. The NIR principle (Near Infrared Reflection) which is based on the absorption of infrared radiation has proven useful especially for non-contact applications and moving granular materials. This paper presents a new method using a number of different IR-LED as selectively radiating sources. They are chopped electronically. Therefore, the device has no moving parts and is compact. The influence of several variables on NIR moisture detection will be discussed.