Optical sensor for determining dry matter content of e.g. product, has LEDs distributed in circle to ensure homogeneous illumination of product, and photodetector for receiving spectrum backscattered directly by product

摘要

The sensor has a set of LEDs (2) for illuminating a product, and an electronic circuit for processing a spectrum backscattered by the product, where the LEDs are distributed in a circle to ensure homogeneous illumination of the product. A photodetector (3) is placed at a center of the circle to receive the spectrum backscattered directly by the product. The LEDs emit the same frequency modulated signal in a near infrared with a defined carrier frequency and a defined modulation frequency. An independent claim is also included for a method for determining dry matter content of a product by an optical sensor.