| Application: Agricultural Food Product Sorting and Inspection Systems |
Moisture is a key indicator of process control and quality in agriculture, textile processing, and the forest-product industry. Because water is opaque to SWIR illumination, detecting its presence or absence can be useful in gauging crop health and product ripeness or dryness.
Gauging the relative moisture content of leaves helps assess crop health and quality. By selectively imaging at the wavelengths of strongest absorbance for water, items with higher water composition will appear darker than drier tissues.
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| Viewing the corn in visible (left image) and in SWIR wavelengths around 1475 nm (right image) identifies the two ears on the right as fresher than the three on the left (they were purchased on same day versus the week before). The tip of the ear stem in the lower right of the image is bright white at this wavelength as dries out when the ear is ripe. |
The bottom portion of the ear on the right is much darker in the area that the visible image shows damage, indicating a pooling of moisture characteristic of bruising. Such bruises can be seen under the skin of fruits that are passing by on an inspection line while they are invisible to the eye. Though perfectly suitable for many processed foods, bruises are not acceptable in fresh produce for retail purchase. The SWIR camera permits sorting high value produce away from the lower grade fruit prior to processing.
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| Viewing the apple in visible (left) and in SWIR (right) wavelengths demonstrates that bruises can be seen in the short wave infrared and are not apparent in the visible. | |
In textile processing, moisture detecting SWIR imagers are useful in the dyeing process. In particleboard manufacturing, online SWIR-based machine vision systems measure moisture in chips, and the collected data is used to regulate heating and drying operations downstream.
Contact Goodrich to see how SWIR Imaging can meet your needs!