‧A new approach to measuring surface colour based on digital imaging
‧Assesses the whole image or multiple regions of interest
‧Unaffected by surface texture
‧Generates a QC pass-fail assessment　

A New Approach to Surface and Appearance Measurement

The Lovibond CAM-System 500 exploits a new approach to quantifying surface colour and visual appearance, which replicates human perception of products. It employs digital image processing techniques for relative measurement of products versus approved samples. The hardware components include a digital colour camera, image capture cabinet with keyboard, controlled sample illumination and an embedded PC, all designed to function within an industrial QC environment.

Overall visual appearance is a major feature in the assessment of product quality. The Lovibond CAM-System 500 provides relative, quantitative measurement data, which allows the user to quickly decide whether a product meets acceptable colour and appearance criteria or if it has undesirable defects. It is particularly well suited to measuring natural products with non uniform colour as it includes colour distribution within a sample and measurements are not affected by surface texture. Furthermore the CAM-System 500 can either be used to assess the whole image or to perform simultaneous measurement of multiple regions of interest or colours. Typical applications include monitoring the browning of baked goods, quality assessment of fresh produce, measurement of fabric staining and QA of pharmaceutical tablets. The measurement area is also flexible, from small up to 100 mm. For more advanced image processing applications, the system has the potential for dimension and shape measurement in addition to colour and appearance analysis.

The CAM-System 500 includes separate supervisor and operator access. The supervisor has access to a set-up menu where they can establish the regions of interest and thresholds for sample analysis. All the operator has to do is call up the product settings and measure the sample to generate a pass-fail assessment without knowledge of colour science.

The Lovibond CAM-System 500 uses actual sample threshold limits for acceptance and rejection of the product. It can process the whole image or regions of interest (up to 32 per product type). It employs ‘blob extraction’ to isolate so-called blobs from images, allowing the user to exclude backgrounds or highlight those particular product areas of interest. A time profile screen allows the user to capture a sequence of images at set intervals and to display the results in a line chart.

A reports screen displays the set of previous tests in tabular format. The results may be sorted in product type, test or order

Camera Colour SVHS camera with 8 bit per channel colour depth, 752 * 582 pixel resolution.

Lighting White LED cluster with beam splitter for the camera view

Computer System Industrial embedded PC

Keyboard/Mouse PS2

Sample size Up to 100 mm diameter