To improve product quality and streamline processes, manufacturers seek more effective methods of in-line color monitoring. In this application note, Ocean Insight discusses a versatile spectral system for non-contact color measurements.
Color is one of the first things we notice about an object. In industry, color is often considered an important element of quality. This compels manufacturers to seek the most effective methods to measure color quantitatively, to meet demanding design specifications.
Overall aesthetics are important, too, especially when products are assembled from multiple parts or viewed next to others on a shelf or under different lighting conditions. This can translate into perceived quality differences that give one manufacturer an edge versus its competitors. Beyond aesthetics, color is an important characteristic in applications as diverse as evaluating chemical reactions, ensuring food is safe to eat, and producing consistent safety signage and indicators.
Color Measurement
Measuring color is challenging, as the way we detect color is not directly related to easily quantified parameters such as light intensity. Accurate color measurement is significantly more complex than simply taking the red, green and blue channels from a color camera. Color is dependent on the sample, on calibrating the setup for the illuminant and detector being used, and on subjective human perception. Also, measurement geometry is critical for compliance with international standards and to ensure consistency across sites. Each of these elements involves many subtleties that are critical in producing accurate, repeatable results.
Spectroscopy is an excellent method for measuring the nuances of color. For example, unlike a single-wavelength device, a spectrophotometer captures the full color spectrum at very high resolution, allowing for careful, detailed analysis of data. This provides a degree of flexibility not available using other color measurement methods.