What’s the color of this thing?

When color is a critical part of the process control, it makes sense to avoid human operator detection and rely on a sensor and computing systems to perform the measurement. While the growth will be in the single digits, a recent report projects that the global color detection sensor market will reach $3.01 billion by 2021.

The report segments the color detection sensors market by types into color sensing, RGB sensing, luminescence sensors, brightness sensors, contrast sensors and print mark sensors.

Color sensors use three methods and two color sensing schemes. The photoelectric sensors use light to digital (LTD), light to voltage (LTV) and light to frequency (LTF) conversion methods to sense light and color. The two basic color sensing systems are reflective and transmissive. Reflective sensing detects the color of light reflected from a surface. In contrast, transmissive sensing detects the color of light from a light source.

Technology for color sensors include white LED and filtered detectors, and variations that include multiple LEDs, white light illumination with reflected color measurements, patented pulsed LED technology, fiberoptics and more. The texture of the object and transparency can provide challenges to typical color detection systems and are driving forces for some advanced color detection schemes. The detection of subtle color difference can also increase the sensing difficulty

Industries that rely on color sensors include consumer electronics, food & beverage, packaging, manufacturing and automotive. In addition to automation technology, color sensors are also used in medical packaging, quality control, as well as in painting, surface-labelling and printing.