AMS AS7341 11-Channel Multi-Spectral Digital Sensor

An interesting sensor module came to my attention recently thanks to the experiments of my talented friend Emily Velasco. She’s been building a contraption whose sound output is dependent on color. At first, the sensor module didn’t capture my attention because I’ve seen color sensors before. They’ve been available for fun projects like a M&M candy sorter, and many robotics/electronics kits like LEGO Mindstorms included their own. However, not all color sensors are equal. Once I looked into the AMS AS7341 sensor she was using, I learned it was far more capable than I had originally thought.

Instead of mapping color hue into a single reading, which is what I had expected, this sensor reports data across eleven channels. Eight of the channels are mapped to various wavelengths in the human visible spectrum, implemented via filters placed over optical sensors. The remaining three channels report color-independent data. One channel has no color-specific filter (“clear”) and would report an overall brightness value. One channel is sensitive to near infrared (NIR), outside visible spectrum. And the final channel is specialized for detecting common flicker frequencies 50Hz and 60Hz.

AMS product page for this sensor stated intended use cases for this sensor included color calibration tools. This sensor is intended to be a fundamental part of precision color instruments! All color sensors answer the “What color is it” question to varying degrees of precision. This sensor is aimed at the highly precise end of that spectrum. Note that the sensor by itself is not a color calibration tool, that will depend on the rest of the supporting electronics, software, and procedures for use. “How to calibrate the calibration tool” is a big field all by itself and critical for instrument accuracy in addition to precision.

I have very little background in color science, so I will start by looking at the sensor as a precision instrument of unknown accuracy. Even with that disclaimer I think it is a good project candidate.

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