Multi-channel spectral sensor for mobile colour measurement

The new sensor’s small dimensions also mean that it is easier to accommodate it in mobile phones and other portable devices.

“The AS7341 marks a breakthrough in the category of spectral sensors in a small package suitable for mounting in a mobile phone or consumer device. It is the smallest such device to offer 11 measurement channels, and also offers higher light sensitivity than any other multi-channel spectral sensor aimed at the consumer market,” said Kevin Jensen, Senior Marketing Manager in the Optical Sensors business line at ams.

Consumer benefits of the AS7341 include improved performance in mobile phone cameras, as the chip’s accurate spectral measurements enable superior automatic white balancing, more reliable light source identification and integrated flicker detection. The technology will more accurately reproduce colours and minimise distortion of ambient light sources, resulting in sharper, clearer and more true-to-colour photographs. The AS7341 also will enable consumers to use their mobile devices to match the colours of objects such as fabrics through using colour references like the PANTONE Colour System.

The power of the AS7341 to upgrade colour measurement performance is demonstrated by the introduction of the Spectro 1 portable colorimeter from Variable. In the Spectro 1, Variable has used the AS7341 to provide professional colour measurement for solid colours at a consumer price point. The product provides highly repeatable spectral curve data in ten nanometre increments across the visible light spectrum from 400 to 700nm, a capability previously only available in professional spectrophotometers.

George Yu, CEO of Variable, added: “In our opinion, no other spectral sensor IC comes close to offering the multi-channel capability of the AS7341 from ams in such a compact chip package. This small size is a crucial benefit – integration with a mobile phone app is one of the key features of Spectro 1, and we have designed the product to be small enough to hold easily in one hand. And the multi-channel spectral measurements provided by the AS7341 mean that users of Spectro 1 will never be misled by false matching of metameric pairs.”

The AS7341 is a complete spectral sensing system housed in a tiny 3.1x2.0x1.0mm LGA package with aperture. It is an 11-channel device which provides extremely accurate and precise characterisations of the spectral content of a directly measured light source, or of a reflective surface. Eight of the channels cover eight equally spaced portions of the visible light spectrum. The device also features a near infrared channel, a clear channel, and a channel dedicated to the detection of typical ambient light flicker at a frequency of 50Hz up to 1kHz.

Beside camera image optimisation, the AS7341 spectral sensor also supports various applications, such general colour measurement of materials or fluids, skin tone measurement, and others.

The AS7341, will be demonstrated at CES 2019 (Las Vegas, NV, 8-11 January 2019), and is available for sampling. Mass production starting in February. Unit pricing is $2.00 in an order quantity of 10,000 units.