Beyond the conventional red, green, and blue (RGB) color spectrum captured by normal cameras, a world of hidden information lies waiting to be unveiled. Multispectral Imaging (MSI) is a powerful technology that allows us to visualize this unseen world and reveal useful information. The data extracted can be used to revolutionize diverse fields ranging across precise color matching in industrial applications, in-depth analysis for cosmetics and skin care, agricultural growth and health monitoring, and even advanced diagnostics in medical settings. The technology has existed for many years, but only recently has it become available for a broad audience through affordable snapshot multispectral image sensors.

In this article, we’ll explain what multispectral imaging is, how it works, and its key applications, along with an introduction to how companies develop compact, high-performance snapshot multispectral imaging solutions.

 

What is Multispectral Imaging?

Multispectral Imaging (MSI) is a technique that captures and analyzes images across multiple, specific wavelength ranges of the electromagnetic spectrum. As seen in Figure 1, compared to many off-the-shelf RGB cameras that only capture red, green, and blue wavelengths, multispectral imaging captures many spectral datapoints for each pixel in an image.

To give a real-world analogy, it’s like seeing through a set of colored sunglasses, each tuned to reveal hidden details. For example, Spectricity’s S1 Multispectral Image Sensor supports operation in 15 independent color channels, covering 400 nm to 700 nm. The richer data allows detailed analysis, identification, and advanced AI algorithm development that could not be achieved with an ordinary RGB camera.

 

How Multispectral Imaging Works: Technology Explained

Achieving Snapshot Multispectral Imaging

Understanding what multispectral imaging is only tells half the story. It’s also essential to delve into the technology behind, and how it evolved —from slow, mechanical systems to fast, compact snapshot solutions.

Traditional methods rely on sequentially modifying incoming light and capturing multiple images to create a composite multispectral image. For example, filter wheel imaging rotates a wheel of narrowband filters, capturing separate images for each filter. Similarly, prisms or gratings split light into multiple wavelengths, requiring mechanical scanning to assemble a full spectral image. These techniques are slow, rely on costly photonic components, and require bulky mechanical assemblies—making them impractical for mobile or handheld applications. Their high cost has also limited adoption for consumer-oriented use cases.

To make multispectral imaging accessible to broader markets, snapshot multispectral imaging is essential. Currently, only two key technologies exist to achieve spectral separation while capturing live images in a tiny format at a low price point: organic color filters and interference filters. Both approaches build on standard CMOS image sensors and apply static optical filters directly at the pixel level. This design trades some spatial resolution for spectral resolution while preserving the speed, cost-effectiveness, and compact form factor of modern camera technology—bringing multispectral imaging to everyday devices.

Organic Color Filters

Organic color filters rely on specially designed dye materials that selectively absorb certain wavelengths, while allowing others to pass through. The absorption spectra can be engineered by chemical synthesis to achieve custom spectral bands needed in multispectral imaging. This kind of filters can be deposited onto sensor surfaces relatively easily, making them cost-effective for some imaging applications.

However, the spectral filter responses of organic color filters are very broad (>100 nm), which requires extensive data processing to extract detailed spectral information, limiting the application for multispectral imaging. Furthermore, consistency and long-term stability remain a challenge, as the organic compounds tend to deteriorate over time. As a result, while organic filters are suitable for basic color separation, they fall short when it comes to advanced multispectral imaging applications.

Interference Filters

Interference filters, such as those based on Fabry–Pérot interferometry, achieve spectral separation through precisely engineered layered structures. By controlling the thickness of these layers, specific wavelength bands can be selectively transmitted while others are blocked.

This approach delivers superior spectral resolution, stability, and higher performance for spectral reconstruction, compared to dye-based filters. It also enables compact and chip-scale integration, making it ideal for high-performance multispectral image sensors for mass production in mobile and consumer electronics.

Spectricity’s FP Precision Filter Technology

Spectricity’s Multispectral Image Sensor integrates unique and patented FP Precision Filter Technology in a mosaic pattern on a CMOS image sensor. In Figure 2, Spectricity controls the filter center wavelengths by differentiating the thickness of the layers built on a CMOS image sensor. As a result, each pixel yields a narrowband response. The FP Precision Filter Technology is scalable and adaptable to any image sensor, bringing multispectral imaging to tiny form factors.

 

Key Applications of Multispectral Imaging

Multispectral imaging (MSI) transcends the limitations of traditional photography by capturing information beyond an RGB camera. This powerful technology has found its niche in a diverse array of fields to unlock hidden information, enabling more informed decisions and deeper understanding across countless applications.

• Color Matching: Accurate color picking with mobile sensing and advanced color correction for AWB
• Food & Agriculture: Monitoring of plant growth and health, food freshness & quality inspection, species sorting
• Medical: Monitoring of wound healing, prevention of diabetic foot ulcers, and skin cancer
• Security and Surveillance: Detecting concealed objects, identifying counterfeit documents, and CCTV monitoring
• Beauty & Health: Accurate skin tone detection, advanced skin analysis with biomarkers, and personalized skin care recommendations

Figure 3 illustrates this application in a skin care scenario. By leveraging Spectricity’s multispectral imaging together with advanced AI algorithms, users receive personalized skin care recommendations, such as skin tone and full biomarker maps, including melanin, blood volume, and skin oxygenation. This makes it easy for users to find their cosmetic match and diagnose skin issues like dark circles under the eyes.

 

Developing Compact Multispectral Imaging for Mobile Devices

As the potential of mobile multispectral imaging becomes increasingly clear, companies like Spectricity are at the forefront of bringing this technology to everyday devices. Spectricity specializes in developing miniaturized multispectral imaging solutions specifically designed for integration into mobile devices. Spectricity offers the following products, shown in Figure 4.

• S1 Multispectral Image Sensor: World’s first truly miniaturized, mass-manufacturable mobile multispectral image sensor featuring 15-channel high spectral resolution across 400 nm to 700 nm.
• S1-M Camera Module: A compact camera module that includes a specially designed lens and onboard memory for accurate and fully calibrated spectral responses of the S1 sensor.
• S1-EVK2b Evaluation Kit: A dual-camera unit consisting of a co-packaged S1-M multispectral camera module and RGB image sensor together with NVIDIA Jetson computer for application development.
• S1-A Accessory Device: A portable device equipped with the S1-M camera module that pairs seamlessly with mobile devices by connecting via a simple USB interface.

 

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Conclusion: MSI Sensing Beyond What Is Visible

To summarize, multispectral imaging (MSI) moves beyond standard RGB, revealing hidden data by capturing light across specific wavelengths. With the advent of snapshot multispectral imaging, this powerful technology has moved from bulky, expensive systems to compact, cost-effective solutions that fit into mobile devices.

This technology, like Spectricity’s miniaturized solutions, integrates unique filter tech onto sensors, providing richer insights for diverse applications. From precise color matching and enhanced security to advanced medical diagnostics and personalized beauty solutions, multispectral imaging is revolutionizing various fields. As mobile multispectral imaging becomes more accessible, it is set to transform everyday devices and empower smarter decisions across a wide spectrum of uses.

 

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More Resources

• Spectricity Demonstrates AI-Powered Skin Analysis with Multispectral Technology on Mobile Devices
• Spectricity Unveils S1-A Accessory Device for Plug-n-Play Spectral Imaging on Mobile Platforms

 

Discover how Spectricity’s multispectral imaging solutions can transform your next-generation device. Learn more about our products or contact [email protected] for a demo. Follow Spectricity’s LinkedIn and WeChat (scan QR Code: spectricitychina) accounts for more information.