Emerging image sensor technologies explored in report
Image sensing is an essential capability, utilized across multiple applications that range from webcams and smartphone cameras to autonomous vehicles and industrial inspection. The IDTechEx report – Emerging Image Sensor Technologies 2021-2031: Applications and Markets – explores the market for emerging image sensors, covering a diverse range of sensor technologies that span from thin film flexible photodetectors to event-based vision.
While conventional CMOS detectors for visible light are well established and somewhat commoditized, at least for low-value applications, there is an extensive opportunity for more complex image sensing hardware that offer capabilities beyond simply acquiring red, green, and blue (RGB) intensity values at each pixel. This largely stems from the ever-increasing adoption of machine vision, in which image analysis is performed by computational algorithms. Machine learning requires as much input data as possible to establish correlations that can facilitate object identification and classification, so acquiring optical information over different wavelength ranges, or with spectral resolution, for example, is highly advantageous.
Further, emerging image sensor technologies offer many other benefits. This can include similar capabilities at a lower cost, increased dynamic range, improve temporal resolution, spatially variable sensitivity, global shutters at high resolution, reducing the unwanted influence of scattering, flexibility/conformality, and more.
The report covers many emerging technologies, specifically:
- Quantum dots on silicon hybrid image sensors;
- Organic photodetectors on silicon hybrid image sensors;
- Emerging SWIR image sensor technologies, including extended range silicon;
- Organic and perovskite photodiodes (OPDs and PPDs);
- Event-based vision;
- Hyperspectral imaging;
- Flexible x-ray image sensors;
- Wavefront imaging;
- Emerging Image Sensor Technologies;
Emerging image sensor technologies within the report include:
Hybrid image sensors – Adding an additional light-absorbing layer on top of a CMOS read-out circuit is a hybrid approach that utilizes either organic semiconductors or quantum dots to increase the spectral sensitivity into the SWIR region. Currently dominated by expensive InGaAs sensors, this new technology promises a substantial price reduction and hence the adoption of SWIR imaging for new applications such as autonomous vehicles.
Extended-range silicon – Given the very high price of InGaAs sensors, there is considerable motivation to develop much lower-cost alternatives that can detect light towards the lower end of the SWIR spectral region. Such SWIR sensors could then be employed in vehicles to provide better vision through fog and dust due to reduced scattering.
Thin film photodetectors – Detection of light over a large area, rather than at a single small detector, is highly desirable for acquiring biometric data and, if flexible, for imaging through the skin. Emerging approaches that utilize solution processable semiconductors offer a compelling way to produce large-area conformal photodetectors for applications such as under-display fingerprint detection.
Event-based vision – Autonomous vehicles, drones, and high-speed industrial applications require image sensing with a high temporal resolution. However, with conventional frame-based imaging, a high temporal resolution produces vast amounts of data that requires computationally intensive processing. Event-based vision is a new way of obtaining optical information that combines greater temporal resolution of rapidly changing image regions with much reduced data transfer and subsequent processing requirements.