SuperResolution Added to World’s Smallest Camera Module for Endoscopic Medical Imaging

OmniVision Technologies Inc., a developer of advanced digital imaging solutions, and Almalence Inc., one of the world’s leaders in computational imaging, have announced a joint solution that eliminates the conflict between camera size and resolution found in current medical imaging solutions. This is accomplished by dramatically increasing the resolution of images captured from the smallest parts of the anatomy during endoscopic and catheter procedures across all disciplines, such as neurology, ophthalmology, otolaryngology, cardiology, orthopedology, gynecology and urology.

The solution is based on OmniVision’s OVM6948 CameraCubeChip—the world’s smallest fully packaged, wafer-level camera module measuring 0.65mm x 0.65mm, with a z-height of just 1.158mm. Working in partnership with OmniVision, Almalence pre-tuned its SuperResolution algorithm, which is currently the de-facto standard for smartphone cameras, effectively increasing the OVM6948’s backside-illuminated resolution by 1.5x to 300×300 and boosting its signal-to-noise ratio (SNR) by up to 8dB for a total of about 42dB. These increases would otherwise double the image sensor and camera size, due to the required increase in pixel count.
 
The market research and strategy consulting company Yole Développement is expecting a 27 percent compound annual growth rate (CAGR) between 2019 and 2025,¹ reaching $241 million at the end of that period, for CIS camera modules for disposable endoscopes. “This market is being pushed by the addition of video and the shift toward small-diameter applications needing higher image resolutions. Additionally, medical trends are favoring single-use devices, including cross-contamination issues and strong regulations stemming from endoscope disinfection matters,” stated Jérôme Mouly, team lead analyst for sensing at Yole. “The ramp up is starting this year and will continue in the coming years as regulators enforce the use of disposable endoscopes for certain procedures, such as bronchoscopy, laryngoscopy and urology.”
 
The OVM6948 camera module integrates OmniVision’s OV6948 image sensor, which holds the Guinness World Record for “The Smallest Image Sensor Commercially Available” with its size of 0.575mm x 0.575mm. Because OmniVision’s unique CameraCubeChip optics are fabricated at the wafer level, they can be bonded to this image sensor to form a camera module that is 1.158mm high. This enables integration into an endoscope or catheter with a diameter of less than 2.0mm, thus allowing it to either reach deeper into the human anatomy or offer a larger array of endoscopic tools within its working channel.
 
“Until now, medical device designers were forced to make a tradeoff between size and resolution,” said Tehzeeb Gunja, director of medical marketing at OmniVision. “The dimensions of camera modules and their integrated image sensors are limited by the endoscope’s outer diameter. Additionally, to obtain a sufficiently bright image while limiting the heat dissipation of the LEDs at the distal tip, medical image sensors must have a relatively large pixel size. Almalence’s SuperResolution algorithm enhances the sensor’s resolution and image quality, enabling doctors and nurses to view its captured images on high-definition monitors and tablets.”
 
“The vast majority of high-end smartphones on the market today use our SuperResolution algorithm because we produce the greatest image quality within the limited space available, by reconstructing details beyond the physical limits of a sensor’s pixel count,” said Eugene Panich, CEO of Almalence Inc. “We have expanded our longstanding partnership with OmniVision in mobile imaging to bring our industry-leading algorithm to medical designers, enabling them to create small-diameter endoscopes with greater detail and better image quality than the image sensor would otherwise be capable of producing.”
 
Competing solutions include an image signal processor (ISP) that provides some level of upscaling as part of its processing pipeline. The functionality of these solutions ranges from the simple repetition of pixels, resulting in poor sharpness and image definition; to complex, computationally intensive solutions that provide upscaled images with relatively good image quality. However, none of the competing ISP solutions can provide the ability to capture more details than the sensor is capable of producing. Almalence’s SuperResolution algorithm uniquely increases the sensor’s effective resolution by not only making the image look sharper and smoother, but also reconstructing more details, as if it were captured with a higher resolution sensor. Additionally, the algorithm’s computational load is optimized to run on any major SoC or DSP, leaving plenty of headroom for other processing tasks.
 
References
¹ Source: Status of Medical Imaging Equipment and Detectors 2020 report, Yole Developpement.