A new camera module with quadruple the resolution of its predecessor, at 400 × 400, or 160 Kpixels, provides clear images inside the body’s farthest recesses. The OVMed® OCHTA module from Omnivision , integrates the company’s CameraCubeChip™ wafer-level technology, enabling it to match the world’s smallest size of its predecessor, at 0.65 × 0.65 mm, for deep anatomical access.

This technology also allows for the integration of OmniVision’s new higher-resolution OH0TA image sensor, the size of which is smaller than the Guinness World Record held by its predecessor, along with signal processing and wafer-level optics in a single compact package. With OCHTA camera modules, endoscope, catheter, and guidewire OEMs can now develop mass-produced, single-use devices with 1–2 mm optical diameters and higher resolution to address the many challenges posed by reusable equipment, including cross-contamination risks and high maintenance costs.

“Previously, medical procedures on the body’s smallest anatomy were performed either blind or with low quality images from fiberscopes, as existing cameras were too big and reusable endoscopes were not cost effective,” says Aaron Chiang, marketing director at OmniVision. “The OCHTA wafer-level camera module maintains the industry’s smallest size while quadrupling the resolution for single-use endoscopes, catheters and guidewires, which reduce the cross-contamination risks and downtime inefficiencies of reusable devices, as well as costs from their repairs, preprocedural testing and sterilization.”

The wafer-level block diagram.

This module’s small size enables devices that can reach deep into the body for neuro, ophthalmic, ENT, cardiac, spinal, urology, gynecology and arthroscopy procedures, as well as dental and veterinary diagnosis and surgery. Alternatively, its unique size gives medical device OEMs the flexibility to create a larger-diameter scope with a larger working channel. By integrating the image sensor, signal processor and wafer-level optics in a single compact package, the OCHTA also reduces the complexity of dealing with multiple vendors while increasing supply reliability and speeding development time. Furthermore, unlike traditional cameras, all CameraCubeChip modules are reflowable. This means they can be mounted to a printed circuit board simultaneously with other components using automated surface-mount assembly equipment, which increases quality while reducing assembly costs.

The integrated OH0TA image sensor is built on OmniVision’s PureCel® Plus-S stacked die technology, which enables this module’s increased resolution at 30 frames per second. Additionally, this next-generation pixel technology provides higher color fidelity and excellent low light sensitivity of 3600 mV/lux-sec, along with a high signal-to-noise ratio of 37.5 dB for crisper images. It also offers higher full well capacity (FWC), zero blooming and 20 percent lower power consumption of 20 mW for greater patient comfort and longer procedure durations, while reducing noise for crisper images. These images are further improved by the sensor’s new exposure and gain control settings, which allow endoscope designers to fine-tune captures — prior to processing — for the best possible video quality under the lighting conditions of specific procedures.

Other key features include a wide 120 degree field of view and an extended focus range of 3–30 mm. This module also supports a 4-wire interface, as well as raw analog data output, both of which can transmit via cables as long as 4 m with minimal signal noise.

“It is not just the high resolution. It’s the combination of the higher resolution size and the low light sensitivity,” says Ehsan Ayar, medical product marketing manager at OmniVision. “As a result of the smaller size and lower and better low light sensitivity, doctors can get to places where they have not been able to get to before. In endoscopy, for example, they are like a tree: they are branching off with more and more branches that are narrower and narrower. “So, let’s say, in the case of a stroke, you want to know where there is a blockage that may be in smaller arteries. If you don’t have a small size like this, you cannot get there.”

The OCHTA camera module uses CameraCubeChip™ wafer-level camera technology to match the size of it predecessor while integrating the new OH0TA image sensor.

The OH0TA’s increased resolution allows higher quality color images to be captured from within the body’s smallest organs, enabling medical devices to reach deeper into the body for procedures such as neuro, ophthalmic, ENT, cardiac, spinal, urology, gynecology and arthroscopy, as well as dental and veterinary diagnosis and surgery. Additionally, the sensor’s lower power consumption reduces “chip on tip” camera heat for greater patient comfort and longer procedure durations, while also reducing noise for crisper images.

“The trend toward minimally invasive procedures continues to grow, due to their greater success rates and shorter patient recovery times. However, for the narrowest areas of the anatomy, particularly in neuro and cardiac surgeries, previous sensors did not have the necessary combination of high resolution and extremely small size,” says Ayar. “The OH0TA is the world’s first sensor to offer this combination, enabling significant endoscope improvements, especially in comparison to traditional videoscopes made with optical fibers, which have limited resolution, poor imager quality and high cost.”

Yole Développement (Yole) predicts continued strong demand in single-use medical endoscopes, with an expected 27 percent CAGR between 2019 and 2025. Yole also predicts a US$241 million market at the end of that period for CMOS image sensor camera modules. “Reinforced by the COVID-19 pandemic, regulations from health authorities are strongly changing the endoscopy industry landscape,” explained Jérôme Mouly, team lead analyst, sensing and actuating at Yole. “The aim is to avoid cross contamination in high risk imaging procedures that use tiny endoscopes, like bronchoscopies, ureteroscopies or pediatric imaging diagnostics. Key requirements from caregivers include strong miniaturization of cameras, image quality increases as well as high contrast at low power to avoid any heat disturbances during procedures.”

To achieve this increase in resolution, along with a smaller pixel size and optical format, the OH0TA is built on OmniVision’s PureCel® Plus-S stacked die technology. This next-generation pixel technology also provides higher color fidelity and excellent low light sensitivity of 3600 mV/lux-sec, along with a high signal-to-noise ratio of 37.5 dB for crisper images. Additionally, PureCel Plus-S enables the OH0TA’s higher full well capacity (FWC), zero blooming and lower power consumption.

“The whole idea is to have an affordable camera module that you can put inside a disposable endoscope,” says Tehzeeb Gunja, medical director of the marketing segment at Omnivision.