Over the past few years, OmniVision Technologies has been developing ultra-small digital image sensors to suit the tight space needs of medical applications such a catheters or endoscopes. The company has developed what is reportedly the smallest image sensor available, the OV6948. Measuring 0.575mm x 0.575 mm, the sensor is smaller than a grain of rice.
To help OEMS design the sensor into medical applications, OmniVision is packaging the sensor into a tiny wafer-level camera module designated the OVM6948 CameraCubeChip. The module measures 0.65 mm x 0.65 mm, with a z-height of just 1.158mm. The module makes mass production of disposable medical imaging equipment possible and can be integrated into a catheter or endoscope with a diameter as small as 1.0 mm.
“As we go deeper inside the body, we need to go smaller and smaller,” said Tehzeeb S. Gunja, Medical Segment Lead for OmniVision, in an interview with FierceElectronics. “New procedures are possible due to small sensor size, in specialties such as cranial neurology, ophthalmology, spinal and cardiovascular—we can perform these more effectiively.” Gunga added that needles for biopsy, stents, vein harvesters, wound staplers, and surgical clip appliers are some applications requiring imaging in tight or inaccessible spaces.
The tiny camera module also addresses the challenges posed by reusable medical imaging equipment, including cross-contamination risks and inefficiencies due to high maintenance costs.
“There is a shift from reusable to disposable medical devices to deal with the problem of cross-contamination in reusable devices,” said Gunja.
With this camera’s small size and high 200 x 200 pixel, or 40 KPixel backside-illuminated resolution, high quality images can be captured from within the body’s narrowest blood vessels for neuro, ophthalmic, ENT, cardiac, spinal, urology, gynecology and arthroscopy procedures. Space-constrained dental, veterinarian and industrial applications can also benefit from the image sensor’s advanced design.
The OVM6948 is reportedly the only ultra-small “chip on tip” camera with backside illumination, which provides excellent image quality and better low-light performance to help reduce LED heat, along with improved sensitivity. It also allows for the use of superior lens technology over competing front-side illumination cameras in this class. This color analog camera uses the company’s OmniBSI+ technology for easier calibration in production. The module can be reflow soldered and has a 4-pin interface for simplified integration, which shortens time to market while reducing costs.
Other features include a wide 120-degree field of view and an extended focus range of 3 to 30 mm. Its image array can capture 200 x 200 resolution images and video at up to 30 frames per second, and its analog output can transmit over 4 meters with minimal noise. The camera consumes a low 25 mW to produce less heat for better patient comfort and flexible procedure durations.
The camera module is available now in volume production, along with an evaluation kit.