Coplanar Image Capture Sensors in Surgical Endoscopes

The patent transitions from distal-end lens-based imaging to proximal-end sensor-based imaging, fundamentally changing the spatial dimension where image capture occurs. By moving the image capture plane from the distal end (tip) to the proximal end (base) of the endoscope, the system eliminates the need for tiny distal lenses while maintaining a small outer diameter, as the optical path is folded back along the endoscope length.

The patent introduces a proximal end optical system with beam splitters and relay optics as intermediary components between the distal end scene and the proximal end sensors. This intermediary optical train allows light from the distal end to be redirected and focused onto the proximal end sensors, enabling high-quality imaging without requiring precise tiny lenses at the distal tip.

The patent merges the optical paths for left and right eye images into a single proximal end mounting plane. Both stereoscopic images are formed on the same proximal end structure, allowing the sensors to be mounted coplanarly with shared mechanical references. This combining of optical paths at the proximal end eliminates the need for complex separate alignment systems that would be required if sensors were mounted at the distal end.

The patent creates homogeneous mounting conditions for both image capture sensors by providing them with identical coplanar mounting surfaces, shared mechanical references, and equal optical path lengths from the distal end. This homogeneity in the mounting environment ensures that both sensors experience the same thermal, mechanical, and optical conditions, eliminating the need for individual calibration of each sensor's artifacts.

The patent transitions the image capture location from the distal end (tip) to the proximal end (base) of the endoscope, fundamentally changing the spatial dimension where imaging occurs. This dimensional shift allows the use of large, easily focused lenses at the proximal end while maintaining small distal end dimensions, eliminating the need for difficult-to-focus tiny distal lenses and the associated manufacturing precision problems.

The patent extracts the image capture function from the distal end optical system and relocates it to the proximal end. By taking out the sensors and main optical processing from the constrained distal end environment, the system eliminates the manufacturing precision issues associated with tiny distal lenses, as all critical optical components are now located at the proximal end where manufacturing and alignment are much easier.

The patent exploits the longitudinal dimension of the endoscope by folding the optical path back along its length to bring large sensors to the proximal end. This dimensional exploitation allows the distal end to remain small for patient comfort while the proximal end houses large sensors with many pixels, effectively decoupling the size constraints from the image quality requirements.

The patent implements a nested optical structure where the optical path is folded back within the endoscope's longitudinal space. The optical train including beam splitters and relay optics is nested within the endoscope body, allowing light from the distal tip to traverse back through the endoscope length to reach large proximal sensors, effectively nesting the imaging function within the constrained form factor.