Virtual Slide Scanner Optical Beam Shifting for Distortion-Free Imaging

The patent replaces the mechanical stage movement system with an optical beam shifting system. Instead of physically moving the stage or camera to capture multiple images, a beam shifting mechanism (such as a galvanometer mirror or acousto-optic modulator) deflects the light beam to scan across the sample, allowing the same image to be captured from different angular positions. This substitution eliminates mechanical inertia and positioning time, dramatically reducing image capture time while maintaining high-resolution composite image generation.

The patent employs periodic scanning of the light beam across the sample in a systematic pattern (e.g., raster scanning). The beam is rapidly swept back and forth across the field of view, capturing multiple angular positions of the same image in a periodic sequence. This periodic action allows efficient data acquisition without requiring continuous mechanical stage movement, reducing overall capture time while enabling high-resolution reconstruction through angular synthesis.

By replacing mechanical stage movement with optical beam shifting, the patent eliminates mechanical errors such as stage positioning inaccuracies, camera shake, and focus drift that occur during physical movement. The beam shifting mechanism maintains a fixed optical path and stationary camera, ensuring consistent focus and alignment across all captured images. This substitution directly addresses distortion and step difference problems by eliminating the source of mechanical instability.

The patent introduces a beam shifting mechanism as an intermediary between the fixed camera and the sample. Instead of moving the camera or sample directly, the beam shifter acts as a mediator that redirects light from different angular positions to the stationary camera sensor. This intermediary approach allows angular diversity to be captured while maintaining consistent optical alignment, preventing distortion and ensuring uniform image quality across the composite image.

The patent uses rapid periodic scanning of the light beam to capture multiple angular positions of the image in a single, continuous scanning motion. Instead of capturing images sequentially by moving the stage between shots, the beam is swept rapidly across the field of view in a periodic pattern, capturing all necessary angular data in one go. This periodic scanning approach obtains multiple images for distortion correction without requiring repeated stage movements, thus improving image quality without proportionally increasing capture time.

The patent maintains continuous useful action by keeping the camera stationary and continuously scanning the beam across the sample during a single capture sequence. The beam shifting mechanism operates continuously to sweep light from different positions onto the sensor, allowing uninterrupted data acquisition. This continuous scanning approach eliminates the idle time associated with stopping and repositioning mechanical stages between image captures, thereby obtaining multiple images for quality improvement without linearly increasing total capture time.