Microlens array architecture for avoiding ghosting in projected images
Light-field image data is processed in a manner that reduces projection artifacts in the presence of variation in microlens position by calibrating microlens positions. Approximate centers of disks in a light-field image are identified, and gridded calibration is performed, by fitting lines to disk centers along orthogonal directions, and then fitting a rigid grid to the light-field image. For each grid region, a corresponding disk center is computed, and a displacement vector is generated. For each grid region, the final disk center is computed as the vector sum of the grid region's geometric center and displacement vector. Calibration data, including displacement vectors, is then used in calibrating disk centers for more accurate projection of light-field images. In at least one embodiment, the imaging geometry is arranged so that disks are separated by a gap, so as to limit or eliminate ghosting.
1. A light-field image capture device, comprising:
a microlens array comprising a plurality of microlenses;
optics, configured to direct incoming light toward the microlens array; and
an image sensor, comprising a plurality of pixel sensors;
wherein:
the microlens array is disposed between the optics and the image sensor; and
each microlens in the microlens array is configured to project light onto a different region of the image sensor, each region comprising a subset of the pixel sensors, each region being horizontally separated from all other regions by a gap comprising at least one pixel sensor.
2. The device of claim 1 , wherein each region comprises a disk.
3. The device of claim 1 , wherein each region is circular.
4. The device of claim 1 , wherein no region touches any other region.
5. The device of claim 1 , wherein the optics comprise:
an aperture, configured to receiving incoming light; and
a main lens, configured to focus incoming light from the aperture toward the microlens array.
6. The device of claim 1 , wherein each pixel sensor is associated with a microlens based on calibrated coordinates of light passing through the microlens.
7. In a light-field image capture device comprising a microlens array comprising a plurality of microlenses, optics configured to direct incoming light toward the microlens array, and an image sensor comprising a plurality of pixel sensors, a configuration method, comprising:
positioning the microlens array between the optics and the image sensor; and
configuring each microlens in the microlens array to project light onto a different region of the image sensor, each region comprising a subset of the pixel sensors, each region being horizontally separated from all other regions by a gap comprising at least one pixel sensor.
8. The configuration method of claim 7 , wherein each region comprises a disk.
9. The configuration method of claim 7 , wherein each region is circular.
10. The configuration method of claim 7 , wherein no region touches any other region.
11. The configuration method of claim 7 , wherein the optics comprise:
an aperture, configured to receiving incoming light; and
a main lens, configured to focus incoming light from the aperture toward the microlens array.
12. The configuration method of claim 7 , further comprising associating each pixel sensor with a microlens based on calibrated coordinates of light passing through the microlens.