Coded Aperture Projection | ACM ToG 2010

Max Grosse, Gordon Wetzstein, Anselm Grundhoefer, Oliver Bimber

Coding a projector’s aperture plane with adaptive patterns together with inverse filtering allow the depth-of-field of projected imagery to be increased.

Abstract

Coding a projector’s aperture plane with adaptive patterns together with inverse filtering allow the depth-of-field of projected imagery to be increased. We present two prototypes and corresponding algorithms for static and programmable apertures. We also explain how these patterns can be computed at int eractive rates, by taking into account the image content and limitations of the human visual system. Applications such as projector defocus compensation, hig h-quality projector depixelation, and increased temporal contrast of projected video sequences can be supported. Coded apertures are a step towards next-generation auto-iris projector lenses.

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Citation

M. Grosse, G. Wetzstein, A. Grundhoefer, O. Bimber. Coded Aperture Projection. ACM Transactions on Graphics 29, 3, 2010.

BibTeX

@article{Grosse:2010:CodedApertureProjection,
author = {M. Grosse and G. Wetzstein and A. Grundhoefer and O. Bimber},
title = {{Coded Aperture Projection}},
journal = {ACM Trans. Graph.},
volume = {29},
number = {3},
year = {2010},
publisher = {ACM},
pages = {1–12},
address = {New York, NY, USA}
}

Two prototypes: a static attenuation mask integrated into the aperture plane of a projector improves digital defocus compensation through inverse filtering (left). Replacing the aperture with a transparent liquid crystal array allows dynamic attenuation mask patterns to be encoded (right). We compute the adaptive patterns by optimizing for light throughput while preserving spatial frequencies that are perceivable by a human observer. Both approaches significantly improve depth-of-field through inverse light filtering when compared to circular aperture stops.While static coded apertures are easier to realize and less expensive, adaptive coded apertures are more effective.

Two prototypes: a static attenuation mask integrated into the aperture plane of a projector improves digital defocus compensation through inverse filtering (left). Replacing the aperture with a transparent liquid crystal array allows dynamic attenuation mask patterns to be encoded (right). We compute the adaptive patterns by optimizing for light throughput while preserving spatial frequencies that are perceivable by a human observer. Both approaches significantly improve depth-of-field through inverse light filtering when compared to circular aperture stops.While static coded apertures are easier to realize and less expensive, adaptive coded apertures are more effective.