Encoding of Complex Valued Composite Functions onto Spatial Light Modulators in Real-Time
Abstract
Spatial light modulators (SLM) are used as real-time programmable diffractive optics for potential applications to multi-object laser designation of moving objects. For real-time situations in which prior knowledge is unavailable, fast on-line design algorithms are required. The time requirements rule out many iterative design methods currently used for fixed pattern diffractive optics. Instead, encoding methods that map desired complex values onto the available modulation values provide the fastest realizations. As time permits, designs improved through limited iteration can be mapped to the SLM. Such a system, built around pseudorandom encoding (PRE) and its extensions was developed and experimentally demonstrated during the study. The most significant extension to PRE is the development of a method of complex-valued encoding that can be accomplished with as few as three discrete modulation values, and which can be generalized to any modulator characteristic. The pairwise blending of PRE with three other encoding algorithms (minimum distance encoding-MDE, modified minimum distance encoding-mMDE, error diffusion-ED) provides one or two parameters that can be adjusted quickly to produce better performance than either algorithm produces individually. The new design methods were experimentally demonstrated together with demonstrations of real-time design and continuous scanning of multiple spots on arbitrary and independent trajectories.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 07, 2000
- Accession Number
- ADA385480
Entities
People
- Robert W. Cohn
Organizations
- University of Louisville