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Discussed is a novel method of manufacturing an Angularly Sensitive Micro-Sensor (ASMS). The process
employed utilizes excimer laser ablation to write out the microlens on the curved surface of the master lens. This
master lens element is manufactured with fused optical fibers, such that if the registration is maintained, the light
from each microlens goes via the fiber to a specific pixel in a focal plane array (FPA). Such a system allows for a
field of view greatly in excess of 180 degrees. If local imaging is required for specific tasks the fiber can send the
angularly localized image to a pixel set. Image fusing may then be required.
Infrared and ultraviolet versions can be manufactured. A more general application allows for a multi-spectral
sensor. After one ASMS is constructed, then an inverse mask (mould) can be created and the monolithic sphere,
retaining its registration, is covered in liquid plastic and placed into the mould and the exact replica is re-created.
The advantage is low cost and rapid manufacture of the ASMS.
The paper focuses on this sensor as a Task-Oriented Optical Processing (TOP) system; where the processing is
performed primarily by the optics leaving a greatly reduced requirement for an electronic processor. This is a
critical issue for micro, insect sized platforms where the weight budget is devoted to the energy and propulsive
systems. An important aspect of this approach is that the sensor samples amplitude and angular space rather than
amplitude and position space as conventional sensors currently do. This makes the ASMS processing paradigm
completely different from conventional image processing. For example using several fiber/pixel elements to
comprise a UV polarimeter allows for simple storage and processing of vector elements for simple navigation. The
home position may be treated as "Look up table" reference matrix (RM). That base table can be modified to account
for the passage of time (and hence change in solar position from the UV polarimeter, as appropriate). A second
"real time" travel matrix (TRM) is then created. Eventually, a target matrix (TAM) would also be created. Simply
driving changes in the TRM towards the RM would be used for navigating the return trip back to home base. When
the difference between the two matrices goes to a null matrix the platform would be home.
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