Established capturing properties like image resolution need to be described thoroughly in complex multidimensional cap turing setups such as plenoptic cameras (PC), as these in troduce a trade-off between resolution and features such as field of view, depth of field, and signal to noise ratio. Mod els, methods and metrics that assist exploring and formulating this trade-off are highly beneficial for study as well as design of complex capturing systems. This work presents how the important high-level property lateral resolution is extracted from our previously proposed Sampling Pattern Cube (SPC) model. The SPC carries ray information as well as focal properties of the capturing system it models. The proposed operator extracts the lateral resolution from the SPC model throughout an arbitrary number of depth planes resulting in a depth-resolution profile. We have validated the resolution op erator by comparing the achieved lateral resolution with pre vious results from more simple models and from wave optics based Monte Carlo simulations. The lateral resolution pre dicted by the SPC model agrees with the results from wave optics based numerical simulations and strengthens the con clusion that the SPC fills the gap between ray-based mod els and wave optics based models, by including the focal in formation of the system as a model parameter. The SPC is proven a simple yet efficient model for extracting the depth based lateral resolution as a high-level property of complex plenoptic capturing system.

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Complex multidimensional capturing setups such as plenoptic cameras (PC) introduce a trade-off between various system properties. Consequently, established capturing properties, like image resolution, need to be described thoroughly for these systems. Therefore models and metrics that assist exploring and formulating this trade-off are highly beneficial for studying as well as designing of complex capturing systems. This work demonstrates the capability of our previously proposed sampling pattern cube (SPC) model to extract the lateral resolution for plenoptic capturing systems. The SPC carries both ray information as well as focal properties of the capturing system it models. The proposed operator extracts the lateral resolution from the SPC model throughout an arbitrary number of depth planes giving a depth-resolution profile. This operator utilizes focal properties of the capturing system as well as the geometrical distribution of the light containers which are the elements in the SPC model. We have validated the lateral resolution operator for different capturing setups by comparing the results with those from Monte Carlo numerical simulations based on the wave optics model. The lateral resolution predicted by the SPC model agrees with the results from the more complex wave optics model better than both the ray based model and our previously proposed lateral resolution operator. This agreement strengthens the conclusion that the SPC fills the gap between ray-based models and the real system performance, by including the focal information of the system as a model parameter. The SPC is proven a simple yet efficient model for extracting the lateral resolution as a high-level property of complex plenoptic capturing systems.

Sensitivity improvement is a challenging issue in miniature pressure sensors. To improve sensitivity and linearity of the device, a wide micro beam structure has been proposed to gauge capacitance changes caused by the applied pressure in a capacitive MEMS fingerprint sensor. Bending behavior of the device and the effect of the protrusion geometry on partial loading of the micro beam has been analytically investigated. Based on the idea of efficient loading of the wide micro beam, an improved design for the capacitive fingerprint sensor is developed to increase sensitivity. It is shown with FEM simulations that the micro wide beam design is superior to the common membrane based MEMS fingerprint sensors in terms of sensitivity and linearity.

Abstract.A novel MEMS capacitive pressure sensor array is designed and fabricated for fingerprint acquisition application. Based on analytical investigations and FEM analysis, the designed structure of pressure sensor cells assist from an aluminum clamped-clamped wide beam as the movable electrode of variant capacitor, instead of usual membrane structure. A rectangular base T-shape protrusion is also used on top of the deflecting electrode to concentrate pressure and increase the sensitivity. Proven by the real test of the fabricated sensor structure, this design has enhanced sensitivity and linearity of the device compared to all membrane based reported prototypes without crossing the dpi limits. Structural modifications have resulted in a simpler fabrication process as well.