This work presents a numerical simulation of a Hartmann-Shack wavefront sensor (WFS) that assesses the impact of integrated electronic circuitry on the sensor performance, by evaluating a full detection chain encompassing wavefront sampling, photodetection, electronic circuitry and wavefront reconstruction. This platform links dedicated C algorithms for WFS to a SPICE circuit simulator for integrated electronics. The complete codes can be easily replaced in order to represent different detection or reconstruction methods, while the circuit simulator employs reliable models of either off-the-shelf circuit components or custom integrated circuit modules. The most relevant role of this platform is to enable the evaluation of the applicability and constraints of the focal plane of a given wavefront sensor prior to the actual fabrication of the detector chip. In this paper, we will present the simulation results for a Hartmann-Shack wavefront sensor with an orthogonal array of quad-cells (QC) integrated along with active-pixel (active-pixel sensor (APS)) circuitry and analog-to-digital converters (ADC) on a “complementary metal oxide semiconductor” (CMOS) process and deploying a modal wavefront reconstructor. This extended simulation capability for wavefront sensors enables the test and verification of different photosensitive and circuitry topologies for position-sensitive detectors combined with the simulation of sampling microlenses and reconstruction algorithms, with the goal of enhancing the accuracy in the prediction of the wavefront-sensor performance before a detector CMOS chip is actually fabricated.

The wavefront reconstruction diagram has come to supply the need in literature of an ampler vision over the many methods and optronic devices used for the reconstruction of wavefronts and to show the existing interactions between those. A computational platform has been developed using the diagram's orientation for the taking of decision over the best technique and the photo sensible and electronic structures to be implemented. This work will be directed to an ophthalmological application in the development of an instrument of help for the diagnosis of optical aberrations of the human eye.KEY WORDS: Computational test bench, Flow Chart, wavefront sensors and ophthalmology.

This work presents an integrated pixel topology that promises to offer superior performance in a Hartmann-Shack Wavefront Sensor (WFS) with an orthogonal array of Quad Cells serving as Position-Sensitive Detectors. The readout integrated circuit for each photodiode is fully compliant to any standard CMOS microelectronics technology and is advantageously tolerant to high background illumination levels whereas maintaining both high linearity and high sensitivity. To assess the operation of this pixel on the focal-plane array of the WFS, we developed a computational platform encompassing a full detection chain comprising wavefront sampling, photodetection, electronic circuitry and wavefront reconstruction. It couples an algorithm written in C to SPICE (Simulated Program with Integrated Circuits Emphasis). The platform is technology agnostic and flexible, enabling easy modification to represent different detection or reconstruction methods. The results obtained with the proposed pixel have been compared to those obtained with a conventional pixel in CMOS image sensor.

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