FlatCam is a thin form-factor lensless camera that consists of a coded mask placed on top of a bare, conventional sensor array. Unlike a traditional, lens-based camera where an image of the scene is directly recorded on the sensor pixels, each pixel in FlatCam records a linear combination of light from multiple scene elements. A computational algorithm is then used to demultiplex the recorded measurements and reconstruct an image of the scene. FlatCam is an instance of a coded aperture imaging system; however, unlike the vast majority of related work, we place the coded mask extremely close to the image sensor that can enable a thin system. We employ a separable mask to ensure that both calibration and image reconstruction are scalable in terms of memory requirements and computational complexity. We demonstrate the potential of the FlatCam design using two prototypes: one at visible wavelengths and one at infrared wavelengths.

Optical sensors systems implement mappings between object and sensor spaces. Traditional systems are based on continuous models, in which both the objects and sensors are assumed to be in a continuous volume and the optical field propagation is also continuous. Since physical sensors are distributed discretely in the 3D phys-ical space, in practice an approximation must be made in traditional systems to fit the measurement data into the continuous model. This thesis explores an alterna-tive approach to studying the optical sensor system design based on a completely discrete model so that not only are the measurements on a finite point set but the reconstructed object is described with a finite point set instead of a continuous function. The thesis gives general discussion about the theoretical background of optical sensor systems and spatial mappings. Both the continuous and discrete models are discussed. A taxonomy is given to classify the design method for the discrete models. We summarize several approaches on how to design the optical sensor arrays with

FlatCam is a thin form-factor lensless camera that consists of a coded mask placed on top of a bare, conventional sensor array. Unlike a traditional, lens-based camera where an image of the scene is directly recorded on the sensor pixels, each pixel in FlatCam records a linear combination of light from multiple scene elements. A computational algorithm is then used to demultiplex the recorded measurements and reconstruct an image of the scene. FlatCam is an instance of a coded aperture imaging system; however, unlike the vast majority of related work, we place the coded mask extremely close to the image sensor that can enable a thin system. We employ a separable mask to ensure that both calibration and image reconstruction are scalable in terms of memory requirements and computational complexity. We demonstrate the potential of the FlatCam design using two prototypes: one at visible wavelengths and one at infrared wavelengths. I.

Coded aperture imaging has been used for astronomical applications for several years. Typical implementations used a fixed mask pattern and are designed to operate in the X-Ray or gamma ray bands. Recently applications have emerged in the visible and infra red bands for low cost lens-less imaging systems and system studies have shown that considerable advantages in image resolution may accrue from the use of multiple different images of the same scene – requiring a reconfigurable mask. Previously reported work focused on realising a 2x2cm single chip mask in the mid-IR based on polysilicon micro-opto-electro-mechanical systems (MOEMS) technology and its integration with ASIC drive electronics using conventional wire bonding. It employs interference effects to modulate incident light- achieved by tuning a large array of asymmetric Fabry-Perot optical cavities via an applied voltage and uses a hysteretic row/column scheme for addressing. In this paper we report on the latest results in the mid-IR for the single chip reconfigurable MOEMS mask, trials in scaling up to a mask based on a 2x2 multi-chip array and report on progress towards realising a large format mask comprising 44 MOEMS chips. We also explore the potential of such large, transmissive IR spatial light modulator arrays for other applications and in the current and alternative architectures.