Confocal microscopy rejects out of focus light from the object by scanning a pinhole through the object and constructing the image point by point. Volume holographic imaging (VHI) systems with bright-field illumination have been proposed as an alternative to conventional confocal type microscopes. VHI systems are an imaging modality that does not require scanning of a pinhole or a slit and thus provides video rate imaging of 3-dimensional objects. However, due to the wavelength-position degeneracy of the hologram, these systems produce less than optimal optical sectioning because the high selectivity of the volume hologram is not utilized. In this dissertation a generalized method for the design of VHI systems applied to microscopy is developed. Discussion includes the inter-relationships between the dispersive, degenerate, and depth axes of the system. Novel designs to remove the wavelength-position degeneracy and improve optical sectioning in these systems are also considered. Optimization of a fluorescence imaging system and of dual-grating confocal-rainbow designs are investigated. A ray-trace simulation that integrates the hologram diffraction efficiency and imaging results is constructed and an experimental system evaluated to demonstrate the optimization method. This results in an empirical relation between depth resolution and design tolerances. The dispersion and construction tolerances of a confocal-rainbow volume holographic imaging system are defined by the Bragg selectivity of the holograms. It is found that a broad diffraction efficiency profile of the illumination hologram with a narrow imaging hologram profile is an optimal balance between field of view, construction alignment, and depth resolution. The approach in this research is directly applicable towards imaging ovarian cells for the detection of cancer. Modeling methods, illumination design, eliminating the wavelength degeneracy of the hologram, and incorporating florescence imaging capability are emphasized in this dissertation. Results from this research may be used not only for biomedical imaging, but also for the design of volume holographic systems for both imaging and sensor applications in other fields including manufacturing (e.g. pharmaceutical), aerospace (e.g. LIDAR), and the physical sciences (e.g. climate change).

This dissertation presents the theoretical and experimental exploration of active reflective components specifically for large-aperture adaptive optical zoom systems. An active reflective component can change its focal length by physically deforming its reflecting surface. Adaptive optical zoom (AOZ) utilizes active components in order to change magnification and achieve optical zoom, as opposed to traditional zooming systems that move elements along the optical axis. AOZ systems are theoretically examined using a novel optical design theory that enables a full-scale tradespace analysis, where optical design begins from a broad perspective and optimizes to a particular system. The theory applies existing strategies for telescope design and aberration simulation to AOZ, culminating in the design of a Cassegrain objective with a 3.3X zoom ratio and a 375mm entrance aperture. AOZ systems are experimentally examined with the development of a large-aperture active mirror constructed of a composite material called carbon fiber reinforced polymer (CFRP). The active CFRP mirror uses a novel actuation method to change radius of curvature, where actuators press against two annular rings placed on the mirror's back. This method enables the radius of curvature to increase from 2000mm to 2010mm. Closed-loop control maintains good optical performance of 1.05 waves peak-to-valley (with respect to a HeNe laser) when the active CFRP mirror is used in conjunction with a commercial deformable mirror.

QC 351 A7 no. 49 / The use of the two -dimensional Fourier transform to compute the form of the optical image has led to new insights into the form of images. The techniques involved are discussed in some detail, and the application to tolerancing of surface errors is used as an ex- ample of the results.

Many advances have occurred in the field of optical design during the past decade. Some of the newer topics and concepts associated with the design and use of optical systems are complex and require comprehensive understanding of theory, expertise in state-of-the-art technology, and extensive computer simulations. This dissertation focuses on development of practical methods and tools for successful lens design and evaluation of state-of-the-art imaging and illumination systems. The dissertation addresses several current topics in modern optical engineering and utilizes approaches to provide insights into the inner workings of optical systems. Examples of modern mobile camera lenses are provided to show how specific methods can help to better understand these lens designs and to expand the imaging capabilities of miniature camera systems. Two simple but effective real ray tracing methods for correcting chromatic aberrations in imaging systems are described. The proposed methods separate monochromatic and chromatic aberration correction into two independent problems. This two-step approach provides effective alternatives in correcting chromatic aberrations. A number of unique calculations have been performed and some novel and interesting theoretical results, including the fourth-order theory of irradiance changes in axially symmetric optical systems, are reported. The specific relationships between the irradiance distribution and wavefront aberration coefficients to fourth order are derived for the first time. The practical case of relative illumination at the image plane of an optical system is also discussed in some detail.

The Portable Satellite Laser Ranger (PSLR) is a light weight, highly portable satellite laser ranging system which employs many of the techniques and equipment types of larger fixed systems. It has a primary telescope aperture of 62 cm and uses a 150 ps pulse of 130 mJ at the second harmonic wavelength of 532 nm. The system is designed to use as little ancillary equipment as possible and only requires one small instrument rack and one PC based control computer. All of the control features of the system are based or installed in the control computer.The PSLR project at Curtin University was concerned with repairing and u p grading the PSLR to return the system to operational capacity. This involved the replacement of missing control components, repair of some hardware, modifications to the control program, and several calibration and operational tests. These tests showed that the PSLR system was capable of a ranging accuracy to fixed targets of 8.5 mm with an average accuracy of 23 mm. They showed that the PSLR was capable, in selective conditions, to track star ephemerides to less than 54. The mount error (standard deviation) over several orientations was shown to be 0.253° in elevation and 0.337° in azimuth.This dissertation will discuss; i) the operation of the equipment used with the PSLR and similar systems, the steps taken to repair or replace the necessary equipment, ii) the tests required to calibrate or evaluate various sub-systems of the PSLR and, iii) the results and conclusions drawn as a result.

<p>This dissertation explores computational optical imaging methods to circumvent the physical limitations of classical sensing. An ideal imaging system would maximize resolution in time, spectral bandwidth, three-dimensional object space, and polarization. Practically, increasing any one parameter will correspondingly decrease the others.</p><p>Spectrometers strive to measure the power spectral density of the object scene. Traditional pushbroom spectral imagers acquire high resolution spectral and spatial resolution at the expense of acquisition time. Multiplexed spectral imagers acquire spectral and spatial information at each instant of time. Using a coded aperture and dispersive element, the coded aperture snapshot spectral imagers (CASSI) here described leverage correlations between voxels in the spatial-spectral data cube to compressively sample the power spectral density with minimal loss in spatial-spectral resolution while maintaining high temporal resolution.</p><p>Photography is limited by similar physical constraints. Low f/# systems are required for high spatial resolution to circumvent diffraction limits and allow for more photon transfer to the film plain, but require larger optical volumes and more optical elements. Wide field systems similarly suffer from increasing complexity and optical volume. Incorporating a multi-scale optical system, the f/#, resolving power, optical volume and wide field of view become much less coupled. This system uses a single objective lens that images onto a curved spherical focal plane which is relayed by small micro-optics to discrete focal planes. Using this design methodology allows for gigapixel designs at low f/# that are only a few pounds and smaller than a one-foot hemisphere.</p><p>Computational imaging systems add the necessary step of forward modeling and calibration. Since the mapping from object space to image space is no longer directly readable, post-processing is required to display the required data. The CASSI system uses an undersampled measurement matrix that requires inversion while the multi-scale camera requires image stitching and compositing methods for billions of pixels in the image. Calibration methods and a testbed are demonstrated that were developed specifically for these computational imaging systems.</p> / Dissertation

Microstructures are usually fabricated on the surface of optical sheets to improve the optical characteristics. In this study, a new fabrication process with UV (ultraviolet) laser direct writing method is developed to embed microstructures inside the glass. Then the optical properties of glass such as reflection and refraction indexes can be modified. Single- and multi-layer microstructures are designed and embedded inside glasses to modify the optical characteristics. Both luminance and uniformity can be controlled with the embedded microstructures. Thus, the glass with inside pattern can be used as a light guide plate to increase optical performance. First, an optical software, FRED, is applied to design the microstructure configuration. Then, UV laser direct writing with output power: 2.5~ 2.6 W, repetition rate: 30 kHz, wave length: 355nm and pulse duration: 15ns is used to fabricate the microstructures inside the glass. The effect of pattern dimension such as the pitch, the layer gap, and the number of layer on the optical performance is discussed. Machining capacity of UV laser is ranging from micron to submicrometer; hence various dimensions of dot, line width, and layers can be easily embedded in the glass by one simple process. In addition, the embedded microstructures can be fabricated less damage and contamination. Finally, the optical performance of the glasses with various configurations is measured by using Spectra Colorometer (Photo Research PR650) and compared with the simulated results.

Space-based infrared Earth observation systems provide a unique opportunity for the detection of thermal variations on Earth&amp / #8217 / s surface or atmosphere. The objective of this study is to propose an optical design of a thermal imager that is suitable for flight on a micro-satellite platform at an altitude of 650 km, providing the necessary resolution requirements under the considerations of physical boundaries of the given platform. Before the optical design, the parameters which would strictly bound the optical system such as the infrared source, atmospheric transmission, the detector and optical materials for infrared as well as the working conditions for the microsatellite were examined. Simulations and further optimization efforts resulted with a high performance optical system design.

Aspheric and freeform surfaces are becoming more common as optical designs become more sophisticated and new generations of fabrication tools reduce cost. Unlike spherical surfaces, these surfaces are fabricated with processes that leave a signature or "structure" that is primarily in the mid-spatial frequency region. Tolerancing aspheric and freeform surfaces requires attention to both surface form and structured mid-spatial frequency fabrication errors. These structured surface errors are shown to create image artifacts such as ghosts, and ripples in the MTF profile. Spatial frequencies beyond "form" errors are often ignored or are modeled with statistical descriptors, which do not account for structured errors.This work explores and develops the theory to describe these errors without statistical assumptions. The analytic source of these artifacts in the image Point Spread Function and the Modulation Transfer Function are compared with computational models. The magnitudes of the image artifacts arising from structured surface errors are shown to be non-linear with surface height. It is also shown that multiple structured surface frequencies mix to create sum and difference diffraction orders that are not present in statistical models.An algorithm is developed that enables an optical designer to determine the important spatial frequencies and magnitudes of allowable errors given an MTF performance budget.

Head mounted projection display (HMPD) technology, as an alternative to conventional head mounted displays (HMD), offers a potential of designing wide field-of-view (FOV), low distortion optical see-through HMDs (OST-HMDs). Existing HMPD designs, however, suffer from problems of low luminance and low image resolution, which limits the applications of such information displays for the scenarios which require high luminance and high image fidelity. The design of a polarized head mounted projection display (p-HMPD) was recently proposed to overcome the challenge of low luminous efficiency in existing HMPD designs. Polarization management was employed to reduce the light loss caused by beamsplitting in an HMPD.The work in this dissertation focuses on the development and evaluation of an SXGA resolution, high efficiency p-HMPD system. The main contributions are as follows. First, the key elements in the polarization management scheme of a p-HMPD were selected and their polarization performances were characterized by measuring their Mueller matrices, based on which the overall display performance of a p-HMPD was analyzed.Second, based on a pair of ferroelectric liquid-crystal-on-silicon (FLCoS) microdisplays, a compact illumination unit and a light-weight projection system were designed, from which a p-HMPD prototype was built. Following the prototype implementation, a series of calibrations were performed to obtain correct color presentation, desired focusing setting, and optical system characteristics necessary for achieving accurate registration between virtual objects and their counterparts in the real world.Third, the imaging properties of a retroreflective screen which is an essential part of a p-HMPD or HMPD were studied and its effects on the image resolution of an HMPD system were further characterized.Finally, the performance of the system was evaluated through two objective user experiments, including a visual acuity assessment and a depth perception accuracy assessment.