This PDF file contains the front matter associated with SPIE Proceedings Volume 7787, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and the Conference Committee listing.

The fabrication and optical performance of a Cassegrain type telescope that employs a field corrector depends on the conic constant of the primary mirror. The design of the field corrector calls for different choices on mirror asphericity which imply a departure from the nominal Cassegrain or Ritchey-Chrétien solutions. This departure may not be acceptable given that the telescope would not operate properly without the field corrector. In this paper we present a study of the variation of mirror conic constant and field corrector choice of some existing telescopes. We also discuss some trade-offs in the design of a telescope with a field corrector.

In illumination optics an important design task is to create a light source with a certain intensity profile. One way to achieve this is to use LEDs and secondary optics that use freeform surfaces. Freeform lens design is a very powerful tool with many sophisticated design techniques. However, it is not always necessary to use difficult techniques or complicated software algorithms to design a freeform lens surface. This paper presents a method for designing a radially-symmetric freeform lens using a spreadsheet. The spreadsheet designs freeform lenses that transform a Lambertian (cosine[theta]) intensity profile from a light source to any output profile of the form (cosine^N[theta]) where N is a real number. The input and output are radially symmetric, and the lens controls the angular extent (cone half-angle) of the output beam. Several example lenses are presented and one lens is analyzed with a raytrace simulation.

Using the Simultaneous Multiple Surface method in 2D (SMS2D), we present a fast catadioptric objective with a wide field of view (125°×96°) designed for a microbolometer detector with 640×480 pixels and 25 microns pixel pitch Keywords: Infrared lens design, thermal imaging, Schwarzschild configuration, SMS2D, wide field of view, driving cameras, panoramic systems

This paper describes a process for designing a faceted freeform Fresnel lens. Where a traditional Fresnel lens uses a profile revolved around a central axis, a freeform Fresnel lens uses individual triangular or trapezoidal facets that comprise a freeform surface. This type of lens combines the capability of a freeform surface with the benefits of a Fresnel lens, in particular: thin profile, low cost, small size, and relatively simple geometry calculations. An algorithm is presented to design such a lens that generates an output intensity distribution without depending on symmetry in the light source, the lens aperture, or the output intensity distribution. Two example systems are presented, demonstrating how a freeform Fresnel lens can reshape a beam of light without relying on symmetry.

Today, both military and civilian applications require miniaturized and cheap optical systems. The miniaturization of imaging systems leads to breakthroughs in optical design. Multichannel systems, inspired by the compound eyes of insects, offer great opportunities as the principle is to divide the information contained in the whole scene into the different optical channels. An interesting approach is to take advantage of the infrared focal plane array technology and environment to integrate these systems near the detector, leading to very compact architectures. This paper presents a compact optical architecture based on a multichannel imaging system entirely integrated in the dewar used to cool the detector. This work gives encouraging results to prepare the next step in the miniaturization of optical systems, which is the integration of the imaging function directly on the focal plane array (wafer-level integration), leading to the design of an on-chip infrared camera.

The resolution of conventional space telescopes is limited by the size of their aperture. High resolution telescopes must have large aperture primary mirrors - heavy, expensive and costly to deliver to orbit. In contrast, micro-satellites are small, relatively inexpensive, and are often "hitch-hiked" with other payload to orbit. However, the size of micro-satellites limits them to small aperture optics. By combining multiple images from a suitably-designed telescope with several small mirrors and digitally post-processing the combined image, it is possible to obtain higher resolution. The optical layout and the digital post-synthesis for these proposed micro-satellite telescopes are presented and analyzed.

Computational imaging technology can capture extra information at the sensor and can be used for various photographic applications, including imaging with extended depth of field or depth extraction for 3D applications. The depth estimation from a single captured photograph can be achieved through a phase coded lens and image processing. In this paper, we propose a new method to design a phase coded lens, using a blur metric (BM) as the design criterion. Matlab and Zemax are used for the co-optimization of optical coding and digital image process. The purpose of the design is to find a curve for which the BM changes continuously and seriously within a distance range. We verified our approach by simulation, and got a axial symmetric phase mask as the coded lens. By using a pseudo-random pattern which contains uniform black and white patches as the input image, and the on-axis point spread function (PSF) calculated from Zemax, we can evaluate the BM of the simulated image which is convoluted by the pseudo-random pattern and PSF. In order to ensure the BM curve evaluated from the on-axis PSF represents the result of the whole field of view, the PSF is also optimized to get high off-axis similarity.

This paper describes a snapshot Mueller matrix polarimeter by wavelength polarization coding. This device encodes polarization states in the spectral domain through use of a broadband source and high-order retarders. This allows one to measure a full Mueller matrix from a single spectrum whose acquisition time only depends on the detection system aperture. The theoretical fundamentals of this technique are developed prior to validation by experiments. The setup calibration is described as well as optimization and stabilization procedures. Then, the polarimeter is used to study, by time-resolved Mueller matrix polarimetry, the switching dynamics within a ferroelectric liquid crystal cell.

Pupil plane filtering provides a convenient technique for modifying the point spread function. Such modifications are used in many practical applications that require enhancement of selective frequency band in images. Also, in many new imaging paradigms, acquisition of 3D image information calls for tailoring of the 3D point spread function. This can be achieved by suitable pupil plane filtering, preferably by phase filters. By using a pupil plane filter with an array of concentric annuli, the point spread function can be tailored in a fashion such that a narrow central lobe is surrounded by neighboring lobes of low amplitude, with one or more lobes of high amplitude spaced far away from the center. In our study we intend to explore the use of phase annuli as pupil filters in tailoring of both transverse and axial resolution. Determination of such phase filters in accordance with a set of prespecified requirements for amplitude/intensity distribution around the focus constitutes a problem of nonlinear optimization. This paper reports some results of our preliminary investigations on an application of evolutionary programming in solving this problem to obtain globally or quasi-globally optimum solutions.

We have developed the dual camera image guidance system for autonomous vehicle based on the fast focusing and the spot RGB spectrum similarity operation. The fast focusing catches the distance information of outside world as a whole. The spot RGB spectrum similarity operation finds the object surface portion in the image. Our fast focusing algorithm works precisely on the differential image such as the Daubechies wavelet transformed high pass image, the Roberts image, Prewitt image, Sobel image and the Laplacian image. The spot RGB spectrum similarity operation for the surface detection comes from the idea of the laser range finder. The illuminated coherent laser reflects on the object surface and the reflected laser is detected on the spectrum band detector. The RGB spectrum distribution on the selected spot on one camera can give the expected similar spectrum information on the position-matched spot on another camera if the selected spot corresponds to the surface of the object. We move the autonomous vehicle based on the distance detection and the surface detection of the outside world due to the controlled dual color camera system. Our autonomous vehicle is equipped with the controllable independent four wheels drive. This vehicle can avoid the object geometrically even if it is just in front of the object. We mount the dual camera image guidance system on two axes jimbal system to aim the object in space.

This paper describes the optimization of fingernail sensors for measuring fingertip touch forces for human-computer interaction. The fingernail sensor uses optical reflectance photoplethysmography to measure the change in blood perfusion in the fingernail bed when the fingerpad touches a surface with various forces. In the original fingernail sensor, color changes observed through the fingernail have been measured by mounting an array of six LEDs (Light Emitting Diodes) and eight photodetectors on the fingernail in a laterally symmetric configuration. The optical components were located such that each photodiode had at least one neighboring LED. The role of each of the photodetectors was investigated in terms of the effect of removing one or more photodetectors on force prediction estimation. The analysis suggested designing the next generation of fingernail sensors with less than eight photodetectors. This paper proposes an optimal redesign by analyzing a photographic catalog composed of six different force poses, representing average fingernail coloration patterns of fifteen human subjects. It also introduces an optical model that describes light transmission between an LED and a photodiode, and predicts the optimal locations of the optoelectronic devices in the fingernail area.

To reduce the cost of LCD backlight unit (BLU) and raise efficiency, a direct LED BLU consisted of double-triangular structures was proposed to control the light from RGB side emitting LEDs. A genetic algorithm was used to search the optimal parameters of the shape of the double-triangular structures and the layout of the LEDs. A switch mode constant current control driver with a PWM controlled converter switch was used to maintaining the constant current output for the variable numbers of the LEDs in this paper. From the simulation results showed that without the diffuser, the brightness uniformity on the 25-point test was 93.44% for a 22" direct LED backlight unit with a thickness of 30mm with the optimized double-triangular structure. And the experiment result showed that the brightness uniformity and color uniformity were 85.61% and 0.021 for a small size test unit.

A miniature projecting system with dimension of 20 mm in length, 12 mm in width, and 10 mm in height suitable for mobile devices is presented in this paper. This novel projecting system consists of an optical system with two lenses, a liquid crystal display (LCD) device, a collimating tube, and a 1 W high power light-emitting diode (LED) with wavelength of 525 nm. It projects a clear and bright image of 4.5 cm × 1.3 cm which displays 24 digits onto the palm at a distance of 20 cm in a room with light on. The projector can be fabricated easily at low cost. Miniaturization is achieved in this system so that it can be equipped into thin mobile phones.

An optical induction generator is designed and tested to determine the feasibility of using radiometric forces for renewable energy applications. Through modifications with electromagnetic induction components Crooke's radiometer is transformed into an electric generator. Initial designs allow for the variation in the orientation and numbers of magnetic poles as well as the characteristics of the armature (number of turns, wire gauge, location). Prototype devices are analyzed to obtain proof-of-concept. Verification is achieved by real time variation of incident electromagnetic energy directly corresponding to angular frequency of the generator and the characteristics of the produced EMF waveform. I-V characteristic curves illustrate the generator performance. Radiometric generators with two and four magnetic poles are shown to produce alternating current (AC) signals, on the order of millivolts, which vary linearly in both amplitude and frequency in respect to the rotational frequency of the radiometric generators.

An apertureless near-field scanning optical microscope (a-NSOM) setup is described. Special consideration is given to important system components. Surface plasmons are defined, as is their relationship to a- NSOM and their interaction with the scanning probe tip. We used this set-up to measure a metal-dielectric-metal (MDM) antenna integrated with a quantum cascade laser (QCL). The former is introduced and described. The role of the atomic force microscope (AFM) in the experiment is laid out and explained. Finally, the lock-in amplifier is explained. Next, the system setup is introduced and explained from the point of view of the light path taken by light generated in the laser. Finally, results are given for the MDM single nanorod antenna and the coupled MDM nanorod antenna. Simulation, topography, and NSOM images are shown. Lastly, several experimental issues are discussed as well as other types of NSOM.

Now, Military demands focused attention on small and light-weight system development. Above all, UAV(Unmanned Aerial Vehicle) is necessary to reduce weight of equipments. Therefore, we invest some expense in many years so that it might design more light optical system for UAV. Consequently, we can build new miniaturization and light-weight system. The most important thing is the system using just two motors for continuous zoom(x3 ~ x20), NUC(nonuniformity correction), Narcissus, Athermalization, and auto-focus functions. An MTF (modulation transfer function) and a detection range are also satisfied by the demands. We use CODE V and NVTherm program for design and analysis.

In this paper we will be discussing different techniques for producing superresolved point-spread functions (PSFs) that are based on amplitude and phase pupil masks. We propose a novel method of producing elongated superresolved pointspread functions (PSFs) using a combination of a vortex phase modulation technique and elliptical amplitude masking at the pupil of an optical system. When compared to diffraction-limited PSFs produced by an optical system with the same pupil ellipticity, the proposed method produces a significant reduction in PSF width. The proposed technique can be applied to a variety of applications, including scanning microscopy and optical micromanipulation, as well as highdensity optical data storage.

A novel car camera lenses have been designed. To reduce the cost, the system gives up the glued lenses. The whole optical system is made of six separated lenses and an IR-Cut Filter, among which there is two aspheric lenses and four spherical lenses. All lenses are made of glass. The resolutions of car camera system is three million pixels and the field angle is 150°.The Tangential MTF is 0.2 at spatial frequency of 300 cycles/mm when field angle is equal to 150°. The axis MTF is 0.7 at spatial frequency of 150 cycles/mm. The overall length of system is 18.23mm. The F-number is 2.8 and the effective focus length is 1.6mm. The new-designed car camera lenses can provide high-resolutions and very wide field angle. At the same time, the glass structure of lenses enjoys better thermal and mechanical stability than polymer lenses. The novel car-camera lenses will be then tested in the experiment.

A novel method of free space passive optical coupling to completely embedded fiber Bragg grating (FBG) sensors has been investigated. Fiber optical sensors have attracted intense research and commercial interest. Specifically, fiber Bragg grating (FBG) sensors have shown great utility for integrity management and environmental sensing of composite structures. One major drawback of FBG sensors, however, is that they suffer from cumbersome and fragile techniques for bringing the sensing light into and out of the structures. In our previous publication, we have demonstrated surface normal free space coupling into embedded FBG sensors with 45-degree-angled mirrors integrated into fibers as the coupling technique. These previous studies, however, required physical coupling to detect and analyze the light transmitted through the FBG. In this paper, we successfully couple free space light into and out of an un-embedded FBG sensor using multimode fiber (MMF) spliced to SMFBG with 45-degree-angled mirrors fabricated onto both MMF and SMFBG on a polishing wheel. We also present a manual polishing technique to integrate mirrors onto MMF and SMF (without Bragg grating) embedded in a composite material, and successfully measure the coupling into and through these embedded optical fibers. With this approach, no pigtailing is needed, and the FBG sensors can be completely embedded inside the structures, greatly increasing system simplicity and robustness.