This PDF file contains the front matter associated with SPIE Proceedings Volume 7210, including the Title Page, Copyright information, Table of Contents, Introduction, and Conference Committee listing.

By combining unique light sources, a Texas Instruments DLP system and a microscope, a submicron dynamic patterning system has been created. This system has a resolution of 0.5 microns, and can illuminate with rapidly changing patterns of visible, UV or pulsed laser light. This system has been used to create digital masks for the production of micron scale electronic test circuits and has been used in biological applications. Specifically we have directed light on a sub-organelle scale to cells to control their morphology and motility with applications to tissue engineering, cell biology, drug discovery and neurology.

Cataract surgery with IOL implantation is performed on millions of patients every year. Despite 25 years of technological innovation, post-surgical refractive errors have remained a problem. Now these errors can be corrected using Calhoun Vision, Inc's light adjustable lens (LAL). The correction is accomplished by implanting a light-sensitive lens, then illuminating it with a spatially varying irradiance profile during a postoperative treatment. This irradiance profile is provided by a Light Delivery Device (LDD), which projects an image of a Texas Instruments DMD onto the implanted lens. Commercial sales of this system began in the summer of 2008 in Europe; US clinical trials began in January 2009.

Phototransistor-based Optoelectronic Tweezers (Ph-OET) enables optical manipulation of microscopic particles in physiological buffer solutions by creating electrical field gradients around them. A spatial light pattern is created by a DMD based projector focused through a microscope objective onto the phototransistor. In this paper we look into what differences there are in the trap stiffness profiles of HeLa cells trapped by Ph-OET compared to previous a-Si based OET devices. We find that the minimum trap size for a HeLa cell using a phototransistor with pixel pitch 10.35μm is 24.06μm in diameter which can move cells at 20μms^-1 giving a trap stiffness of 8.38 x 10^-7 Nm^-1.

In vision and color research, it is often desirable to precisely control the spectral content of light stimuli. Some demanding research applications require replicating or producing natural or novel complex spectral illumination. However, complex spectral distributions, common in the real world, often prove difficult to simulate in the lab. Past researchers have combined LCD technologies with broadband sources and wavelength dispersing elements, such as gratings, to produce approximations to natural distributions. These devices have been limited in contrast, temporal resolution, and precision by the nature of the LCD itself. We show here how a spectrally-dispersed broadband source modulated with Digital Light Processor (DLP) technology provides for rapid and precise spectral shaping of visual stimuli at intensity and precision levels previously unattainable using other light modulating technologies, and present a sample application consisting of data from color vision experiments designed to probe the visual system's differential response to narrow versus broad band color stimuli.

We describe a novel digital light processing, DLP hyperspectral imaging system for visualizing chemical composition of in vivo tissues during surgical procedures non-invasively and at near video rate. The novelty of the DLP hyperspectral imaging system resides in (1) its ability to conform light to rapidly sweep through a series of preprogrammed spectral illuminations as simple as a set of contiguous bandpasses to any number of complex spectra, and (2) processing the reflected spectroscopic image data using unique supervised and unsupervised chemometric methods that color encode molecular content of tissue at each image detector pixel providing an optical biopsy. Spectral illumination of tissue is accomplished utilizing a DLP® based spectral illuminator incorporating a series of bandpass spectra and measuring the reflectance image with a CCD array detector. Wavelength dependent images are post processed with a multivariate least squares analysis method using known reference spectra of oxy- and deoxyhemoglobin. Alternatively, illuminating with complex reference spectra reduces the number of spectral images required for generating chemically relevant images color encoded for relative percentage of oxyhemoglobin are collected and displayed in real time near-video rate, (3 to 4) frames per second (fps). As a proof of principle application, a kidney of an anesthetized pig was imaged before and after renal vasculature occlusion showing the clamped kidney to be 61% of the unclamped kidney percentage of oxyhemoglobin. Using the "3-Shot" spectral illumination method and gathering data at (3 to 4) fps shows a non-linear exponential de-oxygenation of hemoglobin reaching steady state within 30 seconds post occlusion.

Hyperspectral imaging (HSI), in which each pixel contains a high-resolution spectrum, is a powerful technique that can remotely detect, identify, and quantify a multitude of materials and chemicals. The advent of addressable micro-mirror arrays (MMAs) makes possible a new class of programmable hyperspectral imagers that can perform key spectral processing functions directly in the optical hardware, thus alleviating some of HSI's high computational overhead, as well as offering improved signal-to-noise in certain important regimes (e.g. when using uncooled infrared detectors). We have built and demonstrated a prototype UV-Visible micro-mirror hyperspectral imager that is capable not only of matched-filter imaging, but also of full hyperspectral imagery via the Hadamard transform technique. With this instrument, one can upload a chemical-specific spectral matched filter directly to the MMA, producing an image showing the location of that chemical without further processing. Target chemicals are changeable nearly instantaneously simply by uploading new matched-filter patterns to the MMA. Alternatively, the MMA can implement Hadamard mask functions, yielding a full-spectrum hyperspectral image upon inverting the transform. In either case, the instrument can produce the 2D spatial image either by an internal scan, using the MMA itself, or with a traditional external push-broom scan. The various modes of operation are selectable simply by varying the software driving the MMA. Here the design and performance of the prototype is discussed, along with experimental results confirming the signal-to-noise improvement produced by the Hadamard technique in the noisy-detector regime.

Dispersive transform spectral imagers with both one- and two-dimensional spatial coverage have been demonstrated and characterized for applications in remote sensing, target classification and process monitoring. Programmable spatial light modulators make it possible to adjust spectral, temporal and spatial resolution in real time, as well as implement detection algorithms directly in the digitally controlled sensor hardware. Operating parameters can be optimized in real time, in order to capture changing background and target evolution. Preliminary results are presented for short wave, mid-wave, and long-wave infrared sensors that demonstrate the spatial and spectral versatility and rapid adaptability of this new sensor technology.

A long-standing problem of astrophysical research is how to simultaneously obtain spectra of thousands of sources randomly positioned in the field of view of a telescope. Digital Micromirror Devices, used as optical switches, provide a most powerful solution allowing to design a new generation of instruments with unprecedented capabilities. We illustrate the key factors (opto-mechanical, cryo-thermal, cosmic radiation environment,...) that constrain the design of DMD-based multi-object spectrographs, with particular emphasis on the IR spectroscopic channel onboard the EUCLID mission, currently considered by the European Space Agency for a 2017 launch date.

Current wide area pan-chromatic or dual band persistent surveillance systems often do not provide enough observable data to maintain accurate and unique tracks of multiple objects over a large field of regard. Previous experiments have shown augmentation with hyperspectral imagery can enhance tracking performance. However, hyperspectral imagers have significantly slower coverage rates than persistent surveillance systems, essentially because a hyperspectral pixel contains vector data while a standard image pixel is typically either scalar or RGB. This coverage rate gap is a fundamental mismatch between the two systems and presents a technological hurdle to the practical use of hyperspectral imagers for tracking multiple objects spread over the entire field of regard of persistent surveillance systems. In this non-mapping hyperspectral application, we assume much of the information in a hyperspectral data cube is superfluous background and need not be processed or even collected. The effective coverage rate of the hyperspectral imager can be made compatible with modern persistent surveillance systems, at least for the objects of interest, by using a DMD to judiciously select which data are collected and processed. A proof-of-concept sensor has been developed and preliminary results are presented.

Since the mid-eighties, a fundamental idea for achieving measuring accuracy in projected fringe technology was to consider the projected fringe pattern as an interferogram and evaluate it on the basis of advanced algorithms widely used for phase measuring in real-time interferometry. A fundamental requirement for obtaining a sufficiently high degree of measuring accuracy with this so-called "phase measuring projected fringe technology" is that the projected fringes, analogous to interference fringes, must have a cos²-shaped intensity distribution. Until the mid-nineties, this requirement for the projected fringe pattern measurement technology presented a basic handicap for its wide application in 3D metrology. This situation changed abruptly, when in the nineties Texas Instruments introduced to the market advanced digital light projection on the basis of micro mirror based projection systems, socalled DLP technology, which also facilitated the generation and projection of cos²-shaped intensity and/or fringe patterns. With this DLP technology, which from its original approach was actually oriented towards completely different applications such as multimedia projection, Texas Instruments boosted phase-measuring fringe projection in optical 3D metrology to a worldwide breakthrough both for medical as well as industrial applications. A subject matter of the lecture will be to present the fundamental principles and the resulting advantages of optical 3D metrology based on phase-measuring fringe projection using DLP technology. Further will be presented and discussed applications of the measurement technology in medical engineering and industrial metrology.

We describe our use of Digital Micromirror Devices (DMDs) for the performance testing, characterization, calibration, and system-level data product validation of multispectral and hyperspectral imaging sensors. We have developed a visible Hyperspectral Image Projector (HIP), which is capable of projecting any combination of many different arbitrarily programmable basis spectra into each image pixel at up to video frame rates. For the full HIP, we use a scheme whereby one DMD array is used in a spectrally programmable source, to produce light having the spectra of materials in the scene (i.e. grass, ocean, target, etc), and a second DMD, optically in series with the first, reflects any combination of these programmable spectra into the pixels of a 1024 ×768 element spatial image, thereby producing temporally-integrated 2D images having spectrally-mixed pixels. The HIP goes beyond conventional Digital Light Processing (DLP) projectors in that each spatial pixel can have an arbitrary spectrum, not just an arbitrary color. As such, the resulting spectral and spatial content of the projected image can simulate realistic scenes that a sensor system must acquire during its use, and can be calibrated using NIST reference instruments. Here we discuss our current HIP developments that span the visible/infrared spectral range of 380 nm through 5400 nm, with particular emphasis on DMD diffraction efficiency measurements in the infrared part of this range.

The use of computer generated sinusoidal fringe patterns has found wide acceptance in optical metrology. There are corresponding software solutions that reconstruct the phase field encoded in the fringe pattern in order to get 3D-shape data via triangulation and deflection measuring setups, respectively. Short recording time is a common issue of high importance for all tasks on the factory shop floor as well as in medical applications and for security. Recent high-speed implementations take advantage of MEMS based spatial light modulators and the digital micro mirror chipset DLP Discovery^TM* is the fastest proven component currently available for this aim. Being a bi-stable on-off-state system, the sinusoidal gray level pictures are generated by controlling the mirrors ON-time period during which an analogue detector is exposed. This digital generation of light intensity distributions provides outstanding precision and long-term stability. It is used in leading edge technology solutions that produce video type streams of 3D surface data with a sustained repetition rate of 40 Hz. A new proposal is discussed in this paper that goes beyond this state of the art by considering the optical encoding of the surface as an all-digital communication link. After a brief classification of state-of- the-art systems, the authors describe how future all-digital encoding leads to extremely high speed and precision in 3D shape acquisition.

Compressive imaging (CI) system is a novel electro-optical imaging system design, which uses a single-pixel photo detector to capture two dimensional (2D) images. Instead of sampling the image directly by the sensor following the classic Nyquist-Shannon sampling theorem, CI systems insert a measurement layer between the image formation and the image recording media so that projection measurement matrices used to conduct compressive sampling can be effectively introduced to the imaging process. The Digital Micromirror Device (DMD) can be used to implement the projection measurement matrices. The imaging performance of a DMD based CI system relies more than just on the imaging optics and the pixel size of the sensor. It also depends on the design of the measurement matrices and their physical representations by the DMD. In the present work, we implemented three compressive sampling methods with the DMD, namely the random basis under-sampling method, the random sampling method in the Hadamard space and the variable density sampling method in the Hadamard space. We experimentally demonstrated that the design and implementation of these methods have a direct impact on the imaging performance of the CI system. We tested the system with different sampling ratios, DMD mirror configurations and imaging optics. Their influences on the reconstructed image quality are demonstrated by experimental results. Lastly, we discussed the illumination issue of the reconstructed image, which is not related to resolution, but is important for our visual perception of the reconstructed image.

In this paper, a new approach for Confocal Microscopy (CM) based on the framework of compressive sensing is developed. In the proposed approach, a point illumination and a random set of pinholes are used to eliminate out-of-focus information at the detector. Furthermore, a Digital Micromirror Device (DMD) is used to efficiently scan the 2D or 3D specimen but, unlike the conventional CM that uses CCD detectors, the measured data in the proposed compressive confocal microscopy (CCM) emerge from random sets of pinhole illuminated pixels in the specimen that are linearly combined (projected) and measured by a single photon detector. Compared to conventional CM or programmable array microscopy (PAM), the number of measurements needed for nearly perfect reconstruction in CCM is significantly reduced. Our experimental results are based on a testbed that uses a Texas Instruments DMD (an array of 1024×768; 13.68×13.68 μm² mirrors) for computing the linear projections of illuminated pixels and a single photon detector is used to obtain the compressive sensing measurement. The position of each element in the DMD is defined by the compressed sensing measurement matrices. Threedimensional image reconstruction algorithms are developed that exploit the inter-slice spatial image correlation as well as the correlation between different 2D slices. A comprehensive performance comparison between several binary projection patterns is shown. Experimental and simulation results are provided to illustrate the features of the proposed systems.

The unique qualities of the TI DLP devices have enabled a number of interesting applications. The DLP is essentially a fast binary light modulator and using the power of modern graphics processors these devices can be driven with images computed on the fly at rates of several thousand frames per second. A number of these applications have been developed by the University of Southern California where fast light is exploited to create a light field display. In another application, fast light is coupled with a synchronized high speed camera to extract the 3D shape of an object in real time.

The Micromirror Array Projector System (MAPS) is an advanced dynamic scene projector system developed by Optical Sciences Corporation (OSC) for Hardware-In-the-Loop (HWIL) simulation and sensor test applications. The MAPS is based upon the Texas Instruments Digital Micromirror Device (DMD) which has been modified to project high resolution, realistic imagery suitable for testing sensors and seekers operating in the UV, visible, NIR, and IR wavebands. Since the introduction of the first MAPS in 2001, OSC has continued to improve the technology and develop systems for new projection and Electro-Optical (E-O) test applications. This paper reviews the basic MAPS design and performance capabilities. We also present example projectors and E-O test sets designed and fabricated by OSC in the last 7 years. Finally, current research efforts and new applications of the MAPS technology are discussed.

OPTRA is developing a two-band midwave infrared (MWIR) scene simulator based on digital micromirror device (DMD) technology; this simulator is intended for training various IR tracking systems that exploit the relative intensities of two separate MWIR spectral bands. Our approach employs two DMDs, one for each spectral band, and an efficient optical design which overlays the scenes reflected by each through a common telecentric projector lens. Other key components are a miniature thermal source and a series of dichroic beamsplitters. Through the use of pulse width modulation, we are able to control the relative intensities of objects simulated by the two channels thereby enabling realistic scene simulations of various targets and projectiles approaching the tracking system. Performance projections support radiant intensity levels, resolution, bandwidth, and scene durations that meet the requirements for a host of IR tracking test scenarios. In this paper we summarize the results of a breadboard design, build, and test which establishes the feasibility of our approach. We also present portions of the preliminary design of a prototype two-band simulator which will be built and tested over the next year.

Micro-opto-electro-mechanical-systems (MOEMS) have proven to be a facilitating technology in the lithography industry. Recently, there have been significant advancements in digital micromirror device (DMD) based maskless lithography. These advancements have been in the areas of throughput, resolution, accuracy, and cost reduction. This progression in digital micromirror evolution provides considerable opportunities to displace existing lithographic techniques. Precise control of the individual mircormirrors, including scrolling, and full utilization of the FPGA, have allowed DMD-based lithography systems to reach new levels of throughput and repeatability, while reducing production and warranty costs. Throughput levels have far surpassed scanning laser techniques. Chip level cooling technologies allow for higher incident power to be reliably distributed over larger areas of the substrate. Resolution roadmaps are in place to migrate from the current 2400dpi (11μm) to 4800dpi (5.3μm). Without the constraints of mask requirements, mask alignment, storage, and defect analysis are not required, thus increasing accuracy and reducing cost. This contribution will examine the advancements in and benefits of DMD based maskless lithography.