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Publications (6)3.39 Total impact

  • Andrew L. Dlugan, Calum E. MacAulay
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    ABSTRACT: Conventional endoscopy is limited to imaging macroscopic views of tissue. The British Columbia Cancer Research Center, in collaboration with Digital Optical Imaging Corp., is developing a fiber-bundle based microendoscopy system to enable in vivo confocal imaging of cells and tissue structure through the biopsy channel of an endoscope, hypodermic needle, or catheter. The feasibility of imaging individual cells and tissue architecture will be presented using both reflectance and tissue auto-fluorescence modes of imaging. The system consists of a coherent fiber bundle, low-magnification high-NA objective lens, Digital Micromirror DeviceTM(DMD), light source, and CCD camera. The novel approach is the precise control and manipulation of light flow into and out of individual optical fibers. This control is achieved by employing a DMD to illuminate and detect light from selected fibers such that only the core of each fiber is illuminated or detected. The objective of the research is to develop a low-cost, clinically viable microendoscopy system for a range of detection, diagnostic, localization and differentiation uses associated with cancer and pre-cancerous conditions. Currently, multi-wavelength reflectance confocal images with 1 micrometers lateral resolution and 1.6 micrometers axial resolution have been achieved using a 0.95 mm bundle with 30,000 fibers.
    Proc SPIE 01/2001;
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    ABSTRACT: We present a novel fiber-optic confocal microscope in which the scanning operation is achieved by use of a spatial light modulator (SLM) to sequentially illuminate individual fibers or patterns of multiple fibers. Experimental images are presented, and the optical-sectioning capability of the device is demonstrated. The novel SLM-based system is more optically efficient, achieves higher contrast, and has improved optical-sectioning capabilities compared with those of other proposed instruments for confocal microendoscopy.
    Optics Letters 01/2001; 25(24):1780-2. · 3.39 Impact Factor
  • Calum MacAulay, Andrew Dlugan, Pierre Lane
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    ABSTRACT: © 2000 Optical Society of America
    04/2000;
  • Andrew L. Dlugan, Calum E. MacAulay
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    ABSTRACT: All of the different modes of microscopy deliver light in a controlled fashion to the object to be examined and collect as much of the light containing the desired information about the object as possible. The system being presented replaces the simple circular or annular diaphragms of a conventional microscope with digital micromirror devices to enable digital light microscopy. The DMDs are placed in the optical path at positions corresponding to the field and aperture diaphragms of a conventional microscope. This allows for more precise and flexible control over the spatial location, amount, and angles of the illumination light, and the light to be collected. Digital light microscopy enables the improvement of existing modes of microscopy, specifically for quantitative microscopy applications. Confocal microscopy has been performed, realizing improvements in resolution, flexibility, and cost. Three different combinations of image acquisition and post- processing algorithms have ben sued to generate confocal images, as well as a tomographic reconstruction image.
    Proc SPIE 01/2000;
  • Andrew L. Dlugan, Calum E. Macaulay
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    ABSTRACT: There are many different modes of microscopy, and all of these modes deliver light in a controlled fashion to the object to be examined and collect as much of the light containing the desired information about the object as possible. The system being presented replaces the simple irises of a conventional microscope with digital micromirror devices (DMDs, made by Texas Instruments) to produce a digital microscope. The DMDs are placed in the optical path at positions corresponding to the field and aperture diaphragms of a conventional microscope. This allows for more precise and flexible control over the spatial location, amount, and angles of the illumination light, and the light to be collected. This digital microscope will improve existing modes of microscopy, specifically in quantitative microscopy. Using the intensity modulation feature of the DMDs, the system can correct for inhomogeneous illumination sources to achieve uniform distributions. In various configurations, one can perform brightfield, darkfield, confocal and fluorescence microscopy. In addition, new microscopy modes will be possible, such as reconstruction microscopy. Utilizing the fast switching times of the mirrors (under 20 microseconds), one can switch between modes efficiently.
    Proc SPIE 06/1999;
  • Calum E. Macaulay, Andrew Dlugan
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    ABSTRACT: There are numerous modes of microscopy such as brightfield, darkfield, phase contrast, fluorescence, reflected light, confocal, etc. All of these forms of microscopy deliver illumination light in a controlled fashion to the object to be examined and collect as much light containing the desired information as possible. The majority of these methods use appropriately placed and formed diaphragms (iris, pin hole, annulus, etc.) and lenses to control both the incident angles of the illumination light and its intensity as well as the size and location of the illuminated area in the sample. Usually these diaphragms are a simple iris or annulus and are almost always static. The novel aspect of the system being presented is to replace these simple mechanical diaphragms with digital micro mirror devices (1DMDs made by Texas Instruments) to allow for more precise, flexible control over the transmission behavior of these optical planes. By placing DMDs in the same plane (actual or conjugate) as that of the field iris, illumination aperture iris (condenser diaphragm), objective lens aperture stop, and field stop, one has the ability to rapidly switch between brightfield, darkfield, confocal and reconstruction microscopy. In addition because of the intensity modulating features of DMDs, one can create a uniform illumination distributions in the sample or a non- uniform distribution.
    Proc SPIE 04/1998;