Imaging Technology

Imaging Technology E-Newsletter - 06/29/09 In this edition, sponsored by Imaging System Identifies Concealed Weapons Using RF Chips 3D Tooth Images Could Replace Plaster Models Prototype Breast Cancer Imaging System May Help Early Diagnosis Coming Attractions: Making the Move to Digital in Machine Vision Imaging System Identifies Concealed Weapons Using RF Chips The UC San Diego RFIC chip could lead to less expensive imagers for detecting concealed weapons. Electrical engineers from the University of California, San Diego are using W-Band silicon-germanium (SiGe) radio frequency integrated circuits (RFICs) for passive millimeter-wave imaging. The resulting imaging systems would identify concealed weapons, help helicopters land during dust storms, and enable high-frequency data communications. The new millimeter-wave amplifier system works at the same frequency and follows the same principles as security imaging systems now in use in airports. The new circuit is unique in that it uses standard silicon semiconductor technology, while today's security imaging systems often rely on expensive gallium arsenide or indium phosphide amplifiers. The circuit includes an antenna that can be used to capture radiation in the millimeter-wave frequency emitted from the human body and from objects under a person's clothing. This radiation passes through clothing largely or completely unaffected. Imagers operating at millimeter waves are particularly useful because they can resolve images down to a millimeter scale, fine enough detail to identify small objects and separate items on a person's body. Using signal processing, these kinds of scanners can put together a temperature map of a person's body that includes any objects underneath the clothing. Click here for the full story. Sponsor Message Falcon 4M60/30 Color DALSA's new Falcon 4M60 and 4M30 cameras offer 4 megapixel resolution with data rates of 60 or 30 fps, and global shuttering for crisp, clear, color imaging. For more information on color imaging, Click here to download our free white paper "When is Color Required for Machine Vision." Click here to learn more about the 4M60 cameras. 3D Tooth Images Could Replace Plaster Models The 3D digitizer produces a 3D "dental snapshot" of the oral cavity. Today, dental technicians can only make dentures using a bite impression. The silicone template for this plaster model is made by the dentist in a procedure that is unpleasant for the patient. Fraunhofer Institute for Applied Optics and Precision Engineering IOF has developed a 3D digitizer to provide the teeth contours without a plaster model. If a dental prosthesis is necessary, the dentist first has to make a silicone impression for the laboratory. The patient is sent home with a provisional repair and dental technicians work on modeling a plaster impression. The model is then scanned using digital cameras and from the geometric measurement data obtained, the matching dental prosthesis is produced. The Fraunhofer team developed an optical digitization system that scans the oral cavity and captures 3D data of the teeth using camera optics. A complete picture of the individual tooth is created from several data records. After an all-around measurement, it is possible to represent the complete jaw arch as a virtual computer image. To obtain precise results, the team used fringe projections in which a projector shines strips of light on the tooth area to be measured. From the phase-shifted images, the evaluation software determines the geometric contour data of the tooth. Two-camera optics provide the sensor chip with image information from different measurement perspectives. After the pixel-precise comparison of various camera images, the evaluation program recognizes any image faults and removes them from the complete image. It is problematic if the patient moves while the images are being taken in the oral cavity, so the image sequence for each measurement position is captured in less than 200 milliseconds. Click here for the full story. SPONSOR MESSAGE Piranha HS 110 kHz Piranha HS features 4k resolution with 14x14 micron pixels and an incredible 110 kHz line rate with throughput of 640 MPixels/s. Featuring proprietary TDI technology, the Piranha HS delivers responsivity of 11,800DN/njcm2 at 0dB 12 bit with 100x anti-blooming capability. TDI (Time Delay and Integration) is a method of line scan which provides dramatically increased responsivity compared to other video scanning methods. Click here to download our free white paper "How TDI Line Scan Works." Prototype Breast Cancer Imaging System May Help Early Diagnosis This close-up of the PET part of the breast imaging system shows the individual detector units. Researchers with Brookhaven National Laboratory and Stony Brook University have developed a prototype breast imaging system combining positron emission tomography (PET) and magnetic resonance imaging (MRI) technologies. Although the system has not yet been tested on humans, initial results from the prototype indicate the system produces a fusion of detailed PET and MRI images that should allow a more accurate classification of lesions in the breast. Every year, approximately 180,000 women are newly diagnosed with breast cancer. While the disease is still a leading cause of death among women, breast cancer mortality is declining. In particular, new developments in molecular imaging technologies are dramatically improving the ways in which breast cancer is diagnosed and treated. However, many challenges remain in breast imaging, such as obtaining accurate images of dense breast tissue. When completed, the dedicated breast PET-MRI system will consist of a modular 3D tomographic PET scanner that is inserted inside a dedicated breast MRI coil produced by Aurora Technologies. The modularity of the PET system would allow for the scanner diameter to be adjusted according to patient breast size. Researchers expect the combined modality scanner will provide anatomical information from the MRI to enhance the resolution provided by PET. At the same time, the predictive power of PET in identifying the type of tumor should be able to overcome MRI technology's traditionally high false-positive rates. Click here for the full story. Machine Vision Guides Robot Motion Machine vision can quickly and accurately determine the location of parts so they can be inspected, measured, or manipulated by a robot. A machine vision system works best with an undistorted view of properly lighted and well-controlled parts. The first tasks in developing a machine vision application are to fix the view geometry, control the lighting, and limit the variation of the presented parts. An example is using machine vision to guide a robot unpacking one-gallon cans from a large pallet of cans. Machine vision components - cameras, vision processors, and software - were provided by DALSA, and Faber Industrial Technologies developed the can-picking robot and integrated the robot with the machine vision. A feature in the June issue of Imaging Technology by Ben Dawson of DALSA describes how machine vision and robotics were combined to achieve a safe, time-saving system.' Click here for the full story.