Experimental aspects of halographic interferometry

Q-switched ruby laser holography with optical equipment to compensate for spatial and temporal incoherence for contouring, aerodynamic visualization, and nondestructive testin

Increased image resolution and film efficiency via vacuum platens and other mechanical devices

With an appropriate lens, focusing arrangement, film and processing, motor driven 35mm cameras will attain resolutions of hundreds of line pairs per millimeter. The combination of a narrow depth of focus, unusually thin films, a relatively large film gate and rapidly advancing films can produce imagery with less than optimum resolution across or within individual frames. A vacuum platen and an additional styrene pressure plate were fitted to a motorized 35mm camera in an effort to insure the film lies flat. Continuous vacuum pulling mechanisms, suction and induction, were evaluated. Each system\u27s simplicity, portability and statistically analyzed imagery were assessed. Test imagery indicated a ten percent increase of in focus image area for the vacuum platen and a fifty-five percent increase for the styrene pressure plate. Several suitable vacuum pulling mechanisms were found. Overall, the inexpensive, simply constructed and easily installed styrene pressure plate is recommended for any high resolution, small format camera system

Robotic large-area optical biopsy imaging for automated detection of gastrointestinal cancers tested in tissue phantoms and ex vivo porcine bowel

Gastrointestinal endoscopy is a subjective procedure that frequently requires tissue samples for diagnosis. Contact optical biopsy (OB) techniques have the aim of providing direct diagnosis of endoscopic areas without excising tissue samples but lack the wide-area coverage required for locating and resecting lesions. This article presents a large-area robotically deployed OB imaging platform for endoscopic detection of colorectal cancer as an add-on for conventional endoscopes. In vitro, in silicon colon phantoms, the platform achieves an optical resolution of 0.5 line pairs per millimeter, while resolving simulated cancer lesions down to 0.75 mm diameter across large-area images (55-103 cm2). Large-area OB images were generated in an ex vivo porcine colon. The platform allows centimeter-sized large-area OB imaging in vitro and ex vivo with submillimeter resolution, including automatic data segmentation of simulated cancer areas. The ability for robotic actuation and spectrum collection is also shown for ex vivo animal colon. If successful, this technology could widen access to user-independent high-quality endoscopy and early detection of gastrointestinal cancers

Maxillo: Facial diagnosis

The application of the Lixiscope in dentistry was studied. Due to a problem in resolution, it is concluded that, at this present time, the Lixiscope can only be as a previewing device for conventional radiography

Evaluation of film type QX 807 (SO-368, Kodak Ektachrome MS, Estar thin base, with an equivalent Wratten 2A filter overcoat)

A color film with a sensitivity and color balance equal to SO-368, Kodak MS Ektachrome (Estar thin base) was required for use on the Apollo-Soyuz test project (ASTP). A Wratten 2A filter was required for use with the film to reduce short wavelength effects which frequently produce a blue color balance in aerial photographs. The background regarding a special emulsion which was produced with a 2A filter equivalent as an integral part of an SO-368 film manufactured by Eastman Kodak, the cost for production of the special film, and the results of a series of tests made within PTD to certify the film for ASTP use are documented. The tests conducted and documented were physical inspection, process compatibility, effective sensitivity, color balance, cross section analysis, resolution, spectral sensitivity, consistency of results, and picture sample analysis

A microprocessor-based one dimensional optical data processor for spatial frequency analysis

A high degree of accuracy was obtained in measuring the spatial frequency spectrum of known samples using an optical data processor based on a microprocessor, which reliably collected intensity versus angle data. Stray light control, system alignment, and angle measurement problems were addressed and solved. The capabilities of the instrument were extended by the addition of appropriate optics to allow the use of different wavelengths of laser radiation and by increasing the travel limits of the rotating arm to + or - 160 degrees. The acquisition, storage, and plotting of data by the computer permits the researcher a free hand in data manipulation such as subtracting background scattering from a diffraction pattern. Tests conducted to verify the operation of the processor using a 25 mm diameter pinhole, a 39.37 line pairs per mm series of multiple slits, and a microscope slide coated with 1.091 mm diameter polystyrene latex spheres are described