Confocal point-scanning microscopy has been showing promise in the detection, diagnosing and mapping of skin lesions
in clinical settings. The noninvasive technique allows provides optical sectioning and cellular resolution for in vivo
diagnosis of melanoma and basal cell carcinoma and pre-operative and intra-operative mapping of margins. The imaging
has also enabled more accurate "guided" biopsies while minimizing the otherwise large number of "blind" biopsies.
Despite these translational advances, however, point-scanning technology remains relatively complex and expensive.
Line-scanning technology may offer an alternative approach to accelerate translation to the clinic. Line-scanning, using
fewer optical components, inexpensive linear-array detectors and custom electronics, may enable smaller, simpler and
lower-cost confocal microscopes. A line is formed using a cylindrical lens and scanned through the back focal plane of
the objective with a galvanometric scanner. A linear CCD is used for detection. Two pupil configurations were
compared for performance in imaging human tissue. In the full-pupil configuration, illumination and detection is made
through the full objective pupil. In the divided pupil approach, half the pupil is illuminated and the other half is used for
detection. The divided pupil configuration loses spatial and axial resolution due to a diminished NA, but the sectioning
capability and rejection of background is improved. Imaging in skin and oral mucosa illustrate the performance of the
two configurations.
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