![]() Alternatively, images can be generated over a large FOV using a much simpler strategy by deflecting a low numerical aperture (NA) collimated beam at wide angles. The pixel number in the sensor is typically much greater than the number of fibers in a flexible optical bundle. Achromats are used to correct for chromatic dispersion so that light over the visible spectrum (400–700 nm) can focus on a detector. ![]() Barrel distortion is introduced by increasing the magnification in the center versus that in the periphery to achieve a maximum divergence angle up to 140° (± 70°) or more. The rigid distal tip of conventional medical endoscopes contains a complex arrangement of objective lenses to achieve high spatial resolution with a large image field-of-view (FOV) 6. A flexible, fiber-coupled accessory can pass through this channel if the dimensions are sufficiently small. Medical endoscopes have working channels that are typically several millimeters in diameter, and can pass instruments for tissue resection 4, 5, 6. A number of fluorophores, such as fluorescein and indocyanine green (ICG), are FDA-approved for clinical administration, and can be used to label ligands that bind specifically to biomarkers of disease 13. The optical spectrum provides a wide range of wavelengths (500–900 nm) that can be separated into different channels used to perform multiplexed detection of unique molecular targets 10, 11, 12. Fluorescence can be used to label ligands, such as peptides, and provide high contrast to distinguish regions of pathology from surrounding areas of normal tissues. ![]() White light illumination is currently used to identify pre-malignant masses, such as polyps, but has limited effectiveness to identify lesions that are flat and subtle in appearance 7, 8, 9. Images can be collected in vivo in real time with high spatial resolution to identify and localize abnormal regions. Endoscopes can be inserted into natural body orifices to access this highly metabolically active layer of tissue that serves as the origin of many human disorders 4, 5, 6. Improved methods are needed to detect diseases that originate from the mucosal surface of hollow organs, such as colon 1, 2, 3. This instrument demonstrates potential for broad clinical use to detect heterogeneous diseases in hollow organs. Target-to-background ratios of 2.6, 3.1, and 3.9 were measured. The fluorescence images collected were separated into 3 channels. Multiplexed fluorescence images were collected in vivo from the rectum of live mice using 3 fluorescently-labeled peptides that bind to unique cell surface targets. Maximum total divergence angles of ± 27.4° and ± 22.8° were generated to achieve a FOV of 10.4 and 8.4 mm, respectively, at a working distance of 10 mm. The scan mirror was driven at 27.6 and 9.04 kHz in the fast (X) and slow (Y) axes, respectively, using a square wave with 50% duty cycle at 60 V pp to collect fluorescence images at 10 frames per sec. The optomechanical components were packaged in a rigid distal tip with dimensions of 2.6 mm diameter and 12 mm length. A large image field-of-view (FOV) was generated in real time. The mirror was driven at resonance for wide angular deflections in the X and Y-axes. A miniature scan mirror with reflector dimensions of 1.30 × 0.45 mm 2 was designed, fabricated, and placed distal to collimated excitation beams at λ ex = 488, 660, and 785 nm. We aim to demonstrate a flexible fiber-coupled accessory that can pass forward through the instrument channel of standard medical endoscopes for clinical use to collect fluorescence images. Trail off the sharp light to make the light more soft and reduce the light and shade contrast.A wide-field endoscope that is sensitive to fluorescence can be used as an adjunct to conventional white light endoscopy by detecting multiple molecular targets concurrently. Provide light to reduce shadow.įor "Shoot Through" position photograph. ![]() Highlight the fine surface texture and improves color saturation. Make soft warm tone, decrease the exposal from background to foreground, More natural effect when back lighting.
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