摘要 |
An endoscope objective lens for collecting combined bright field (white light) and fluorescence images includes a negative lens group, a stop, and a positive lens group. The lens has a combination of large entrance pupil diameter (≧0.4 mm) for efficiently collecting weak fluorescence light, large ratio between the entrance pupil diameter and the maximum outside diameter (Dentrance/Dmax larger than 0.2), large field of view (FFOV≧120°) and favorably corrected spherical, lateral chromatic and Petzval field curvature for both visible and near infrared wavelengths.
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