A colposcope is a stereoscopic binocular microscope which enables the illumination and observation of the uterine cervix under low magnification (between 4× and 6×) 35. The colposcope used in this study, shown in Fig. 1(a), is an Olympus OSC 500 and is one of the most commonly used for colposcopy. The light is delivered by a 150?W halogen lamp source (Olympus CLH-SC), and is usually guided by a silica fiber bundle to the colposcope. In order to increase the amount of light incident on the uterine cervix under analysis, a liquid light guide (Thorlabs LLG0538-6) has been used instead of the fiber bundle due to its better transmission performances in the visible spectral range (340?nm–800?nm). In the classical colposcope design, a lens collimates the LED Flood Light exiting the flexible light guide. The position of the end of the light guide has been optimized and placed near the focal plane of this lens in order to reduce the spot size of the beam from 15?cm to 6?cm at working distance of 30?cm. This working distance is the typically mean distance between the colposcope and the uterine cervix under real-world conditions.
Figure 1
Figure 1

(a) Photo of the entire MPC system (1: Polarimetric head, 2: Binoculars for stereoscopic vision of the uterine cervix, 3: Liquid LED Flood Light guide, 4: CCD camera). The polarimetric head is in the “OFF” position, and permit classical colposcopic observations. (b) Polarimetric system can be slid on the “ON” position to permit the acquisition of Mueller polarimetric images (5: Polarization States Generator (PSG), 6: Polarization States Analyzer (PSA)).
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In order to perform measurements