Abstract: An in-vivo device, system and a method for imaging a body lumen, typically liquid filled body lumen. The in-vivo device may have a specific gravity of about 1 or a volume to weight ratio that enables it to float. The in-vivo device may include an optical system for viewing through a body lumen liquid and another optical system for viewing through a non liquid medium. The in-vivo device may be moved through the body lumen by the liquid movement in that lumen.

Abstract: The present invention provides an in-vivo imaging device comprising at least one imager and an associated optical system, at least the optical system located in an optical dome of the imaging device, the optical dome having a tip, the optical system comprising an optical lens, the optical system having a given effective focal length f, the optical lens being located at a distance D? from the tip; wherein D?/f?6.

Abstract: An for example autonomous in vivo sensing device may include a polarizing filter to polarize light emitted by an illumination unit, and to block light specularly reflected from a turbid media from reaching an imager of such device A for example autonomous in vivo sensing device with monochromatic illumination units to alternatingly illuminate a target area with light of different wavelengths, and to subtract an image illuminated by light in a first wavelength from an image illuminated by light in a second wavelength, to produce an image of a sub-surface layer of such target area.