An ingestible capsule for in vivo imaging and/or treatment of one or more diseased tissue areas of interest within the gastrointestinal tract of an animal or human being, said capsule comprising: an image sensor; a lens system for focusing images of interest onto the image sensor; at least one light source (36, 38) for providing illumination to the tissue of the gastrointestinal tract and is optionally capable of providing optical therapeutic treatment to the diseased tissue areas; a variable lens system located in front of the at least one light source (36, 38), wherein the variable lens system comprises beam steering means and focusing means for directing and focusing the light beams from the at least one light source (36, 38) onto the diseased tissue areas; a control unit in communication with the image sensor, the at least one light source (36, 38), and the variable lens system, the control unit comprising image storing means, processing means and image transmission means; a power source for powering the image sensor, the at least one light source (36, 38) and the control unit; and a non-digestible, transparent outer protective shell configured to pass through the gastrointestinal tract, housing within the image sensor, the lens system, the at least one light source (36, 38), the variable lens system, the control unit and the power source characterized in that the control unit is configured to identify the diseased tissue area in an image of interest received from the image sensor, to correlate the diseased tissue area as the capsule travels through the gastrointestinal tract with an image of light beams from the at least one light source (36, 38) received from the image sensor and to control the beam steering means and focusing means of the variable lens system to ensure that the light beams from the at least one light source (36, 38) are directed and focused onto the diseased tissue areas. an image sensor; a lens system for focusing images of interest onto the image sensor; at least one light source (36, 38) for providing illumination to the tissue of the gastrointestinal tract and is optionally capable of providing optical therapeutic treatment to the diseased tissue areas; a variable lens system located in front of the at least one light source (36, 38), wherein the variable lens system comprises beam steering means and focusing means for directing and focusing the light beams from the at least one light source (36, 38) onto the diseased tissue areas; a control unit in communication with the image sensor, the at least one light source (36, 38), and the variable lens system, the control unit comprising image storing means, processing means and image transmission means; a power source for powering the image sensor, the at least one light source (36, 38) and the control unit; and a non-digestible, transparent outer protective shell configured to pass through the gastrointestinal tract, housing within the image sensor, the lens system, the at least one light source (36, 38), the variable lens system, the control unit and the power source characterized in that the control unit is configured to identify the diseased tissue area in an image of interest received from the image sensor, to correlate the diseased tissue area as the capsule travels through the gastrointestinal tract with an image of light beams from the at least one light source (36, 38) received from the image sensor and to control the beam steering means and focusing means of the variable lens system to ensure that the light beams from the at least one light source (36, 38) are directed and focused onto the diseased tissue areas.