A projector of light beams comprising at least: - a shell having a first end and a second end joined by a central frame to define an axis of extension of the shell; - a light source located at the first end of the shell and connected to a source of energy for emitting a light beam along a lighting trajectory parallel to the axis of extension of the shell; - an outlet lens of the light beam positioned at the second end of the shell; - a first optical body for focusing the light beam, interposed between the light source and the outlet lens, and connected internally to the frame; the first optical body being configured to move in both directions along the frame in such a way as to modify its distance from the light source along a trajectory parallel to the axis of the shell; - a second optical body for varying the focal length of the light beam, interposed between the first optical body and the outlet lens and connected internally to the frame; the second optical body being configured to move in both directions along the frame for modifying its position relative to the outlet lens and to the first optical body along a trajectory parallel to the axis of the shell; - at least a third optical body generating an optical effect acting on the beam of light and positioned inside the frame; the third optical body having means for supporting a lens for optical effect configured for moving, between a non-operating position, wherein the third optical body is moved away from the light beam, and an operating position, wherein the third optical body is positioned along the trajectory of illumination of the light beam; the projector of light beams being characterised in that it comprises: - a carriage for supporting the third optical body connected to a wall of the frame; - movement means positioned on the frame and connected to the carriage for moving, in both directions, the at least third optical body along a trajectory parallel to the axis of the shell in such a way as to modify its position relative to the first and to the second optical body; and wherein the frame comprises a first wall for connecting to the carriage having two openings (16, 17) separated by a central column on which is positioned a guide for sliding of the carriage; the carriage comprising a plate equipped with a slide for coupling with the guide and configured to enclose the central column of the frame. - a shell having a first end and a second end joined by a central frame to define an axis of extension of the shell; - a light source located at the first end of the shell and connected to a source of energy for emitting a light beam along a lighting trajectory parallel to the axis of extension of the shell; - an outlet lens of the light beam positioned at the second end of the shell; - a first optical body for focusing the light beam, interposed between the light source and the outlet lens, and connected internally to the frame; the first optical body being configured to move in both directions along the frame in such a way as to modify its distance from the light source along a trajectory parallel to the axis of the shell; - a second optical body for varying the focal length of the light beam, interposed between the first optical body and the outlet lens and connected internally to the frame; the second optical body being configured to move in both directions along the frame for modifying its position relative to the outlet lens and to the first optical body along a trajectory parallel to the axis of the shell; - at least a third optical body generating an optical effect acting on the beam of light and positioned inside the frame; the third optical body having means for supporting a lens for optical effect configured for moving, between a non-operating position, wherein the third optical body is moved away from the light beam, and an operating position, wherein the third optical body is positioned along the trajectory of illumination of the light beam; the projector of light beams being characterised in that it comprises: - a carriage for supporting the third optical body connected to a wall of the frame; - movement means positioned on the frame and connected to the carriage for moving, in both directions, the at least third optical body along a trajectory parallel to the axis of the shell in such a way as to modify its position relative to the first and to the second optical body; and wherein the frame comprises a first wall for connecting to the carriage having two openings (16, 17) separated by a central column on which is positioned a guide for sliding of the carriage; the carriage comprising a plate equipped with a slide for coupling with the guide and configured to enclose the central column of the frame. - a carriage for supporting the third optical body connected to a wall of the frame; - movement means positioned on the frame and connected to the carriage for moving, in both directions, the at least third optical body along a trajectory parallel to the axis of the shell in such a way as to modify its position relative to the first and to the second optical body; and wherein the frame comprises a first wall for connecting to the carriage having two openings (16, 17) separated by a central column on which is positioned a guide for sliding of the carriage; the carriage comprising a plate equipped with a slide for coupling with the guide and configured to enclose the central column of the frame.