An imaging apparatus, comprising: a retractable structure comprising: a retractable first lens group on an optical axis, a lens group actuator configured to move the retractable first lens group along the optical axis, and an optical image stabilizer configured to move the retractable first lens group together with the lens group actuator along the optical axis between a first position and a second position; an image sensor on the optical axis; and a second lens group comprising at least one lens immovably connected to the image sensor by gluing directly to the image sensor or by attachment with mechanical elements on two or more edges of the image sensor; wherein: in the first position the retractable first lens group and the lens group actuator reside at a distance from the second lens group and the image sensor, in the second position the retractable first lens group and the lens group actuator reside at another distance from the second lens group, and the second lens group comprises a field flattening lens having a concave shaped surface on a side opposite to the image sensor, characterized in that the imaging apparatus further comprises a lifting mechanism configured to alter the distance between the retractable first lens group and the image sensor by moving the retractable structure. a retractable structure comprising: a retractable first lens group on an optical axis, a lens group actuator configured to move the retractable first lens group along the optical axis, and an optical image stabilizer configured to move the retractable first lens group together with the lens group actuator along the optical axis between a first position and a second position; an image sensor on the optical axis; and a second lens group comprising at least one lens immovably connected to the image sensor by gluing directly to the image sensor or by attachment with mechanical elements on two or more edges of the image sensor; wherein: in the first position the retractable first lens group and the lens group actuator reside at a distance from the second lens group and the image sensor, in the second position the retractable first lens group and the lens group actuator reside at another distance from the second lens group, and the second lens group comprises a field flattening lens having a concave shaped surface on a side opposite to the image sensor, characterized in that the imaging apparatus further comprises a lifting mechanism configured to alter the distance between the retractable first lens group and the image sensor by moving the retractable structure. in the first position the retractable first lens group and the lens group actuator reside at a distance from the second lens group and the image sensor, in the second position the retractable first lens group and the lens group actuator reside at another distance from the second lens group, and the second lens group comprises a field flattening lens having a concave shaped surface on a side opposite to the image sensor, characterized in that the imaging apparatus further comprises a lifting mechanism configured to alter the distance between the retractable first lens group and the image sensor by moving the retractable structure.