Device for modifying light distribution

An illuminator system comprising:

• at least one light source, and
• at least one device for modifying distribution of light emitted by the at least one light source,
• the device comprising a transparent body made of transparent material having refractive index greater than one, and the transparent body comprising a first surface, a second surface on an opposite side of the transparent body with respect to the first surface, and at least one third surface joining the first surface, wherein:
• the second surface defines a cavity opening away from the first surface,
• the second surface is configured to reflect, towards the third surface, at least a part of the light received via the first surface,
• the third surface is configured to reflect, towards the second surface, the light reflected from the second surface, and
• the second surface is configured to act as a light egress surface for the light reflected from the third surface,
• wherein the third surface comprises at least one groove on a propagation path of a part of the light reflected from the second surface so that the part of the light reflected from the second surface propagates across the groove prior to being reflected from the third surface.