Optical device

A lighting apparatus comprising a light source system and an optical device being made of transparent material and comprising:

• a front wall constituting a front portion,
• a coupling portion configured to mechanically connect to the light source system, and
• side walls between the coupling portion and the front portion,
• wherein the front wall is configured to let through a first part of light emitted by the light source system and the side walls are configured to let through a second part of the light, and surfaces of the side walls are shaped to have grooves to refract at least 80% of the second part of the light obliquely rearwards with respect to a first direction from a geometric center point of the coupling portion to a geometric center point of the front portion, and wherein each of the grooves has a first side and a second side, the second side being angled with respect to the first direction so that an angle between a geometric normal of the second side and the first direction is greater in a first one of the grooves that is closer to the coupling portion than in a second one of the grooves that is closer to the front portion, the light source system comprising a light source and being positioned at the coupling portion of the optical device.

A lighting system comprising a floor and a ceiling to be illuminated and at least one lighting apparatus between the floor and the ceiling, the lighting apparatus comprising a light source system and an optical device being made of transparent material and comprising:

• a front wall constituting a front portion,
• a coupling portion configured to mechanically connect to the light source system, and
• side walls between the coupling portion and the front portion,
• wherein the front wall is configured to let through a first part of light emitted by the light source system and the side walls are configured to let through a second part of the light, and surfaces of the side walls are shaped to have grooves to refract at least 80% of the second part of the light obliquely rearwards with respect to a first direction from a geometric center point of the coupling portion to a geometric center point of the front portion, and wherein each of the grooves has a first side and a second side, the second side being angled with respect to the first direction so that an angle between a geometric normal of the second side and the first direction is greater in a first one of the grooves that is closer to the coupling portion than in a second one of the grooves that is closer to the front portion, the light source system comprising a light source and being positioned at the coupling portion of the optical device, wherein the front wall of the optical device of the lighting apparatus is directed towards the floor.