What is wall graze lighting and why do we need it ?

WALL GRAZE LIGHTING
Wall grazing or vertical surface highlight is used only whenthere is a need to illuminate a special architecture surfacto make it radiate with light. This is specially useful when weneed to highlight texture, material, or any other kind ofmaterial.
This kind of lighting is challenging because specialised opticsdelivering a punch of light are not commonly found. But withlinear profiles using LED sources, t is possible to create thiseffect in a very slim form factor.
This is a big development over traditional light sources thatwere circular in nature, because traditional light sourcetneeded to be many and placed closed to each other to getoverlapping light beams, whereas this is not the case withlinear light fixtures that are joined end to end.
Which parameters have to be carefully evaluated?
· Reflection from wall surface
· Coverage of light - no shadow spots
· Extent of spill light(to the floor surface)
· Integration into architectural ceiling design
· Low glare
What is the IK protection level test ?