Arrangement for changing the visual appearance of a target object

An arrangement comprising a lighting system and a target object, the lighting system being arranged to illuminate a target surface of the target object with a primary light output having a primary illumination spectrum representing a first color, and with a secondary light output having a secondary illumination spectrum representing a second color, wherein the primary and secondary illumination spectra have different spectral power distributions, and wherein the first and second colors have a color difference that is equal to or lower than a predetermined threshold (ΔET) that is the lower of 20 and the outcome of the following equation:

• ΔET=ΔE0+αΔt
• wherein ΔE0 is equal to 8, α is equal to 8 per second, and Δt represents the shortest time it takes the illumination of an arbitrary area on the target surface to change between the primary light output and the secondary light output, and
• the target surface comprising a first target surface area and a second target surface area, wherein upon illumination with the primary illumination spectrum, the first target surface area has a primary first color and the second target surface area has a primary second color, and the first and second target surface areas have a first contrast, and upon illumination with the secondary illumination spectrum, the first target surface area has a secondary first color and the second target surface area has a secondary second color, and the first and second target surface areas have a second contrast, the second contrast being larger than the first contrast, and the term “contrast” referring to the color difference of the first and second target surface areas, and for two colors in CIE 1967 (L*a*b*) color space, the color difference is given by
• ΔE=√{square root over ((L2*−L1*)2+(a2*−a1*)2+(b2*−b1*)2)} (2)
• where L1* and L2* respectively refer to lightness of the two colors, a1* and b1* relate to chromaticity of one color, a2* and b2* relate to chromaticity of the other color.