Switchable window element having a dark state and a bright state and a layer structure comprising a switchable layer , two polarizers and two optical retarders, wherein a first polarizer and a first optical retarder are arranged in an optical path prior to the switchable layer and a second polarizer and a second optical retarder are arranged in the optical path after the switchable layer , wherein the switchable layer is a vertically aligned liquid crystal layer comprising a liquid crystalline medium, wherein the product of the thickness d of the switchable layer and the optical anisotropy Δn of the liquid crystalline medium is in the range of from 0.05 μm to 3.0 μm and the liquid crystalline medium has a clearing point of at least 70°C, wherein the layer structure comprises in this order a first polarizer layer as first polarizer, a first retardation element as first optical retarder, a first electrode layer , a first alignment layer , the switchable layer , a second alignment layer , a second electrode layer , a second retardation element as second optical retarder, and a second polarizer layer as second polarizer, wherein the first retardation element and the second retardation element are layer structures comprising an optically isotropic substrate and a retardation layer . wherein the switchable window comprises at least one further substrate and at least one interlayer , wherein the at least one further substrate is connected to the first polarizer layer and/or second polarizer layer by means of the at least one interlayer , wherein in the dark state the transmission of visible light through the switchable window element is less than 2%, wherein the transmission of visible light is measured in accordance with EN 410:2011-04, and wherein the switchable window element is curved in space along two directions. wherein the switchable layer is a vertically aligned liquid crystal layer comprising a liquid crystalline medium, wherein the product of the thickness d of the switchable layer and the optical anisotropy Δn of the liquid crystalline medium is in the range of from 0.05 μm to 3.0 μm and the liquid crystalline medium has a clearing point of at least 70°C, wherein the layer structure comprises in this order a first polarizer layer as first polarizer, a first retardation element as first optical retarder, a first electrode layer , a first alignment layer , the switchable layer , a second alignment layer , a second electrode layer , a second retardation element as second optical retarder, and a second polarizer layer as second polarizer, wherein the first retardation element and the second retardation element are layer structures comprising an optically isotropic substrate and a retardation layer . wherein the switchable window comprises at least one further substrate and at least one interlayer , wherein the at least one further substrate is connected to the first polarizer layer and/or second polarizer layer by means of the at least one interlayer , wherein in the dark state the transmission of visible light through the switchable window element is less than 2%, wherein the transmission of visible light is measured in accordance with EN 410:2011-04, and wherein the switchable window element is curved in space along two directions. <EOS>