43‐3: Distinquished Paper: Brilliant Cosmetic Film for Ambient Displays, with Cholesteric Liquid Crystal

Abstract

A brilliant cosmetic film with polymerized cholesteric material (PCM) has been developed. The film features a variety of colors by helical pitch gradients, diffusive texture, and arbitrary color patterns. It hides the display when turned off, and transmits display images when turned on. We believe it could change the display in the Off‐state from the conventional black wall to specially designed decorations. In addition, they can be applied to hidden sensors.

Novel cholesteric liquid crystal films creating angle insensitive reflective colors

“…By controlling this pitch, various colors can be expressed 2 . As shown in Figure 1, our Ch‐LC films show the remarkable property of patterning colors by changing the helical pitch in the plane direction 3,4 …”

“…In our previous study, we have found that Ch-LC can be given slightly wavy alignment by controlling the surface energy of the substrate. 3 As shown in Figure 4, since the wavy alignment reflects the light from various directions to one specific direction and the waveform is broadened, the color change of the reflection with change in viewing angle is reduced. 9 However, the average tilt angle of Ch-LC films was low (i.e., 4 ), and the reduction of color change was insufficient.…”

“…In the OFF‐state, since the external light reflects from the Ch‐LC layer of the film, the decoration pattern is visible. On the other hand, in the ON‐state, linearly polarized light emitted from the display is converted into light that is circularly polarized in the opposite direction of the helix of the Ch‐LC layer by a quarter wavelength plate (QWP), 5,6 and the light from the display can transmit through the film without loss 3 . In addition, unlike metal decoration films, Ch‐LC films transmit radio waves.…”

“…2 As shown in Figure 1, our Ch-LC films show the remarkable property of patterning colors by changing the helical pitch in the plane direction. 3,4 Ch-LCs also have the characteristics that they reflect circularly polarized light of the same sense as the helix of the Ch-LCs and transmit circularly polarized light of the opposite sense. This feature is not found in dyes and pigments.…”

“…On the other hand, in the ON-state, linearly polarized light emitted from the display is converted into light that is circularly polarized in the opposite direction of the helix of the Ch-LC layer by a quarter wavelength plate (QWP), 5,6 and the light from the display can transmit through the film without loss. 3 In addition, unlike metal decoration films, Ch-LC films transmit radio waves. Therefore, they can be applied for decoration of electronic devices such as smartphones.…”