Patent ID: 10884267

Abstract:
The present invention is notably directed to display device (1, 1a d), comprising a set of pixels, each having a layer structure (2, 2c, 2d) that includes: a bi-stable, phase change material (10), or bi-stable PCM, having at least two reversibly switchable states, in which the PCM exhibits two different values of refractive index and/or optical absorption; and a heating element (17, 17c, 17d), electrically insulated from the PCM (10) and in thermal communication with the PCM (10) in the layer structure (2, 2c, 2d). The display device further comprises a set of nonlinear, monostable resistive switching elements (21), each in electrical communication with the heating element (17, 17c, 17d) of one of the pixels. The resistive switching elements are designed so as to exhibit, each: a low resistance, unstable state, which allows the heating element (17, 17c, 17d) to be energized via the resistive switching element (21), so as to heat the PCM (10) and reversibly change a refractive index and/or an optical absorption thereof, in operation; and a high-resistance, stable state, which allows leakage currents to be mitigated, so as to prevent inadvertent switching of the PCM (10) from one of its states to the other, in operation. The device further comprises a controller (30) configured to energize any of the pixels via a respective one of the resistive switching elements (21), so as to switch the latter from its high-resistance state to its low resistance state, in order to energize a respective heating element (17, 17c, 17d) and, in turn, reversibly change a refractive index and/or an optical absorption of a respective PCM (10). The present invention is further directed to related devices or apparatuses, such as passive matrix addressing displays, and methods of operations.