Abstract
We have studied the off-axis light transmission properties of the bright state in Pi-cell (π-cell) devices as a function of the white state director configuration that is determined by the applied white state voltage and the pretilt angle of the device. Results show that below certain values of the voltage or pretilt angle, the off-axis light transmission properties are insensitive to these parameters and can be described by a previously considered simple model. However, above a critical pretilt angle or white state voltage, the light transmittance is a much stronger function of the incident angle of light. To understand the facts, we develop a model that explains this result and provides a description of the basic issues affecting the optics of these types of devices.