Figure 5.

Temporal sequence of (a) the luminance output of the Davis Powerbeam VI DLP display showing bright white; (b) the frame sync; and the shutter controller (c) “red” circuit; (d) “blue” circuit; and (e) “green” circuit. The three “color” circuits control the shutters. Negative voltage opens the shutter (high light transmission) for the eye specified for that circuit. For example, the right eye might be driven by the “red” and “green” circuits, therefore opening twice per frame. Meanwhile the “blue” and “green” circuits might drive the left eye. “Green” elements of the image could be seen binocularly (e.g., fusion lock). The temporal-luminance sequence of the Powerbeam VI display is more complex than the schematic in Fig. 4, and actually even more complex at other luminances, as shown in (f) for various values of just the red channel. This is a function of the binary pulse-width modulation technique used to create gray levels⁴¹ and the addition of “white” to enhance perceived brightness and contrast. Measurements were made with the color wheel removed, so the appearance was always grayscale. The time of each segment of the frame sequence was measured empirically and used to establish the shutter control switch settings.