Despite the spatial and temporal non-uniformities associated with the TFT, implementation of stable and uniform backplanes in which the TFTs provide analog functions is described in detail with examples. The development of stable driving schemes for different applications is a critical step toward the realization of reliable and practical imagers and displays. In addition to high stability, the implementation cost, power consumption, and additive noise must be mitigated. To maximize the performance of various applications, different solutions are required since the specifications vary substantially. Thus, a set of driving schemes that can cover a wide range of intended applications for TFT backplanes is recommended.

Although the current mode active matrix has an intrinsic immunity to mismatches and differential aging, the long settling time at low current levels and large parasitic capacitance is a lingering issue, particularly for large-area applications. Consequently, a current-biased voltage-programmed (CBVP) pixel circuit that benefits from the high immunity of current programming yet has a fast settling time, low implementation cost, and low power consumption is proposed. In particular, the CBVP driving scheme is adequate for technologies that are prone to mobility as well as VT variations. A 16 × 12 sensor array is fabricated with a CBVP pixel circuit that demonstrates a low noise. The array uses an operational trans-resistance amplifier (OTRA) as the readout circuitry. This enables a faster readout process and therefore real-time operation. In addition, and unlike the hybrid PPS-APS driving schemes, a gain-boosting technique based on a MIS capacitor is developed that can improve the input dynamic range from extremely low to high input signal intensities.