Matrix array display devices with light sensing elements and associated storage capacitors
First Claim
1. A matrix display device comprising on a substrate an array of addressable pixels each having a display element and a display element control circuit for controlling the operation of the display element, wherein the display element control circuit includes a charge storage capacitor and an associated thin film photosensitive semiconductor material having doped contact regions laterally spaced on the substrate and an intervening region, and wherein the storage capacitor comprises a conductive layer extending substantially traversely of the semiconductor strip over one contact region thereof with a layer of dielectric material being disposed between the conductive layer and that contact region;
- wherein a structure of each one pixel of said array of addressable pixels is modified relative to said storage capacitor to be relatively smaller than said storage capacitor so that a portion of said storage capacitor additionally comprises a light shielding means for shielding ambient light to said each one pixel.
1 Assignment
0 Petitions
Accused Products
Abstract
A matrix array display device has an array of pixels on a substrate which each have a display element, such as an electroluminescent display element. An associated control circuit including a storage capacitor and a light sensing element are connected thereto for regulating charge stored on the capacitor and responsive, for example, to light emitted from the display element so as to regulate operation of the display element. The light sensing elements include thin film semiconductor devices each having a strip of semiconductor material with laterally-spaced, doped, contact regions and the associated storage capacitor is formed by a conductive layer extending substantially transversely of the strip over one contact region with intervening dielectric material. A predetermined relationship between the storage capacitor and photosensitive device characteristics is then ensured even though dimensional variations in component layers may occur due to manufacturing tolerances. Alternatively, the conductive layer may be provided at the side of the strip opposite the gate and used also as a shield for ambient light.
-
Citations
12 Claims
-
1. A matrix display device comprising on a substrate an array of addressable pixels each having a display element and a display element control circuit for controlling the operation of the display element, wherein the display element control circuit includes a charge storage capacitor and an associated thin film photosensitive semiconductor material having doped contact regions laterally spaced on the substrate and an intervening region, and wherein the storage capacitor comprises a conductive layer extending substantially traversely of the semiconductor strip over one contact region thereof with a layer of dielectric material being disposed between the conductive layer and that contact region;
wherein a structure of each one pixel of said array of addressable pixels is modified relative to said storage capacitor to be relatively smaller than said storage capacitor so that a portion of said storage capacitor additionally comprises a light shielding means for shielding ambient light to said each one pixel.
- 2. A matrix display device comprising on a substrate an array of addressable pixels each having a display element and a display element control circuit for controlling the operation of the display element, wherein the display element control circuit includes a charge storage capacitor and an associated thin film photosensitive semiconductor material having doped contact regions laterally spaced on the substrate and an intervening region, and wherein the storage capacitor comprises a conductive layer extending substantially traversely of the semiconductor strip over one contact region thereof with a layer of dielectric material being disposed between the conductive layer and that contact region wherein the photosensitive device comprises a gated photosensitive device having a gate extending over the intervening region of the semiconductor strip and separated therefrom by dielectrical material.
Specification